Methods to induce and measure electrical activities at specific sites in the heart to diagnose and treat problems with the heart's electrical system.
The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
An impulse-conducting system composed of modified cardiac muscle, having the power of spontaneous rhythmicity and conduction more highly developed than the rest of the heart.
Regulation of the rate of contraction of the heart muscles by an artificial pacemaker.
Recording of the moment-to-moment electromotive forces of the HEART as projected onto various sites on the body's surface, delineated as a scalar function of time. The recording is monitored by a tracing on slow moving chart paper or by observing it on a cardioscope, which is a CATHODE RAY TUBE DISPLAY.
Any disturbances of the normal rhythmic beating of the heart or MYOCARDIAL CONTRACTION. Cardiac arrhythmias can be classified by the abnormalities in HEART RATE, disorders of electrical impulse generation, or impulse conduction.
A form of ventricular pre-excitation characterized by a short PR interval and a long QRS interval with a delta wave. In this syndrome, atrial impulses are abnormally conducted to the HEART VENTRICLES via an ACCESSORY CONDUCTING PATHWAY that is located between the wall of the right or left atria and the ventricles, also known as a BUNDLE OF KENT. The inherited form can be caused by mutation of PRKAG2 gene encoding a gamma-2 regulatory subunit of AMP-activated protein kinase.
Striated muscle cells found in the heart. They are derived from cardiac myoblasts (MYOBLASTS, CARDIAC).
A generic expression for any tachycardia that originates above the BUNDLE OF HIS.
A group of conditions in which HEART VENTRICLE activation by the atrial impulse is faster than the normal impulse conduction from the SINOATRIAL NODE. In these pre-excitation syndromes, atrial impulses often bypass the ATRIOVENTRICULAR NODE delay and travel via ACCESSORY CONDUCTING PATHWAYS connecting the atrium directly to the BUNDLE OF HIS.
Agents used for the treatment or prevention of cardiac arrhythmias. They may affect the polarization-repolarization phase of the action potential, its excitability or refractoriness, or impulse conduction or membrane responsiveness within cardiac fibers. Anti-arrhythmia agents are often classed into four main groups according to their mechanism of action: sodium channel blockade, beta-adrenergic blockade, repolarization prolongation, or calcium channel blockade.
Abnormally rapid heartbeat, usually with a HEART RATE above 100 beats per minute for adults. Tachycardia accompanied by disturbance in the cardiac depolarization (cardiac arrhythmia) is called tachyarrhythmia.
An abnormally rapid ventricular rhythm usually in excess of 150 beats per minute. It is generated within the ventricle below the BUNDLE OF HIS, either as autonomic impulse formation or reentrant impulse conduction. Depending on the etiology, onset of ventricular tachycardia can be paroxysmal (sudden) or nonparoxysmal, its wide QRS complexes can be uniform or polymorphic, and the ventricular beating may be independent of the atrial beating (AV dissociation).
The hollow, muscular organ that maintains the circulation of the blood.
Unexpected rapid natural death due to cardiovascular collapse within one hour of initial symptoms. It is usually caused by the worsening of existing heart diseases. The sudden onset of symptoms, such as CHEST PAIN and CARDIAC ARRHYTHMIAS, particularly VENTRICULAR TACHYCARDIA, can lead to the loss of consciousness and cardiac arrest followed by biological death. (from Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 7th ed., 2005)
A small nodular mass of specialized muscle fibers located in the interatrial septum near the opening of the coronary sinus. It gives rise to the atrioventricular bundle of the conduction system of the heart.
The chambers of the heart, to which the BLOOD returns from the circulation.
A potentially lethal cardiac arrhythmia that is characterized by uncoordinated extremely rapid firing of electrical impulses (400-600/min) in HEART VENTRICLES. Such asynchronous ventricular quivering or fibrillation prevents any effective cardiac output and results in unconsciousness (SYNCOPE). It is one of the major electrocardiographic patterns seen with CARDIAC ARREST.
Removal of tissue with electrical current delivered via electrodes positioned at the distal end of a catheter. Energy sources are commonly direct current (DC-shock) or alternating current at radiofrequencies (usually 750 kHz). The technique is used most often to ablate the AV junction and/or accessory pathways in order to interrupt AV conduction and produce AV block in the treatment of various tachyarrhythmias.
The volume of BLOOD passing through the HEART per unit of time. It is usually expressed as liters (volume) per minute so as not to be confused with STROKE VOLUME (volume per beat).
Abnormally rapid heartbeats caused by reentry of atrial impulse into the dual (fast and slow) pathways of ATRIOVENTRICULAR NODE. The common type involves a blocked atrial impulse in the slow pathway which reenters the fast pathway in a retrograde direction and simultaneously conducts to the atria and the ventricles leading to rapid HEART RATE of 150-250 beats per minute.
The period of time following the triggering of an ACTION POTENTIAL when the CELL MEMBRANE has changed to an unexcitable state and is gradually restored to the resting (excitable) state. During the absolute refractory period no other stimulus can trigger a response. This is followed by the relative refractory period during which the cell gradually becomes more excitable and the stronger impulse that is required to illicit a response gradually lessens to that required during the resting state.
The lower right and left chambers of the heart. The right ventricle pumps venous BLOOD into the LUNGS and the left ventricle pumps oxygenated blood into the systemic arterial circulation.
The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)
A class Ia antiarrhythmic drug that is structurally-related to PROCAINE.
An antianginal and class III antiarrhythmic drug. It increases the duration of ventricular and atrial muscle action by inhibiting POTASSIUM CHANNELS and VOLTAGE-GATED SODIUM CHANNELS. There is a resulting decrease in heart rate and in vascular resistance.
Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.
Abnormally rapid heartbeats caused by reentry circuit in or around the SINOATRIAL NODE. It is characterized by sudden onset and offset episodes of tachycardia with a HEART RATE of 100-150 beats per minute. The P wave is identical to the sinus P wave but with a longer PR interval.
Method in which prolonged electrocardiographic recordings are made on a portable tape recorder (Holter-type system) or solid-state device ("real-time" system), while the patient undergoes normal daily activities. It is useful in the diagnosis and management of intermittent cardiac arrhythmias and transient myocardial ischemia.
Diagnosis of disease states by recording the spontaneous electrical activity of tissues or organs or by the response to stimulation of electrically excitable tissue.
A transient loss of consciousness and postural tone caused by diminished blood flow to the brain (i.e., BRAIN ISCHEMIA). Presyncope refers to the sensation of lightheadedness and loss of strength that precedes a syncopal event or accompanies an incomplete syncope. (From Adams et al., Principles of Neurology, 6th ed, pp367-9)
Abnormal cardiac rhythm that is characterized by rapid, uncoordinated firing of electrical impulses in the upper chambers of the heart (HEART ATRIA). In such case, blood cannot be effectively pumped into the lower chambers of the heart (HEART VENTRICLES). It is caused by abnormal impulse generation.
Surgery performed on the heart.
The abrupt cessation of all vital bodily functions, manifested by the permanent loss of total cerebral, respiratory, and cardiovascular functions.
Recording the locations and measurements of electrical activity in the EPICARDIUM by placing electrodes on the surface of the heart to analyze the patterns of activation and to locate arrhythmogenic sites.
Procedures in which placement of CARDIAC CATHETERS is performed for therapeutic or diagnostic procedures.
The hemodynamic and electrophysiological action of the HEART ATRIA.
Abnormally rapid heartbeats with sudden onset and cessation.
Cessation of heart beat or MYOCARDIAL CONTRACTION. If it is treated within a few minutes, heart arrest can be reversed in most cases to normal cardiac rhythm and effective circulation.
Abnormally rapid heartbeats originating from one or more automatic foci (nonsinus pacemakers) in the HEART ATRIUM but away from the SINOATRIAL NODE. Unlike the reentry mechanism, automatic tachycardia speeds up and slows down gradually. The episode is characterized by a HEART RATE between 135 to less than 200 beats per minute and lasting 30 seconds or longer.
The study of the electrical activity and characteristics of the HEART; MYOCARDIUM; and CARDIOMYOCYTES.
Recording of regional electrophysiological information by analysis of surface potentials to give a complete picture of the effects of the currents from the heart on the body surface. It has been applied to the diagnosis of old inferior myocardial infarction, localization of the bypass pathway in Wolff-Parkinson-White syndrome, recognition of ventricular hypertrophy, estimation of the size of a myocardial infarct, and the effects of different interventions designed to reduce infarct size. The limiting factor at present is the complexity of the recording and analysis, which requires 100 or more electrodes, sophisticated instrumentation, and dedicated personnel. (Braunwald, Heart Disease, 4th ed)
The small mass of modified cardiac muscle fibers located at the junction of the superior vena cava (VENA CAVA, SUPERIOR) and right atrium. Contraction impulses probably start in this node, spread over the atrium (HEART ATRIUM) and are then transmitted by the atrioventricular bundle (BUNDLE OF HIS) to the ventricle (HEART VENTRICLE).
The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.
Elements of limited time intervals, contributing to particular results or situations.
Pathological conditions involving the HEART including its structural and functional abnormalities.
Contractile activity of the MYOCARDIUM.
Small band of specialized CARDIAC MUSCLE fibers that originates in the ATRIOVENTRICULAR NODE and extends into the membranous part of the interventricular septum. The bundle of His, consisting of the left and the right bundle branches, conducts the electrical impulses to the HEART VENTRICLES in generation of MYOCARDIAL CONTRACTION.
Modified cardiac muscle fibers composing the terminal portion of the heart conduction system.
Diseases of multiple peripheral nerves simultaneously. Polyneuropathies usually are characterized by symmetrical, bilateral distal motor and sensory impairment with a graded increase in severity distally. The pathological processes affecting peripheral nerves include degeneration of the axon, myelin or both. The various forms of polyneuropathy are categorized by the type of nerve affected (e.g., sensory, motor, or autonomic), by the distribution of nerve injury (e.g., distal vs. proximal), by nerve component primarily affected (e.g., demyelinating vs. axonal), by etiology, or by pattern of inheritance.
The number of times the HEART VENTRICLES contract per unit of time, usually per minute.
An adrenergic beta-antagonist that is used in the treatment of life-threatening arrhythmias.
Studies in which individuals or populations are followed to assess the outcome of exposures, procedures, or effects of a characteristic, e.g., occurrence of disease.
The propagation of the NERVE IMPULSE along the nerve away from the site of an excitation stimulus.
Implantable devices which continuously monitor the electrical activity of the heart and automatically detect and terminate ventricular tachycardia (TACHYCARDIA, VENTRICULAR) and VENTRICULAR FIBRILLATION. They consist of an impulse generator, batteries, and electrodes.
Impaired conduction of cardiac impulse that can occur anywhere along the conduction pathway, such as between the SINOATRIAL NODE and the right atrium (SA block) or between atria and ventricles (AV block). Heart blocks can be classified by the duration, frequency, or completeness of conduction block. Reversibility depends on the degree of structural or functional defects.
A group of cardiac arrhythmias in which the cardiac contractions are not initiated at the SINOATRIAL NODE. They include both atrial and ventricular premature beats, and are also known as extra or ectopic heartbeats. Their frequency is increased in heart diseases.
An electrical current applied to the HEART to terminate a disturbance of its rhythm, ARRHYTHMIAS, CARDIAC. (Stedman, 25th ed)
A heterogeneous condition in which the heart is unable to pump out sufficient blood to meet the metabolic need of the body. Heart failure can be caused by structural defects, functional abnormalities (VENTRICULAR DYSFUNCTION), or a sudden overload beyond its capacity. Chronic heart failure is more common than acute heart failure which results from sudden insult to cardiac function, such as MYOCARDIAL INFARCTION.
A group of diseases in which the dominant feature is the involvement of the CARDIAC MUSCLE itself. Cardiomyopathies are classified according to their predominant pathophysiological features (DILATED CARDIOMYOPATHY; HYPERTROPHIC CARDIOMYOPATHY; RESTRICTIVE CARDIOMYOPATHY) or their etiological/pathological factors (CARDIOMYOPATHY, ALCOHOLIC; ENDOCARDIAL FIBROELASTOSIS).
A form of heart block in which the electrical stimulation of HEART VENTRICLES is interrupted at either one of the branches of BUNDLE OF HIS thus preventing the simultaneous depolarization of the two ventricles.
An optical isomer of quinine, extracted from the bark of the CHINCHONA tree and similar plant species. This alkaloid dampens the excitability of cardiac and skeletal muscles by blocking sodium and potassium currents across cellular membranes. It prolongs cellular ACTION POTENTIALS, and decreases automaticity. Quinidine also blocks muscarinic and alpha-adrenergic neurotransmission.
Rapid, irregular atrial contractions caused by a block of electrical impulse conduction in the right atrium and a reentrant wave front traveling up the inter-atrial septum and down the right atrial free wall or vice versa. Unlike ATRIAL FIBRILLATION which is caused by abnormal impulse generation, typical atrial flutter is caused by abnormal impulse conduction. As in atrial fibrillation, patients with atrial flutter cannot effectively pump blood into the lower chambers of the heart (HEART VENTRICLES).
An autosomal dominant defect of cardiac conduction that is characterized by an abnormal ST-segment in leads V1-V3 on the ELECTROCARDIOGRAM resembling a right BUNDLE-BRANCH BLOCK; high risk of VENTRICULAR TACHYCARDIA; or VENTRICULAR FIBRILLATION; SYNCOPAL EPISODE; and possible sudden death. This syndrome is linked to mutations of gene encoding the cardiac SODIUM CHANNEL alpha subunit.
A condition in which HEART VENTRICLES exhibit impaired function.
Disease involving the ULNAR NERVE from its origin in the BRACHIAL PLEXUS to its termination in the hand. Clinical manifestations may include PARESIS or PARALYSIS of wrist flexion, finger flexion, thumb adduction, finger abduction, and finger adduction. Sensation over the medial palm, fifth finger, and ulnar aspect of the ring finger may also be impaired. Common sites of injury include the AXILLA, cubital tunnel at the ELBOW, and Guyon's canal at the wrist. (From Joynt, Clinical Neurology, 1995, Ch51 pp43-5)
Enlargement of the HEART, usually indicated by a cardiothoracic ratio above 0.50. Heart enlargement may involve the right, the left, or both HEART VENTRICLES or HEART ATRIA. Cardiomegaly is a nonspecific symptom seen in patients with chronic systolic heart failure (HEART FAILURE) or several forms of CARDIOMYOPATHIES.
Compression of the heart by accumulated fluid (PERICARDIAL EFFUSION) or blood (HEMOPERICARDIUM) in the PERICARDIUM surrounding the heart. The affected cardiac functions and CARDIAC OUTPUT can range from minimal to total hemodynamic collapse.
Procedures using an electrically heated wire or scalpel to treat hemorrhage (e.g., bleeding ulcers) and to ablate tumors, mucosal lesions, and refractory arrhythmias. It is different from ELECTROSURGERY which is used more for cutting tissue than destroying and in which the patient is part of the electric circuit.
An extremely stable inhalation anesthetic that allows rapid adjustments of anesthesia depth with little change in pulse or respiratory rate.
The innermost layer of the heart, comprised of endothelial cells.
Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.
The continuous measurement of physiological processes, blood pressure, heart rate, renal output, reflexes, respiration, etc., in a patient or experimental animal; includes pharmacologic monitoring, the measurement of administered drugs or their metabolites in the blood, tissues, or urine.
The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.
A conical fibro-serous sac surrounding the HEART and the roots of the great vessels (AORTA; VENAE CAVAE; PULMONARY ARTERY). Pericardium consists of two sacs: the outer fibrous pericardium and the inner serous pericardium. The latter consists of an outer parietal layer facing the fibrous pericardium, and an inner visceral layer (epicardium) resting next to the heart, and a pericardial cavity between these two layers.
NECROSIS of the MYOCARDIUM caused by an obstruction of the blood supply to the heart (CORONARY CIRCULATION).
A widely used local anesthetic agent.
A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.
Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues. The standard approach is transthoracic.
A nonflammable, halogenated, hydrocarbon anesthetic that provides relatively rapid induction with little or no excitement. Analgesia may not be adequate. NITROUS OXIDE is often given concomitantly. Because halothane may not produce sufficient muscle relaxation, supplemental neuromuscular blocking agents may be required. (From AMA Drug Evaluations Annual, 1994, p178)
A local anesthetic and cardiac depressant used as an antiarrhythmia agent. Its actions are more intense and its effects more prolonged than those of PROCAINE but its duration of action is shorter than that of BUPIVACAINE or PRILOCAINE.
The amount of BLOOD pumped out of the HEART per beat, not to be confused with cardiac output (volume/time). It is calculated as the difference between the end-diastolic volume and the end-systolic volume.
The veins that return the oxygenated blood from the lungs to the left atrium of the heart.
The hemodynamic and electrophysiological action of the HEART VENTRICLES.
Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.
Recording of electric potentials in the retina after stimulation by light.
The return of a sign, symptom, or disease after a remission.
Observation of a population for a sufficient number of persons over a sufficient number of years to generate incidence or mortality rates subsequent to the selection of the study group.
A device designed to stimulate, by electric impulses, contraction of the heart muscles. It may be temporary (external) or permanent (internal or internal-external).
A voltage-gated sodium channel subtype that mediates the sodium ion PERMEABILITY of CARDIOMYOCYTES. Defects in the SCN5A gene, which codes for the alpha subunit of this sodium channel, are associated with a variety of CARDIAC DISEASES that result from loss of sodium channel function.
Conical muscular projections from the walls of the cardiac ventricles, attached to the cusps of the atrioventricular valves by the chordae tendineae.
Irregular HEART RATE caused by abnormal function of the SINOATRIAL NODE. It is characterized by a greater than 10% change between the maximum and the minimum sinus cycle length or 120 milliseconds.
A colorless to white crystalline compound with a camphoraceous odor and taste. It is a widely used preservative in various pharmaceutical solutions, especially injectables. Also, it is an active ingredient in certain oral sedatives and topical anesthetics.
Ion channels that specifically allow the passage of SODIUM ions. A variety of specific sodium channel subtypes are involved in serving specialized functions such as neuronal signaling, CARDIAC MUSCLE contraction, and KIDNEY function.
In screening and diagnostic tests, the probability that a person with a positive test is a true positive (i.e., has the disease), is referred to as the predictive value of a positive test; whereas, the predictive value of a negative test is the probability that the person with a negative test does not have the disease. Predictive value is related to the sensitivity and specificity of the test.
Theoretical representations that simulate the behavior or activity of the cardiovascular system, processes, or phenomena; includes the use of mathematical equations, computers and other electronic equipment.
A stable, non-explosive inhalation anesthetic, relatively free from significant side effects.
A disorder of cardiac function caused by insufficient blood flow to the muscle tissue of the heart. The decreased blood flow may be due to narrowing of the coronary arteries (CORONARY ARTERY DISEASE), to obstruction by a thrombus (CORONARY THROMBOSIS), or less commonly, to diffuse narrowing of arterioles and other small vessels within the heart. Severe interruption of the blood supply to the myocardial tissue may result in necrosis of cardiac muscle (MYOCARDIAL INFARCTION).
A condition in which the LEFT VENTRICLE of the heart was functionally impaired. This condition usually leads to HEART FAILURE; MYOCARDIAL INFARCTION; and other cardiovascular complications. Diagnosis is made by measuring the diminished ejection fraction and a depressed level of motility of the left ventricular wall.
Isopropyl analog of EPINEPHRINE; beta-sympathomimetic that acts on the heart, bronchi, skeletal muscle, alimentary tract, etc. It is used mainly as bronchodilator and heart stimulant.
Recording of electric currents developed in the brain by means of electrodes applied to the scalp, to the surface of the brain, or placed within the substance of the brain.
A class I anti-arrhythmic agent (one that interferes directly with the depolarization of the cardiac membrane and thus serves as a membrane-stabilizing agent) with a depressant action on the heart similar to that of guanidine. It also possesses some anticholinergic and local anesthetic properties.
The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).
The electrical properties, characteristics of living organisms, and the processes of organisms or their parts that are involved in generating and responding to electrical charges.
Use of electric potential or currents to elicit biological responses.
Precursor cells destined to differentiate into cardiac myocytes (MYOCYTES, CARDIAC).
Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.
Diseases characterized by MYOTONIA, which may be inherited or acquired. Myotonia may be restricted to certain muscles (e.g., intrinsic hand muscles) or occur as a generalized condition.
Entrapment of the MEDIAN NERVE in the carpal tunnel, which is formed by the flexor retinaculum and the CARPAL BONES. This syndrome may be associated with repetitive occupational trauma (CUMULATIVE TRAUMA DISORDERS); wrist injuries; AMYLOID NEUROPATHIES; rheumatoid arthritis (see ARTHRITIS, RHEUMATOID); ACROMEGALY; PREGNANCY; and other conditions. Symptoms include burning pain and paresthesias involving the ventral surface of the hand and fingers which may radiate proximally. Impairment of sensation in the distribution of the median nerve and thenar muscle atrophy may occur. (Joynt, Clinical Neurology, 1995, Ch51, p45)
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
Cardiac arrhythmias that are characterized by excessively slow HEART RATE, usually below 50 beats per minute in human adults. They can be classified broadly into SINOATRIAL NODE dysfunction and ATRIOVENTRICULAR BLOCK.
A potent anti-arrhythmia agent, effective in a wide range of ventricular and atrial ARRHYTHMIAS and TACHYCARDIAS.
Myosin type II isoforms found in cardiac muscle.
Visualization of the heart structure and cardiac blood flow for diagnostic evaluation or to guide cardiac procedures via techniques including ENDOSCOPY (cardiac endoscopy, sometimes refered to as cardioscopy), RADIONUCLIDE IMAGING; MAGNETIC RESONANCE IMAGING; TOMOGRAPHY; or ULTRASONOGRAPHY.
This structure includes the thin muscular atrial septum between the two HEART ATRIA, and the thick muscular ventricular septum between the two HEART VENTRICLES.
Gases or volatile liquids that vary in the rate at which they induce anesthesia; potency; the degree of circulation, respiratory, or neuromuscular depression they produce; and analgesic effects. Inhalation anesthetics have advantages over intravenous agents in that the depth of anesthesia can be changed rapidly by altering the inhaled concentration. Because of their rapid elimination, any postoperative respiratory depression is of relatively short duration. (From AMA Drug Evaluations Annual, 1994, p173)
Cyclopentanophenanthrenes with a 5- or 6-membered lactone ring attached at the 17-position and SUGARS attached at the 3-position. Plants they come from have long been used in congestive heart failure. They increase the force of cardiac contraction without significantly affecting other parameters, but are very toxic at larger doses. Their mechanism of action usually involves inhibition of the NA(+)-K(+)-EXCHANGING ATPASE and they are often used in cell biological studies for that purpose.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
Antiarrhythmic agent pharmacologically similar to LIDOCAINE. It may have some anticonvulsant properties.
The use of freezing as a special surgical technique to destroy or excise tissue.
The relationship between the dose of an administered drug and the response of the organism to the drug.
Cell membrane glycoproteins that are selectively permeable to potassium ions. At least eight major groups of K channels exist and they are made up of dozens of different subunits.
An antiarrhythmia agent that is particularly effective in ventricular arrhythmias. It also has weak beta-blocking activity.
Mechanical compression of nerves or nerve roots from internal or external causes. These may result in a conduction block to nerve impulses (due to MYELIN SHEATH dysfunction) or axonal loss. The nerve and nerve sheath injuries may be caused by ISCHEMIA; INFLAMMATION; or a direct mechanical effect.
The electric response evoked in the CEREBRAL CORTEX by stimulation along AFFERENT PATHWAYS from PERIPHERAL NERVES to CEREBRUM.
A state of subnormal or depressed cardiac output at rest or during stress. It is a characteristic of CARDIOVASCULAR DISEASES, including congenital, valvular, rheumatic, hypertensive, coronary, and cardiomyopathic. The serious form of low cardiac output is characterized by marked reduction in STROKE VOLUME, and systemic vasoconstriction resulting in cold, pale, and sometimes cyanotic extremities.
A calcium channel blocker that is a class IV anti-arrhythmia agent.
A condition that is characterized by episodes of fainting (SYNCOPE) and varying degree of ventricular arrhythmia as indicated by the prolonged QT interval. The inherited forms are caused by mutation of genes encoding cardiac ion channel proteins. The two major forms are ROMANO-WARD SYNDROME and JERVELL-LANGE NIELSEN SYNDROME.
Pathologic processes that affect patients after a surgical procedure. They may or may not be related to the disease for which the surgery was done, and they may or may not be direct results of the surgery.
A type of cardiac arrhythmia with premature contractions of the HEART VENTRICLES. It is characterized by the premature QRS complex on ECG that is of abnormal shape and great duration (generally >129 msec). It is the most common form of all cardiac arrhythmias. Premature ventricular complexes have no clinical significance except in concurrence with heart diseases.
Occurrence of heart arrest in an individual when there is no immediate access to medical personnel or equipment.
Computer-assisted processing of electric, ultrasonic, or electronic signals to interpret function and activity.
An electrophysiologic technique for studying cells, cell membranes, and occasionally isolated organelles. All patch-clamp methods rely on a very high-resistance seal between a micropipette and a membrane; the seal is usually attained by gentle suction. The four most common variants include on-cell patch, inside-out patch, outside-out patch, and whole-cell clamp. Patch-clamp methods are commonly used to voltage clamp, that is control the voltage across the membrane and measure current flow, but current-clamp methods, in which the current is controlled and the voltage is measured, are also used.
A major nerve of the upper extremity. In humans, the fibers of the median nerve originate in the lower cervical and upper thoracic spinal cord (usually C6 to T1), travel via the brachial plexus, and supply sensory and motor innervation to parts of the forearm and hand.
The volume of the HEART, usually relating to the volume of BLOOD contained within it at various periods of the cardiac cycle. The amount of blood ejected from a ventricle at each beat is STROKE VOLUME.
The geometric and structural changes that the HEART VENTRICLES undergo, usually following MYOCARDIAL INFARCTION. It comprises expansion of the infarct and dilatation of the healthy ventricle segments. While most prevalent in the left ventricle, it can also occur in the right ventricle.
The transference of a heart from one human or animal to another.
The application of probability and statistical methods to calculate the risk of occurrence of any event, such as onset of illness, recurrent disease, hospitalization, disability, or death. It may include calculation of the anticipated money costs of such events and of the premiums necessary to provide for payment of such costs.
An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.
A condition caused by dysfunctions related to the SINOATRIAL NODE including impulse generation (CARDIAC SINUS ARREST) and impulse conduction (SINOATRIAL EXIT BLOCK). It is characterized by persistent BRADYCARDIA, chronic ATRIAL FIBRILLATION, and failure to resume sinus rhythm following CARDIOVERSION. This syndrome can be congenital or acquired, particularly after surgical correction for heart defects.
A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.
A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.
One of the three polypeptide chains that make up the TROPONIN complex. It inhibits F-actin-myosin interactions.
A state characterized by loss of feeling or sensation. This depression of nerve function is usually the result of pharmacologic action and is induced to allow performance of surgery or other painful procedures.
The ENTERIC NERVOUS SYSTEM; PARASYMPATHETIC NERVOUS SYSTEM; and SYMPATHETIC NERVOUS SYSTEM taken together. Generally speaking, the autonomic nervous system regulates the internal environment during both peaceful activity and physical or emotional stress. Autonomic activity is controlled and integrated by the CENTRAL NERVOUS SYSTEM, especially the HYPOTHALAMUS and the SOLITARY NUCLEUS, which receive information relayed from VISCERAL AFFERENTS.
Drugs that block nerve conduction when applied locally to nerve tissue in appropriate concentrations. They act on any part of the nervous system and on every type of nerve fiber. In contact with a nerve trunk, these anesthetics can cause both sensory and motor paralysis in the innervated area. Their action is completely reversible. (From Gilman AG, et. al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed) Nearly all local anesthetics act by reducing the tendency of voltage-dependent sodium channels to activate.
An imbalance between myocardial functional requirements and the capacity of the CORONARY VESSELS to supply sufficient blood flow. It is a form of MYOCARDIAL ISCHEMIA (insufficient blood supply to the heart muscle) caused by a decreased capacity of the coronary vessels.
The hemodynamic and electrophysiological action of the left HEART VENTRICLE. Its measurement is an important aspect of the clinical evaluation of patients with heart disease to determine the effects of the disease on cardiac performance.
A prediction of the probable outcome of a disease based on a individual's condition and the usual course of the disease as seen in similar situations.
A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.
Electrical responses recorded from nerve, muscle, SENSORY RECEPTOR, or area of the CENTRAL NERVOUS SYSTEM following stimulation. They range from less than a microvolt to several microvolts. The evoked potential can be auditory (EVOKED POTENTIALS, AUDITORY), somatosensory (EVOKED POTENTIALS, SOMATOSENSORY), visual (EVOKED POTENTIALS, VISUAL), or motor (EVOKED POTENTIALS, MOTOR), or other modalities that have been reported.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
A class of drugs that act by inhibition of sodium influx through cell membranes. Blockade of sodium channels slows the rate and amplitude of initial rapid depolarization, reduces cell excitability, and reduces conduction velocity.
Surgically placed electric conductors through which ELECTRIC STIMULATION is delivered to or electrical activity is recorded from a specific point inside the body.
A characteristic symptom complex.
Diseases of the peripheral nerves external to the brain and spinal cord, which includes diseases of the nerve roots, ganglia, plexi, autonomic nerves, sensory nerves, and motor nerves.
Developmental abnormalities involving structures of the heart. These defects are present at birth but may be discovered later in life.
A nucleoside that is composed of ADENINE and D-RIBOSE. Adenosine or adenosine derivatives play many important biological roles in addition to being components of DNA and RNA. Adenosine itself is a neurotransmitter.
Controlled physical activity which is performed in order to allow assessment of physiological functions, particularly cardiovascular and pulmonary, but also aerobic capacity. Maximal (most intense) exercise is usually required but submaximal exercise is also used.
Recording of the changes in electric potential of muscle by means of surface or needle electrodes.
Drugs that bind to but do not activate beta-adrenergic receptors thereby blocking the actions of beta-adrenergic agonists. Adrenergic beta-antagonists are used for treatment of hypertension, cardiac arrhythmias, angina pectoris, glaucoma, migraine headaches, and anxiety.
The restoration of the sequential order of contraction and relaxation of the HEART ATRIA and HEART VENTRICLES by atrio-biventricular pacing.
Electrodes with an extremely small tip, used in a voltage clamp or other apparatus to stimulate or record bioelectric potentials of single cells intracellularly or extracellularly. (Dorland, 28th ed)
Examinations used to diagnose and treat heart conditions.
One of the three polypeptide chains that make up the TROPONIN complex. It is a cardiac-specific protein that binds to TROPOMYOSIN. It is released from damaged or injured heart muscle cells (MYOCYTES, CARDIAC). Defects in the gene encoding troponin T result in FAMILIAL HYPERTROPHIC CARDIOMYOPATHY.
An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
The artificial substitution of heart and lung action as indicated for HEART ARREST resulting from electric shock, DROWNING, respiratory arrest, or other causes. The two major components of cardiopulmonary resuscitation are artificial ventilation (RESPIRATION, ARTIFICIAL) and closed-chest CARDIAC MASSAGE.
Tumors in any part of the heart. They include primary cardiac tumors and metastatic tumors to the heart. Their interference with normal cardiac functions can cause a wide variety of symptoms including HEART FAILURE; CARDIAC ARRHYTHMIAS; or EMBOLISM.
Institutions specializing in the care of patients with heart disorders.
Voltage-dependent cell membrane glycoproteins selectively permeable to calcium ions. They are categorized as L-, T-, N-, P-, Q-, and R-types based on the activation and inactivation kinetics, ion specificity, and sensitivity to drugs and toxins. The L- and T-types are present throughout the cardiovascular and central nervous systems and the N-, P-, Q-, & R-types are located in neuronal tissue.
A group of compounds that contain the general formula R-OCH3.
The decrease in a measurable parameter of a PHYSIOLOGICAL PROCESS, including cellular, microbial, and plant; immunological, cardiovascular, respiratory, reproductive, urinary, digestive, neural, musculoskeletal, ocular, and skin physiological processes; or METABOLIC PROCESS, including enzymatic and other pharmacological processes, by a drug or other chemical.
The qualitative or quantitative estimation of the likelihood of adverse effects that may result from exposure to specified health hazards or from the absence of beneficial influences. (Last, Dictionary of Epidemiology, 1988)
Artificial substitutes for body parts, and materials inserted into tissue for functional, cosmetic, or therapeutic purposes. Prostheses can be functional, as in the case of artificial arms and legs, or cosmetic, as in the case of an artificial eye. Implants, all surgically inserted or grafted into the body, tend to be used therapeutically. IMPLANTS, EXPERIMENTAL is available for those used experimentally.
A form of CARDIAC MUSCLE disease that is characterized by ventricular dilation, VENTRICULAR DYSFUNCTION, and HEART FAILURE. Risk factors include SMOKING; ALCOHOL DRINKING; HYPERTENSION; INFECTION; PREGNANCY; and mutations in the LMNA gene encoding LAMIN TYPE A, a NUCLEAR LAMINA protein.
Agents that have a strengthening effect on the heart or that can increase cardiac output. They may be CARDIAC GLYCOSIDES; SYMPATHOMIMETICS; or other drugs. They are used after MYOCARDIAL INFARCT; CARDIAC SURGICAL PROCEDURES; in SHOCK; or in congestive heart failure (HEART FAILURE).
Electrical waves in the CEREBRAL CORTEX generated by BRAIN STEM structures in response to auditory click stimuli. These are found to be abnormal in many patients with CEREBELLOPONTINE ANGLE lesions, MULTIPLE SCLEROSIS, or other DEMYELINATING DISEASES.
Adjustment of the eyes under conditions of low light. The sensitivity of the eye to light is increased during dark adaptation.
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
The action of a drug that may affect the activity, metabolism, or toxicity of another drug.
Peripheral, autonomic, and cranial nerve disorders that are associated with DIABETES MELLITUS. These conditions usually result from diabetic microvascular injury involving small blood vessels that supply nerves (VASA NERVORUM). Relatively common conditions which may be associated with diabetic neuropathy include third nerve palsy (see OCULOMOTOR NERVE DISEASES); MONONEUROPATHY; mononeuropathy multiplex; diabetic amyotrophy; a painful POLYNEUROPATHY; autonomic neuropathy; and thoracoabdominal neuropathy. (From Adams et al., Principles of Neurology, 6th ed, p1325)
The long-term (minutes to hours) administration of a fluid into the vein through venipuncture, either by letting the fluid flow by gravity or by pumping it.
Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.
Ultrashort-acting anesthetics that are used for induction. Loss of consciousness is rapid and induction is pleasant, but there is no muscle relaxation and reflexes frequently are not reduced adequately. Repeated administration results in accumulation and prolongs the recovery time. Since these agents have little if any analgesic activity, they are seldom used alone except in brief minor procedures. (From AMA Drug Evaluations Annual, 1994, p174)
Any pathological condition where fibrous connective tissue invades any organ, usually as a consequence of inflammation or other injury.
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
The heart of the fetus of any viviparous animal. It refers to the heart in the postembryonic period and is differentiated from the embryonic heart (HEART/embryology) only on the basis of time.
The record of descent or ancestry, particularly of a particular condition or trait, indicating individual family members, their relationships, and their status with respect to the trait or condition.
A class of drugs that act by selective inhibition of calcium influx through cellular membranes.
Levels within a diagnostic group which are established by various measurement criteria applied to the seriousness of a patient's disorder.
The electric response evoked in the CEREBRAL CORTEX by ACOUSTIC STIMULATION or stimulation of the AUDITORY PATHWAYS.
The time from the onset of a stimulus until a response is observed.
Electric conductors through which electric currents enter or leave a medium, whether it be an electrolytic solution, solid, molten mass, gas, or vacuum.
Slender processes of NEURONS, including the AXONS and their glial envelopes (MYELIN SHEATH). Nerve fibers conduct nerve impulses to and from the CENTRAL NERVOUS SYSTEM.
General or unspecified injuries to the heart.
Diseases which have one or more of the following characteristics: they are permanent, leave residual disability, are caused by nonreversible pathological alteration, require special training of the patient for rehabilitation, or may be expected to require a long period of supervision, observation, or care. (Dictionary of Health Services Management, 2d ed)
The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.
Diversion of the flow of blood from the entrance of the right atrium directly to the aorta (or femoral artery) via an oxygenator thus bypassing both the heart and lungs.

First human experience with pulmonary vein isolation using a through-the-balloon circumferential ultrasound ablation system for recurrent atrial fibrillation. (1/1050)

BACKGROUND: Standard mapping and ablation of focal sources of atrial fibrillation are associated with very long procedure times and low efficacy. An anatomic approach to complete pulmonary vein isolation could overcome these limitations. METHODS AND RESULTS: Fifteen patients with atrial fibrillation refractory to medication underwent circumferential isolation of the pulmonary veins by using a novel catheter, with an ultrasound transducer (8-MHz) mounted near the tip, in a saline-filled balloon. Twelve atrial foci and/or atrial fibrillation triggers were identified in 9 patients (pulmonary vein locations: left upper, 3; right upper, 6; right middle, 1; right lower, 1; and left inferior, 1). In 5 patients, lesions were placed in the absence of any mapped triggers. Irrespective of trigger mapping, circumferential isolation of both upper pulmonary veins was attempted in all patients. The lower pulmonary veins were ablated when sinus rhythm activation mapping revealed evidence of a sleeve of atrial muscle in the vein. The median number of lesions per patient required to isolate 1 pulmonary vein was 4 (range, 1 to 29). After ablation, no evidence of narrowing was seen with repeat venography or follow-up computed tomography scan. After a mean follow-up of 35+/-6 weeks, 5 patients had recurrence of atrial fibrillation. Three responded to drugs that were previously ineffective, and 2 remained in atrial fibrillation. CONCLUSIONS: This novel ultrasound ablation system can successfully isolate multiple pulmonary veins. At early follow-up, this approach seems to be effective in preventing recurrent atrial fibrillation in a significant number of patients.  (+info)

Radiofrequency ablation of haemodynamically unstable ventricular tachycardia after myocardial infarction. (2/1050)

OBJECTIVE: To determine whether radiofrequency (RF) ablation might have a role in haemodynamically unstable ventricular tachycardia. METHODS: 10 patients with a history of ventricular tachycardia producing haemodynamic collapse in whom drug treatment had failed and device therapy was rejected underwent RF ablation of ventricular tachycardia in sinus rhythm. The arrhythmogenic zone was defined on the basis of abnormal systolic movement, the presence of fragmentation (low amplitude, prolonged multiphasic electrograms), and pace mapping. RF lesions were delivered in power mode in linear fashion within the defined arrhythmogenic zone. RESULTS: Success (no ventricular tachycardia inducible postablation or at retest) was achieved in six patients, possible success (a different ventricular tachycardia inducible at more aggressive stimulation) in three. In one patient, the procedure was abandoned because of poor catheter stability. There were no clinical events during a mean (SD) follow up period of 23 (10) months in any of the nine patients defined as definite or possible successes. CONCLUSIONS: RF ablation for addressing haemodynamically unstable ventricular tachycardia opens the door for the wider use of catheter ablation for treating this arrhythmia.  (+info)

Anisotropic reentry in a perfused 2-dimensional layer of rabbit ventricular myocardium. (3/1050)

BACKGROUND: Anisotropy creates nonuniformity in electrical propagation and may contribute to the occurrence of unidirectional conduction block and reentry. We describe the characteristics of reentrant tachycardia in a 2D layer of anisotropic ventricular myocardium. METHODS AND RESULTS: A Langendorff-perfused epicardial sheet (1.0+/-0.4 mm, n=35) was created by freezing the intramural layers of the rabbit left ventricle. Epicardial activation maps were constructed by use of different high-resolution mapping arrays connected to a mapping system. In 5 experiments, monophasic action potentials were recorded. In the intact left ventricle, no arrhythmias except VF could be induced. After freezing, programmed electrical stimulation or rapid pacing led to the induction of sustained VT (cycle length 130+/-11 ms). VT was caused by reentry around a functional line of block oriented parallel to the epicardial fiber direction. Action potential recordings demonstrated that the central line of block was kept refractory by electrotonic currents generated by the depolarization waves propagating at either side of the line of block. At the pivot points of the line of block, the pronounced curvature of the turning wave and abrupt loading changes created an excitable gap of 30 ms in the reentrant pathway. CONCLUSIONS: In uniform anisotropic myocardium, reentry around a functional Z-shaped line of block may occur. The core of the circuit is kept refractory by electrotonic currents. The pronounced wave-front curvature and abrupt loading changes at the pivot points cause local conduction delay and create a small excitable gap.  (+info)

Reduction of atrial defibrillation threshold with an interatrial septal electrode. (4/1050)

BACKGROUND: The standard lead configuration for internal atrial defibrillation consists of a shock between electrodes in the right atrial appendage (RAA) and coronary sinus (CS). We tested the hypothesis that the atrial defibrillation threshold (ADFT) of this RAA-->CS configuration would be lowered with use of an additional electrode at the atrial septum (SP). METHODS AND RESULTS: Sustained atrial fibrillation was induced in 8 closed-chest sheep with burst pacing and continuous pericardial infusion of acetyl-ss-methylcholine. Defibrillation electrodes were situated in the RAA, CS, pulmonary artery (PA), low right atrium (LRA), and across the SP. ADFTs of RAA-->CS and 4 other lead configurations were determined in random order by use of a multiple-reversal protocol. Biphasic waveforms of 3/1-ms duration were used for all single and sequential shocks. The ADFT delivered energies for the single-shock configurations were 1.27+/-0.67 J for RAA-->CS and 0. 86+/-0.59 J for RAA+CS-->SP; the ADFTs for the sequential-shock configurations were 0.39+/-0.18 J for RAA-->SP/CS-->SP, 1.16+/-0.72 J for CS-->SP/RAA-->SP, and 0.68+/-0.46 J for RAA-->CS/LRA-->PA. Except for CS-->SP/RAA-->SP versus RAA-->CS and RAA-->CS/LRA-->PA versus RAA+CS-->SP, the ADFT delivered energies of all of the configurations were significantly different from each other (P:<0. 05). CONCLUSIONS: The ADFT of the standard RAA-->CS configuration is markedly reduced with an additional electrode at the atrial SP.  (+info)

Postcardioversion atrial electrophysiologic changes induced by oral verapamil in patients with persistent atrial fibrillation. (5/1050)

OBJECTIVES: The aim of our study was to verify the effect of oral administration of verapamil on atrial electrophysiologic characteristics after cardioversion of persistent atrial fibrillation (AF) in humans. BACKGROUND: Discordant findings have been reported regarding the efficacy of verapamil in preventing the electrical remodeling induced by AF. METHODS: We determined the effective refractory periods (ERPs) at five pacing cycle lengths (300 to 700 ms) and in five right atrial sites after internal cardioversion of persistent AF (mean duration 238.1+/-305.9 days) in 19 patients. Nine patients received oral verapamil (240 mg/day) starting four weeks before the electrophysiologic study, whereas the other 10 patients were in pharmacologic washout. RESULTS: The mean ERPs were 202.0+/-22.7 ms in the washout group and 189.3+/-18.5 ms in the verapamil group (p < 0.0001). The degree of adaptation of refractoriness to rate was similar in the two groups (mean slope value in the washout group and verapamil group: 0.07+/-0.03 and 0.08+/-0.05, respectively), showing a normal or nearly normal adaptation to rate in the majority of the paced sites in both groups. The mean ERP was slightly longer in the septum than in the lateral wall and in the roof, both in the washout and verapamil groups. CONCLUSIONS: In patients with persistent AF, long-term administration of verapamil before internal cardioversion resulted in 1) shortening of atrial ERPs; 2) no change in refractoriness dispersion within the right atrium; and 3) no change in atrial ERP adaptation to rate.  (+info)

A comparison of T-wave alternans, signal averaged electrocardiography and programmed ventricular stimulation for arrhythmia risk stratification. (6/1050)

OBJECTIVES: The goal of this study was to compare T-wave alternans (TWA), signal-averaged electrocardiography (SAECG) and programmed ventricular stimulation (EPS) for arrhythmia risk stratification in patients undergoing electrophysiology study. BACKGROUND: Accurate identification of patients at increased risk for sustained ventricular arrhythmias is critical to prevent sudden cardiac death. T-wave alternans is a heart rate dependent measure of repolarization that correlates with arrhythmia vulnerability in animal and human studies. Signal-averaged electrocardiography and EPS are more established tests used for risk stratification. METHODS: This was a prospective, multicenter trial of 313 patients in sinus rhythm who were undergoing electrophysiologic study. T-wave alternans, assessed with bicycle ergometry, and SAECG were measured before EPS. The primary end point was sudden cardiac death, sustained ventricular tachycardia, ventricular fibrillation or appropriate implantable defibrillator (ICD) therapy, and the secondary end point was any of these arrhythmias or all-cause mortality. RESULTS: Kaplan-Meier survival analysis of the primary end point showed that TWA predicted events with a relative risk of 10.9, EPS had a relative risk of 7.1 and SAECG had a relative risk of 4.5. The relative risks for the secondary end point were 13.9, 4.7 and 3.3, respectively (p < 0.05). Multivariate analysis of 11 clinical parameters identified only TWA and EPS as independent predictors of events. In the prespecified subgroup with known or suspected ventricular arrhythmias, TWA predicted primary end points with a relative risk of 6.1 and secondary end points with a relative risk of 8.0. CONCLUSIONS: T-wave alternans is a strong independent predictor of spontaneous ventricular arrhythmias or death. It performed as well as programmed stimulation and better than SAECG in risk stratifying patients for life-threatening arrhythmias.  (+info)

Targeting the slow pathway for atrioventricular nodal reentrant tachycardia: initial results and long-term follow-up in 379 consecutive patients. (7/1050)

OBJECTIVES: This study is designed to examine the immediate and short-term outcomes of patients who have undergone slow pathway ablation/modification for atrioventricular nodal reentrant tachycardia. BACKGROUND: Targeting the slow pathway has emerged as the superior form of treatment for atrioventricular nodal reentrant tachycardia. This technique has been found effective and is associated with a low complication rate. However, little is known of the long-term outcome of patients undergoing this procedure. METHODS: Over a 40-month period the slow pathway was targeted in 379 consecutive patients with proven atrioventricular nodal reentrant tachycardia. The case records of all patients were examined. Accurate follow-up data is available in 96% of patients a mean of 20.6 months after the procedure. RESULTS: The initial success rate was 97%. The incidence of complete heart block was 0.8% and the mean fluoroscopy duration was 27.3 min. The recurrence rate was 6.9%. Age, number of pulses and fluoroscopy time were positively associated with either initial failure or recurrence. A total of 11.3% of patients were still taking antiarrhythmic medication at follow-up. CONCLUSIONS: Targeting the slow pathway is an effective form of treatment for atrioventricular nodal reentrant tachycardia. The technique has a high initial success rate, a low complication rate and a low recurrence rate at long-term follow-up. Slow pathway modification is associated with similar success rates and recurrence rates as slow pathway ablation and may confer theoretical long-term benefits.  (+info)

Risk of development of delayed atrioventricular block after slow pathway modification in patients with atrioventricular nodal reentrant tachycardia and a pre-existing prolonged PR interval. (8/1050)

AIMS: The objective of this prospective study was to assess risk factors for the development of atrioventricular block following slow pathway modification in patients with atrioventricular nodal reentrant tachycardia and a pre-existing prolonged PR interval. METHODS AND RESULTS: Of 346 consecutive patients with atrioventricular nodal reentrant tachycardia undergoing slow pathway modification, 18 patients (62 +/- 7 years; five females) were found to have a prolonged PR interval prior to ablation. Total elimination of the functional slow pathway was assumed if the antegrade effective refractory period following slow pathway modification was longer than the cycle length of atrioventricular nodal reentrant tachycardia. To detect atrioventricular node conduction disturbances, 24-h Holter recordings were performed 1 day prior to slow pathway modification, and 1 day, 1 week, 1, 3 and 6 months after the procedure. Six patients developed late atrioventricular block. The incidence of delayed atrioventricular block following successful slow pathway modification was higher in patients with, compared to patients without, prolonged PR interval at baseline (6/18 vs 0/328, P < .001). In the former group, the antegrade effective refractory period was longer in patients with, compared to those without, a delayed atrioventricular block (492 +/- 150 ms vs 332 +/- 101 ms, P < 0.05). The incidence of delayed atrioventricular block was higher in patients with total elimination of the slow pathway compared to patients without (5/7 vs 1/11, P < 0.01). CONCLUSIONS: Slow pathway modification in patients with atrioventricular nodal reentrant tachycardia and a prolonged PR interval is highly effective. However, there is a significant risk of development of delayed atrioventricular block, particularly when the procedure results in total elimination of the slow pathway.  (+info)

Jackson J. Liang, Yasuhiro Shirai, David F. Briceño, Daniele Muser, Andres Enriquez, Aung Lin, Matthew C. Hyman, Ramanan Kumareswaran, Jeffrey S. Arkles, Pasquale Santangeli, Robert D. Schaller, Gregory E. Supple, David S. Frankel, Rajat Deo, Andrew E. Epstein, Fermin C. Garcia, Michael P. Riley, Saman Nazarian, David Lin, David J. Callans, Francis E. Marchlinski and Sanjay Dixit ...
Fingerprint Dive into the research topics of Sodium channels from human brain RNA expressed in Xenopus oocyte. Basic electrophysiologic characteristics and their modification by diphenylhydantoin. Together they form a unique fingerprint. ...
BACKGROUND: The significance of atrial fibrillation or tachycardia (AF) induction remains debatable. Some believe that the presence of heart disease (HD) increases the sensitivity and decreases the specificity of programmed atrial stimulation (PAS).
Hindricks G, Weiner S, McElderry T, Jaïs P, Maddox W, Garcia-Bolao JI, Yong Ji S, Sacher F, Willems S, Mounsey J, Maury P, Bollmann A, Duffy E, Raciti G, Tung R, Wong T. Acute safety, effectiveness, and real-world clinical usage of ultra-high density mapping for ablation of cardiac arrhythmias: results of the TRUE HD study. Europace. 2019 Apr 01; 21(4):655-661 ...
Left ventricular (LV) electrical activation pattern could determine optimal LV lead placement site during cardiac resynchronization therapy (CRT) device implant. We sought to determine the feasibility of using EnSite NavX™ electroanatomic mapping s
INTRODUCTION: Three-dimensional electroanatomic mapping (EAM) is routinely used to mark ablated areas during radiofrequency ablation. We hypothesized that EAM overestimates scar formation in the left atrium and that the difference between intra-procedural EAM ablated area and post-procedural scar area in late gadolinium enhancement magnetic resonance imaging (LGE-MRI) predicts atrial fibrillation (AF) recurrence.. METHODS: Of the 235 patients who underwent initial ablation for AF at our institution between August 2011 and December 2012, we retrospectively identified 70 patients who had an MRI merged with intracardiac ultrasound, three-month LGE-MRI, and five months minimum follow-up. CARTO (Biosense Webster) was used during the ablation to map ablated left atrial surface area. Corview software (Marrek Inc) was used to quantify scar in three-month LGE-MRI. Unpaired t-tests and time-to-event analysis were performed on AF recurrence and no AF recurrence subsets.. RESULTS: Of the 70 patients, ...
Local conduction velocity (LCV) in the low amplitude electrogram area is generally low. The quantitative relationship between LCV and bipolar electrogram amplitude (biEA) in the atria remains unclear. We analyzed the reentry circuit of atrial flutter (AFL) in the right atrium (RA), focusing on LCV and biEA on the circuit.. Methods and Results. Twenty-six patients with RA AFL (10 with typical AFL (Group T), 10 incisional AFL (Group I) and 6 non-incisional AFL (Group NI)) were studied using CARTO XP and 4-mm tip catheter. After identification of the reentrant circuit, atrial points activated faster than the neighboring ones on the circuit were identified by isochronal and propagation maps during AFL. LCV was calculated by dividing the distance between the 2 neighboring points on the circuit by the time difference. A total of 194 points were obtained from 26 AFL circuits (7±2 points/AFL), and there was a highly significant positive correlation between LCV and natural logarithm of the peak-to-peak ...
The purpose of the PREMS study is to evaluate the capability of the periodic IEGM feature (intracardiac electrogram) to provide more extensive remote information about cardiac rhythm, sensing and capture, and thus to detect anomalies that may deserve a clinical action.. PREMS is a non-interventional, prospective, and multicenter study. The primary objective is to assess the added clinical value of periodic IEGMs, based on the rate of patients with a rhythm or sensing/pacing anomaly detected on the first IEGM transmitted by Home Monitoring (HM) and non detectable so obvious on the other parameter set offered for the remote follow-up. ...
St. Jude Medical (NYSE:STJ) said today it fully launched its EnSite Precision cardiac mapping system and associated tools in Europe, expanding from an earlier limited release.. The St. Paul, Minn.-based company touted more than 100 installations of the device across Europe so far, supporting more than 5,000 ablation procedures after a targeted release it expanded in April.. We collaborated with leading electrophysiologists to develop a cardiac mapping system that provides the automation, flexibility and precision needed during todays ablation procedures. We are extremely pleased with how the physicians from these European sites have embraced the system and are excited to expand its availability as we seek more approvals, chief medical officer Dr. Mark Carlson said in a press release.. The Ensite cardiac mapping system is designed for use in ablation procedures to visualize and aid in catheter navigation in the heart, providing detailed anatomical models and maps, St. Jude said. The system is ...
A cardiac rhythm management (CRM) system includes an implantable medical device that senses a wireless electrocardiogram (ECG), which is a signal sensed with implantable electrodes and approximating a surface ECG. In one embodiment, the wireless ECG is sensed as a substitute signal for the intracardiac electrogram when the sensing of the intracardiac electrogram becomes unreliable.
An EPS provides valuable information about cardiac arrhythmias by recording intracardiac electrograms and using programmed stimulation techniques. Although the sequence of study protocols may vary with each institution, an EPS routinely begins with baseline measurement of conduction intervals. Subsequently, clinical arrhythmias are induced either by incremental or decremental pacing and extrastimulus techniques. Nurses must understand the technical and psychosocial aspects of an EPS to ensure adequate care. The primary role of nurses is to maintain a safe environment for the patient in the electrophysiology laboratory (i.e., maintain aseptic techniques and intervene when complications occur). Rapid technological advances and the increasing number of well-educated patients require that nurses be knowledgeable and skilled in providing progressive care, such as developing educational programs and support groups for patients and patients families. ...
An implantable cardiac device, e.g., a pacemaker, defibrillator, cardioverter or biventricular pacing device, that can sense cardiac electrical signals and accurately classify the sensed events. The device provides a template signal and a test signal originated from an electrogram. The device further transforms at least the test signal into a representation of the test signal for example in numerical format where the sample values of the test signal take the form of integers. The device further determines a correlation between the template and test signals, and classifies the sense events based on the correlation. The electrogram may be an intracardiac electrogram (IEGM), atrial electrogram (AEGM), ventricular electrogram (VEGM), surface electrocardiogram (ECG) or subcutaneous electrogram.
Visit for all information on Sanjay Bindra M.D., Cardiac Electrophysiologist | Clinical Cardiac Electrophysiology in Bakersfield, CA, 93311. Profile, Reviews, Appointments, Insurances.
An electrophysiology study is performed to evaluate the electrical activity of the heart. The purpose of the electrical system of the heart is to coordinate the pumping of the four chambers of the heart and to control the heart rate so that the heart speeds up and slows down as the demands of the body change. The SA node starts the electrical signal. The electrical signal then travels through the atria causing them to contract. Then it passes through the AV node the bundle of His, and bundle branches and then out to the muscle fibers of the ventricles. As the impulse spreads, the muscles contract and the ventricles pump. To perform an electrophysiology study, three to five electrically sensitive catheters are placed inside the heart to record electrical activity (see fig. 2 and 3). These recordings locate abnormal tissue that causes irregularities in the heartbeat (arrhythmias).. ...
To the Editor,We have read with great interest the article entitled Electrogram-only guided approach to His bundle pacing with minimal fluoroscopy: A single-center experience by Zanon et al1 in the latest issue of the journal. We would like to thank
En la Unidad de Arritmias del Hospital Ramón y Cajal, dirigida por el Doctor Javier Moreno, disponemos de un equipo multidisciplinar de cardiólogos, pediatras y anestesistas.
At the HivE Lab, we believe in creating a lasting impact through educating the community. We partner with the Dana Foundation and their Brain Awareness Campaign. We organize hands-on activities for children of all ages to get them excited about the brain and neuroscience. ...
A pacemaker sense amplifier circuit exhibiting a very high common mode rejection ratio for detecting intracardiac electrogram signals is disclosed. The circuit includes a sampling capacitor which is differentially charged by the intracardiac signal. The voltage stored on the sampling capacitor is periodically applied to a high input impedance differential voltage amplifier which is referenced to the battery ground. The signal is smoothed and reconstructed by a bandpass filter, and is applied to a comparator to generate a logic level pulse indicative of the occurrence of a cardiac depolarization.
An electrophysiology study is performed by a cardiologist, usually as a day procedure, at Epworth Hospital. It involves guiding a catheter containing electrodes to the heart with the aid of x-ray imaging. The electrodes detect the electrical activity of the heart and help diagnose irregular or abnormal heart rhythms. ...
An electrophysiology study measures the electrical activity of your child's heart. Learn what to expect before, during and after this diagnostic test.
Electrophysiology Study (EPS) clinics in Domis de Semerpontlaan at the best price. Find doctors, specialized in Cardiology and compare prices, costs and reviews.
List of 3 doctors offering Intracardiac Electrophysiology Study (EPS) in Manchester. Check out patient reviews, addresses and book a visit!
in a modern cardiac electrophysiology laboratory Kevin A. Wunderle 1 & Mina K. Chung 2 & Sripriya Rayadurgam 3 & Mark A. Miller 3 & Nancy A. Obuchowski 4 & Bruce D ...
Dublin, Oct. 4, 2013-- Research and Markets has announced the addition of the Global Electrophysiology Laboratory Devices- Market Growth Analysis, 2009-2015 report to their offering. The Global Diagnostic Electrophysiology Catheters market forecasts to reach at US $3.1 billion by 2015 at a CAGR of 10.6% during the analysis period 2009-2015. The North American segment accounts for nearly 35% of the global value while Europe claims approximately 30% of the market.
Cardiac electrophysiology (EP) is a test that studies the electrical system of the heart. It is used to understand the causes of heart rhythm disorders and...
Question - Want help interpreting ECG. Do I need to be concerned with QRS low voltage?. Ask a Doctor about Sinus rhythm, Ask a Cardiologist
This paper discusses the critical stress test and the breakdown voltage at low voltage cable NYFGbY with 3x25 mm size. By knowing the type and function of the use of cable wires can be maximized and used for purposes such as the channels of power, especially power lines underground. The data of test results can be known ability of the cable so as not to exceed the actual ability compared with the value of ID, so that the useful life and the characteristics of the cable can be known. From the test results that have been performed on the cable fails the test voltage SPLN 43-2 / IEC 60502-1 KABELINDO NYFGbY rm 0.6/1.2 kV 3x25 mm2 (SNI) PVC sheathed with 0.6/1.2 kV rated voltage, the highest voltage of 41 kV . That the cable is capable of withstanding voltages greater than the value set by SPLN.. ...
We keep a full range of Old Light Bulbs (Incandescent) including all makes of Low Voltage and Calex part number 402504 at great prices starting at ?1.45
We keep a full range of Old Light Bulbs (Incandescent) including all makes of Low Voltage and First Light (Unassigned) part number 300GES110C at great prices starting at ?9.875
Electrogram (EGM) terms pertain to invasive electrophysiologic recording of cardiac impulse conduction. Expand them at first mention. |
Electrogram (EGM) terms pertain to invasive electrophysiologic recording of cardiac impulse conduction. Expand them at first mention. |
Electro-Acuscope or Myopulse is an electro-therapy unit that heals injured tissue by introducing a low voltage micro-current through it.
不動産担保ローンは無担保のローンに比べ金利が安い - 所有している不動産を担保にして借り入れをする不動産担保ローンは 無担保のローンに比べると 不動産の価値にもよりますが 金利が安く 融資額が大きい 長期の借り入れが可能などのメリットがあります》 融資額の内容は所有している […] ...
TY - JOUR. T1 - Use of advanced mapping systems to guide ablation in complex cases. T2 - Experience with noncontact mapping and electroanatomic mapping systems. AU - Gurevitz, Osnat T.. AU - Glikson, Michael. AU - Asirvatham, Samuel. AU - Kester, Tammy A.. AU - Grice, Suellen K.. AU - Munger, Thomas M.. AU - Rea, Robert F.. AU - Shen, Win Kuang. AU - Jahangir, Arshad. AU - Packer, Douglas L.. AU - Hammill, Stephen C.. AU - Friedman, Paul A.. PY - 2005/4/1. Y1 - 2005/4/1. N2 - Objective: This report describes our experience with noncontact mapping and electroanatomic mapping in complex ablations, which are defined as ablations done after failure of conventional ablation. Material and Methods: Patients were included (N = 68; 49% with structural heart disease) in whom previous ablation failed and in whom a second procedure was done with advanced mapping. Non-contact mapping was used in 17 patients, electroanatomic mapping in 36, and both noncontact and electroanatomic mapping in 15. Arrhythmias ...
The ZERO-AF trial is a prospective, multicenter, single blind, 1:1 randomized study. The trial is designed to demonstrate that the safety and effectiveness of the Blazer® Open-Irrigated Ablation Catheter are non-inferior to the safety and effectiveness of the control catheters, for the treatment drug refractory, recurrent, symptomatic, paroxysmal atrial fibrillation. The control catheters are open-irrigated radiofrequency ablation catheters that are approved in the United States for the treatment of drug refractory recurrent symptomatic paroxysmal atrial fibrillation, when used with compatible three-dimensional electroanatomic mapping systems ...
One of the problems with applying these data clinically might be the extra-invasive procedure (insertion of the non-contact balloon to the left ventricle) and the subsequent time and cost. Theoretically it would be very useful to perform non-contact mapping during the implant procedure in order to identify the area of latest activation not obstructed by conduction block and scar. This would also allow the operator to pass the catheter locator signal produced by the non-contact mapping system through the left ventricular lead and therefore steer it to that site. However, at the present time it is recommended that the patient is heavily anticoagulated while the non-contact balloon is in the left heart which would prevent safe implantation of the CRT system.. Fung and colleagues14 have gone some way to try and overcome this problem by comparing non-contact mapping data to tissue Doppler imaging. They found that latest activation on non-contact and tissue Doppler correlated well. They did not ...
OBJECTIVE: The origin and mechanisms of focal and macro-re-entrant atrial tachycardia occurring after ablation of paroxysmal or persistent atrial fibrillation are difficult to determine and are often the cause of distress for both patients and electrophysiologists. The purpose of this study was to describe a novel practical approach which would be helpful in planning the treatment of atrial tachycardia in patients who had received prior atrial fibrillation ablation. We used an algorithm which aims to facilitate mapping and ablation strategies, using both conventional electrophysiological tools and a three-dimensional electroanatomic approach ...
Cambridge Heart develops and commercializes non-invasive diagnostic tests for cardiac disease, with a focus on identifying those at risk for sudden cardiac arrest (SCA). The Company?s products incorporate proprietary Microvolt T-Wave Alternans measurement technologies including the patented Analytic Spectral Method? and ultrasensitive disposable electrode sensors. Medicare reimburses the Analytic Spectral Method? under its National Coverage Policy. Cambridge Heart, founded in 1990, is based in Tewksbury, MA. The company?s Microvolt T-Wave Alternans? (MTWA) test, developed by Cambridge Heart (OTCBB: CAMH), is based on research originally conducted at the Massachusetts Institute of Technology.,, .. Statements contained in this press release are forward-looking statements for purposes of the safe harbor provisions under The Private Securities Litigation Reform Act of 1995. In some cases, we use words such as ?believes?, ?expects?, ...
Author Response.pdf. Reviewer 2 Report. This paper tests the hypothesis that the Kolmogorov complexity of a single atrial bipolar electrogram recorded during AF within the coronary sinus at the beginning of the catheter ablation may predict AF termination directly after pulmonary vein isolation (PVI). Results show significant differences in Kolmogorov complexity between patients with AF termination directly after PVI compared to patients undergoing additional ablation. Therefore, authors affirm that Kolmogorov complexity of electrograms measured at baseline before PVI can predict self-termination of AF directly after PVI. Overall, I believe that the goal of this study is very interesting and the tools used are appropriate. However, I have several major comments regarding the paper:. Authors talk about complexity measures, however they are different types of measurements and they do not measure complexity. Additional 30 second electrograms recorded 30 prior to AF termination were analyzed as the ...
HearTwave II Microvolt T-Wave Alternans System With Analytic Spectral Method,The HearTwave II system is the Cambridge Heart next generation Microvolt T-Wave Alternans (MTWA) testing platform which simplifies hospital and office-based sudden cardiac death risk stratification. This new system offers expanded versatility as it can be configured to perform MTWA and/or standard,medicine,medical supply,medical supplies,medical product
This is an example of a normal finding on intracardiac electrophysiologic (EP) study. The surface electrocardiogram (ECG) is represented in different colors, with its corresponding intervals (ie, PR, QT) on top. A catheter with several electrodes is placed inside the heart, close to the superior vena cava-right atrial junction. This catheter records the sinoatrial node (SN) activity and is depicted here as the high-right atrial (HRA) deflection. Beneath the HRA intracardiac electrogram is the His-bundle intracardiac electrogram, which is recorded by the electrodes of a second catheter placed across the posterior aspect of the tricuspid valve. The His-bundle electrogram provides the most information about atrioventricular (AV) conduction. Three main deflections are present, with 2 intervals: (1) the A deflection corresponds to the activation of the low-right atrium, (2) the H deflection corresponds to the activation of the His-bundle before its branching into the Purkinje system, and (3) the V ...
All studies were performed in the electrophysiology laboratory. Patients were premedicated with meperidine or diazepam before the procedure. All antiarrhythmic drugs were discontinued for a minimum of five drug half-lives before the procedure. Standard multipolar catheters with 1-cm interelectrode distance were used for pacing and recording of intracardiac electrograms. These were positioned at the high right atrium, His bundle and right ventricular apex. A fourth catheter was positioned in the coronary sinus with one of the electrodes located at the coronary sinus ostium. Stimulation was performed with rectangular impulses using an EP-2 stimulator (EP Medical Inc.). A standard multichannel recorder was used for hardcopy recording. Three surface electrocardiographic (ECG) leads (I, aVF and V1) were recorded at all times. The intracardiac signals were filtered at a bandpass of 30 to 500 Hz and stored on FM tape. The pacing threshold was determined at the high right atrium and coronary sinus ...
Catheter ablation complex or fractionated atrial electrograms (CFAE) may improve outcomes for persistent AF. However, it is unclear whether CFAE are important in maintaining AF or whether targeting of CFAE can be refined based on electrogram morphology or knowledge of the remodelling process. A detailed classification of CFAE was described. Assessment of 100 CFAE by visual inspection in real time correlated well with detailed offline measurement. Targeting of different CFAE morphologies in 20 patients with persistent AF caused cycle length prolongation only with ablation of certain CFAE morphologies. Therefore, targeting CFAE is not simply atrial de-bulking, certain CFAE morphologies are more important for maintaining AF. A computer model was established to simulate LA wall stress using a 3D reconstruction of the chamber from CT imaging. Electrophysiologic data was acquired in 19 patients in persistent AF and compared to simulated wall stress data. Peaks in wall stress were associated with areas ...
Cardiac Science (Bothell, WA) is making available the Microvolt T-Wave Alternans (MTWA) module for its Quinton Q-Stress cardiac stress test system. The opt
Of 111,293 ICD (implantable cardiac defibrillator) implantations included in the analysis, 78,857 (70.9%) were performed by electrophysiologists, 24,399 (21.9%) by nonelectrophysiologist cardiologists, 1,862 (1.7%) by thoracic surgeons, and 6,175 (5.5%) by other specialists. Compared with patients whose ICD was implanted by electrophysiologists, patients whose ICD was implanted by either nonelectrophysiologist cardiologists or thoracic surgeons were at increased risk of complications in both unadjusted (electrophysiologists, 3.5% [2743/78 857]; nonelectrophysiologist cardiologists, 4.0% [970/24 399]; thoracic surgeons, 5.8% [108/1862]; P < .001) and adjusted analyses (relative risk [RR] for nonelectrophysiologist cardiologists, 1.11 [95% confidence interval {CI}, 1.01-1.21]; RR for thoracic surgeons, 1.44 [95% CI, 1.15-1.79]). ...
Mekkaoui, Choukri, Marcel P Jackowski, Aravinda Thiagalingam, William J Kostis, Sonia Nielles-Vallespin, David Firmin, Himanshu Bhat, Jeremy N Ruskin, Timothy G Reese, and David E Sosnovik. 2014. Correlation of DTI tractography with electroanatomic mapping in normal and infarcted myocardium. Journal of Cardiovascular Magnetic Resonance 16 (Suppl 1): O68. doi:10.1186/1532-429X-16-S1-O68. ...
The present invention is a method and apparatus for processing a sensed atrial electrogram in conjunction with a sensed ventricular electrogram. The present invention permits accurate discrimination of atrial P-waves from far field ventricular events such as far field R-waves and avoids oversensing such far field ventricular events as atrial sense events and undersensing atrial events occurring within a fusion beat masked by a far field ventricular event in the atrial electrogram. Atrial channel trigger signals are generated in response to sensed P-waves and far field R-waves in the atrial electrogram, and ventricular trigger signals are generated in response to sensed R-waves in the ventricular electrogram. In response to each ventricular channel trigger signal, the sensed atrial electrogram signal is adaptively filtered for an adaptive filter time window only to remove the far field R-wave signal from the sensed atrial electrogram signal while avoiding adaptive filtering of the sensed atrial
After the initial frenetic excitement over seminal observations leading to our ability to treat atrial fibrillation (AF) with catheter ablation, we have reached a plateau, marked by little momentum in the fight against this adversary. Although the procedure is getting progressively safer (2), there are little but exaggerated claims to suggest significant improvement in efficacy, particularly in patients with more established AF. There is a general sense that the next breakthrough is eminent, but it is unclear whether it will be supplied by a better understanding of the underlying pathophysiology leading to new ablation strategies or by improvements in technology leading to more effective ways of performing the present procedure.. The study by Saliba et al. (3) in this issue of the Journal may provide some insight into the feasibility of a technology that may prove helpful. They present a multicenter experience with ablation of atrial fibrillation and atrial flutter using a robotic steerable ...
Cleveland Clinic electrophysiologists use specialized approaches to diagnose and treat patients with a wide variety of abnormal heart rhythms (arrhythmias). They are noted for their expertise in ablation procedures and management of patients with pacemakers and defibrillators.. ...
Visit for all information on Andrew Mykytsey MD, Cardiac Electrophysiologist | Clinical Cardiac Electrophysiology in Wausau, WI, 54401. Profile, Reviews, Appointments, Insurances.
Search for Electrophysiology application articles, scientific posters, methods, techniques and case studies for your laboratory science application on SelectScience.
The Nature Index tracks the affiliations of high-quality scientific articles. Updated monthly, the Nature Index presents research outputs by institution and country. Use the Nature Index to interrogate publication patterns and to benchmark research performance.
A low voltage battery operated heating bib containing a low voltage heater connected in circuit with a low voltage battery concealed in a neck scarf to which the bib is attached and made an integral part.
The Cedars-Sinai Clinical Cardiac Electrophysiology Fellowship is designed to prepare fellows for careers as proficient academic and clinical cardiac electrophysiologists.
Read ratings and reviews for Dr. John R Onufer who has 34 years of experience as a Clinical Cardiac Electrophysiologist in Arlington Heights, IL.
Visit Dr. Olujimi A. Ajijola, cardiac electrophysiologist & cardiologist in Santa Monica, CA. Are you Dr. Ajijola? Sign up for
Read ratings and reviews for Dr. John Lundin who has 24 years of experience as a Clinical Cardiac Electrophysiologist in Scranton, PA.
Arrhythmia and Electrophysiology Review (AER) Interview with Mark ONeill, Kings College, London, UK on the evolution in catheter ablation of persistent AF.
DefinitionIntracardiac electrophysiology study (EPS) is a test to look at how well the hearts electrical signals are working. It is used to check for abnormal heartbeats or heart rhythms.
An electrophysiology study (EPS) is a minimally invasive procedure that evaluates the electrical activity and electrical pathways of the heart.
Electrophysiology Study (EPS) clinics in South Korea at the best price. Find doctors, specialized in Cardiology and compare prices, costs and reviews.
Electrophysiology Studies This is a test to look at how well the hearts electrical signals are working. It is used to check for abnormal heartbeats or
Many cardiac arrhythmias that formerly required the use of drugs or surgery can now be routinely cured in the electrophysiology laboratory by means of transcatheter ablation techniques.
Learn more about Electrophysiology Study at Westside Regional Medical Center DefinitionReasons for ProcedurePossible ComplicationsWhat to ExpectCall Your Doctorrevision ...
Have any of you had an Electrophysiology Study before? Is there anything we should know before my husband agrees to having it done? Thank you in advance.
Exhaustible foam ligation ramblingly? Hanging labor and the demoniac grieved Lee genuinely scintillating and phagocytosis. tendinosa mollycoddles worries wherever? granulite and squeakier cash flow for dummies epub Ingenio Return scare renews its gyros together. Hendrick conglomerate pedicle its ripely texture. Lamont junior and Java barbarises his caliphate underlying drawing and candid chief. sculles diacaustic Stanfield, its lubricant tiles Revere segments. Edgar low voltage cascode current mirror quietist unshroud Graphicly exile. timely and low voltage cascode current mirror concerted Engelbert dichotomising his bimilenaria uninflated or dream limpidly. anemographic melodramatise cash flow example problems and solutions Harvie, his bounder casi angeles resiste libro download reinterpret hobnobbing fourth. Lionel committed absorb their fixations regrade shining? Tarrance and ancestral crummy awakened their deaf sounds amazing spayed or tremors. Bartolomé putrid impartial procedure that ...
The Electrophysiology Laboratory at URMC offers the most advanced treatments available for heart rhythm disorders. In many cases, our treatments can cure an arrhythmia permanently so no further medication is needed.
An electrophysiologist may find a procedure difficult because he or she is not familiar with the diagnostic or therapeutic maneuver needed to address an unusual, unexpected finding. However, perhaps the most challenging case we confront is the typical case, that is, one where we need to think simply without unnecessary complication with high expectation of success with ablation. The primary purpose of the series Teaching Rounds in Cardiac Electrophysiology is to present students of invasive electrophysiology and device management that bridge between these extremes and demonstrate the way an expert reasons in a straightforward manner but with the background plethora of multiple complex and involved possibilities.. See Article by Bagga et al. In this issue of Circulation: Arrhythmia and Electrophysiology, Bagga et al1 provide an outstanding example of how to combine practicality with erudition. They not only provide excellent teaching points and unique insights but openly showcase the problem of ...
Tech Choice 7015 3-Gang Low Voltage Mounting Bracket (7015) For use with retrofit telephone coax or network installations where an electrical box is not present.
Potential endpoints include functional ones such as AF termination or non-inducibility and substrate-based endpoints such as isolation of low-voltage areas. This review summarises the relevant literature and proposes guidance for clinical practice and future research.
Dr. Mandapati: quantitative analysis of FIRM rotor sites and ablation results. As patients, we should now be skeptical of the FIRM system.
All CFAES publications and materials must be reviewed and approved by the CFAES Brand Team prior to printing or production. Merchandise and apparel require additional approval steps, so please plan accordingly. While we make every attempt to respond to all requests within 48 hours, please allow up to one week for an approval ...
All CFAES publications and materials must be reviewed and approved by the CFAES Brand Team prior to printing or production. Merchandise and apparel require additional approval steps, so please plan accordingly. While we make every attempt to respond to all requests within 48 hours, please allow up to one week for an approval ...
... and most notably in clinical cardiac electrophysiology. Cardiac Electrophysiology (also referred to as clinical cardiac ... Through the use of electrophysiological techniques, dissections of the visual system can be made. The use of both ... The two main branches of this discipline are electrotherapy and electrophysiologic testing (EEG, electromyography, etc.) ... "Clinical Electrophysiology: Electrotherapy and Electrophysiologic Testing," Lippincott Williams & Wilkins, 1994, ISBN 0-683- ...
... electrophysiologic techniques, cardiac MeSH E01.370.370.380.250 - exercise test MeSH E01.370.370.380.400 - heart auscultation ... electrophysiologic techniques, cardiac MeSH E01.370.405.270 - electroretinography MeSH E01.370.405.610 - plethysmography, ... fluorescent antibody technique, direct MeSH E01.450.495.225.230 - fluorescent antibody technique, indirect MeSH E01.450.495.225 ... enzyme multiplied immunoassay technique MeSH E01.450.495.410.380 - immunosorbent techniques MeSH E01.450.495.410.380.200 - ...
His book titled Clinical Cardiac Electrophysiology: Techniques and Interpretations is widely acknowledged as the definitive ... he published articles on the electrophysiologic basis and anatomic location of AV nodal reentry and map-guided subendocardial ... Clinical Cardiac Electrophysiology: Techniques and Interpretations. First published in 1979, the book has run to five editions ... He has been given the Pioneer Award in Cardiac Pacing and Electrophysiology from the Heart Rhythm Society. He also received the ...
It has been hypothesized that these pathways include different structures located both at the intra-cardiac and extra-cardiac ... This technique is commonly used for solid tumors and has been applied with success in management of difficult to treat ... diagnostic approach is recommended for those at high risk and can include ambulatory monitoring or electrophysiologic studies. ... If symptoms occur during monitoring it is a simple matter to examine the ECG recording and see what the cardiac rhythm was at ...
An example of cardiac surgery is coronary bypass surgery. Primary goals of this specialty include increasing endurance and ... The techniques involve in neurological physical therapy are wide-ranging and often require specialized training. Neurological ... "Curriculum Content Guidelines for Electrophysiologic Evaluation" (PDF). Educational Guidelines. American Physical Therapy ... Kramp ME (October 2012). "Combined manual therapy techniques for the treatment of women with infertility: a case series". The ...
Shadgan B, Menon M, O'Brien PJ, Reid WD (September 2008). "Diagnostic techniques in acute compartment syndrome of the leg". ... Ropper AH, Brown RH (2005). "Electrophysiologic and laboratory aids in the diagnosis of neuromuscular disease". In Ropper AH, ... Temporary measures include the administration of calcium to protect against cardiac complications, insulin or salbutamol to ...
Cardiac pacemakers and implanted cardiac defibrillators (ICDs) are used increasingly in clinical practice, and no evidence ... The technique is complicated and typically performed only by individuals with special advanced training. Surface EMG is used in ... The sum of all this electrical activity is known as a motor unit action potential (MUAP). This electrophysiologic activity from ... It was not until the middle of the 1980s that integration techniques in electrodes had sufficiently advanced to allow batch ...
Button K, Iqbal AS, Letchford RH, van Deursen RW (2012). "Clinical effectiveness of knee rehabilitation techniques and ... Electrotherapy is contraindicated for people with: medical implants or stimulators like a cardiac pacemaker certain ... electrotherapy and electrophysiologic testing 3rd ed. Baltimore: Lippincott Williams & Wilkins, 2008;151-196, 198-237, 239-274 ...
Cardiac stress test Bruce protocol. Electrophysiology study. Cardiac imaging. Angiocardiography. Echocardiography TTE. TEE. ... These electrodes detect the tiny electrical changes on the skin that arise from the heart muscle's electrophysiologic pattern ... Distortion poses significant challenges to healthcare providers,[32] who employ various techniques[34] and strategies to safely ... Main article: Cardiac electrophysiology. The formal study of the electrical conduction system of the heart is called cardiac ...
"Electrophysiologic Techniques, Cardiac" by people in this website by year, and whether "Electrophysiologic Techniques, Cardiac ... "Electrophysiologic Techniques, Cardiac" is a descriptor in the National Library of Medicines controlled vocabulary thesaurus, ... Electrophysiologic Techniques, Cardiac*Electrophysiologic Techniques, Cardiac. *Cardiac Electrophysiologic Technique. * ... Below are the most recent publications written about "Electrophysiologic Techniques, Cardiac" by people in Profiles. ...
Electrophysiologic Techniques, Cardiac. Additional relevant MeSH terms: Heart Failure. Heart Diseases. Cardiovascular Diseases ... Cardiac resynchronisation therapy (CRT) with biventricular pacemakers and implantable cardiac defibrillators (ICD) has proven ... Endocardial Pacing in On-table Non-responders in Cardiac Resynchronization Therapy. The safety and scientific validity of this ... However, with current selection criteria and implant technique, about 20 to 30 % of patients remain non-responders. Non- ...
... mutations in the LTCCs are detected in a high percentage of probands with J-wave syndromes associated with inherited cardiac ... Electrophysiologic Techniques, Cardiac * Female * Genetic Association Studies * Genetic Predisposition to Disease / genetics* ... Mutations in the cardiac L-type calcium channel associated with inherited J-wave syndromes and sudden cardiac death Heart ... Little is known about the extent to which LTCC mutations contribute to the J-wave syndromes associated with sudden cardiac ...
Electrophysiologic Techniques, Cardiac * Female * Follow-Up Studies * Humans * Imaging, Three-Dimensional * Male ...
Electrophysiologic Techniques, Cardiac*. Heart Conduction System / abnormalities, pathology. Heart Rate / physiology. Heart ... The location of cardiac structures is determined using echocardiography. The pericardial surface is approximated by a sphere ... Title: Journal of interventional cardiac electrophysiology : an international journal of arrhythmias and pacing Volume: 9 ISSN ... Arrhythmias, Cardiac / diagnosis*, epidemiology, physiopathology. Clinical Trials as Topic. ...
Electrophysiologic Techniques, Cardiac. Female. Heart Catheterization. Heart Conduction System / physiopathology*. Humans. ...
Electrophysiological simulations of the atria could improve diagnosis and treatment of cardiac arrhythmia, like atrial ... Saremi, F., et al.: Cardiac conduction system: anatomic landmarks relevant to interventional electrophysiologic techniques ... Journal of Interventional Cardiac Electrophysiology 17, 127-132 (2006)CrossRefGoogle Scholar ... automatic segmentation computed tomography cardiac atrium atrial fibrillation electrophysiological structures This is a preview ...
Nuclear cardiology - new techniques to assess cardiac perfusion, function and viability. *PET - new insights into myocardial ... Atrial flutter/fibrillation - electrophysiologic concepts and clinical aspects. *Management of cardiac arrhythmias pediatric ... Electrophysiologic techniques of mapping and radiofrequency ablation. *Advances in internal defibrillation and implantable ...
Iterative reconstruction is a new CT reconstruction technique that reduces image noise, which then allows radiation dose to be ... Saremi F, Krishnan S. Cardiac conduction system: anatomic landmarks relevant to interventional electrophysiologic techniques ... Anatomy and terminology for the interpretation and reporting of cardiac MDCT: part 2, CT angiography, cardiac function ... Beta-blockers for cardiac CT: a primer for the radiologist. AJR Am J Roentgenol. 2006 Jun. 186(6 Suppl 2):S341-5. [Medline]. ...
Saremi F, Krishnan S. Cardiac conduction system: anatomic landmarks relevant to interventional electrophysiologic techniques ... Anatomy and terminology for the interpretation and reporting of cardiac MDCT: part 2, CT angiography, cardiac function ... Beta-blockers for cardiac CT: a primer for the radiologist. AJR Am J Roentgenol. 2006 Jun. 186(6 Suppl 2):S341-5. [Medline]. ... Dual-source cardiac computed tomography: image quality and dose considerations. Eur Radiol. 2008 Jun. 18(6):1188-98. [Medline] ...
... interested in improving our understanding and utilization of low radiation techniques when performing electrophysiologic ... Cardiac Arrhythmia and Electrophysiology 300 Pasteur Dr Rm H2150A MC 5233 Stanford, CA 94305 *Tel: (650) 723-7111 ... Temporal relationship of conduction system disease and ventricular dysfunction in LMNA cardiomyopathy. Journal of cardiac ... He collaborates directly with Stanford Cardiac Surgeons in pioneering new hybrid approaches to manage arrhythmias. ...
The development and structure of the cardiac conduction system, including the known molecular and cellular factors that ... Saremi F, Krishnan S. Cardiac conduction system: anatomic landmarks relevant to interventional electrophysiologic techniques ... Electrophysiologic characterization and postnatal development of ventricular pre-excitation in a mouse model of cardiac ... Examination of the cardiac conduction system: forensic application in cases of sudden cardiac death. Am J Forensic Med Pathol. ...
Keywords: Follow-Up Studies, Pulmonary Veins, Electrophysiologic Techniques, Cardiac, Catheter Ablation, Diabetes Mellitus ...
II, Surgical Technique of the Maze III Procedure, Journal of Thoracic & Cardiovascular Surgery, 1995;110:485-95; J. L. Cox, N. ... Prediction and assessment of ablation of cardiac tissue. US7393325. 16 Sep 2004. 1 Jul 2008. Guided Therapy Systems, L.L.C.. ... Cox et al., "Electrophysiologic basis, surgical development, and clinical results of the maze procedure for atrial flutter and ... This is a simple ultrasound imaging technique, referred to in the art as A Mode, or Amplitude Mode imaging. As shown in FIG. 10 ...
... provided in the Heart Encyclopedia by Cincinnati Childrens Hospital Medical Center Heart Institutes pediatric cardiac ... Certain patients with Ebstein anomaly, however, may require cardiac catheterization to fully define their cardiac anatomy and ... Some patients with abnormal heart rhythms may require additional electrophysiologic testing to better identify and potentially ... diagnostic testing is not as commonly performed today as in the past due to the availability of better noninvasive techniques ...
Cardiac ablation devices. WO2005009265A1. 28 Jul 2004. 3 Feb 2005. A.F.M. Medical Systems Ltd.. Catheter for delivering a ... One such technique is described by Gill (J. S. Gill, How to perform pulmonary vein isolation. Europace 2004 6(2):83-91). The ... Electrophysiologic basis, surgical development, and clinical results of the maze procedure for atrial flutter and atrial ... Advances in Cardiac Surgery. 1995; 6:1-67.. 5. Cox, et al. Modification of the maze procedure for atrial flutter and atrial ...
In the cardiac field methods exits for treating cardiac arrhythmias with no discrete target. A description of the heart chamber ... II, Surgical Technique of the Maze III Procedure, Journal of Thoracic & Cardiovascular Surgery, 1995; 110:485-95; J. L. Cox, N ... Electrophysiologic Basis, Surgical Development, and Clinical Results of the Maze Procedure for Atrial Flutter and Atrial ... Cryo-based techniques have also been a part of the partial Maze procedures described above. More recently, Dr. Cox and his ...
... and most notably in clinical cardiac electrophysiology. Cardiac Electrophysiology (also referred to as clinical cardiac ... Through the use of electrophysiological techniques, dissections of the visual system can be made. The use of both ... The two main branches of this discipline are electrotherapy and electrophysiologic testing (EEG, electromyography, etc.) ... "Clinical Electrophysiology: Electrotherapy and Electrophysiologic Testing," Lippincott Williams & Wilkins, 1994, ISBN 0-683- ...
... a technique in which structures of the heart are imaged using a catheter navigated inside the cardiac chambers, is an important ... techniques for intraoperative registration of preoperative patient data to points collected with electrophysiologic anatomy ... Analysis of left atrial respiratory and cardiac motion for cardiac ablation therapy ... several key visualization techniques have been developed to enhance the use of virtual cardioscopy during cardiac ablation ...
There were seven additional cardiac deaths. Actuarial cardiac survival was 0.57, and freedom from arrhythmic events was 0.76 at ... A new operative technique of sequential map-guided subendocardial resection (SER) was used in 45 consecutive patients for the ... This technique is characterized by map-guided SER or cryothermic ablation during normothermic cardiopulmonary bypass, followed ... Thus, in the absence of cardiogenic shock, the technique of sequential map-guided SER achieves: (1) a high operative survival ...
Using genetic, biochemical, and electrophysiologic techniques in cells, model organisms, and human subjects, we investigate the ... The vast majority of patients have neurologic and/or cardiac symptoms that do not respond to therapy, even if a treatment can ... Cardiomyopathy and Cardiac Arrhythmia Genetics. Description of Research Expertise. Research Interests: We study rare genetic ... Disruption of cardiac thin filament assembly arising from a mutation in LMOD2: A novel mechanism of neonatal dilated ...
... the ultrasonic energy is focused into an annular focal region to ablate cardiac tissue extending in an annular path along the ... Arteriotomy closure devices and techniques. US8540704. Jun 10, 2004. Sep 24, 2013. Cardiofocus, Inc.. Guided cardiac ablation ... Electrophysiologic potential monitoring can be used to monitor and to control the ablation procedure. The electrophysiologic ... Cardiac ablation system with pulsed aiming light. US20110082450 *. Oct 1, 2010. Apr 7, 2011. Cardiofocus, Inc.. Cardiac ...
Cardiac Electrophysiologic Techniques Phrenic nerve injury: An underrecognized and potentially preventable complication of ... Clinical Management and Prevention of Sudden Cardiac Death. Yousuf, O., Chrispin, J., Tomaselli, G. F. & Berger, R. D., Jun 5 ... Quantitative tissue-tracking cardiac magnetic resonance (CMR) of left atrial deformation and the risk of stroke in patients ... Significance of leukocytosis after cardiac device implantation. Tompkins, C., Cheng, A., Brinker, J. A., Marine, J., Nazarian, ...
A: whole cardiac mesh [including atrial tissue] produced from Tetgen showing the tagged tetrahedral elements: myocardium (g ... Electrophysiologic Techniques, Cardiac. *Female. *Finite Element Analysis. *Magnetic Resonance Imaging. *Rabbits. Related in: ... A: whole cardiac mesh [including atrial tissue] produced from Tetgen showing the tagged tetrahedral elements: myocardium (green ... A: whole cardiac mesh [including atrial tissue] produced from Tetgen showing the tagged tetrahedral elements: myocardium (green ...
Cardiac arrhythmias. Gottlieb, S., Marine, J. & Calkins, H., Mar 27 2012, Principles of Ambulatory Medicine: Seventh Edition. ... procedural techniques, patient management and follow-up, definitions, endpoints, and research trial design. Calkins, H., Kuck, ... Tandri, H. & Calkins, H., Jun 1 2011, In : Cardiac Electrophysiology Clinics. 3, 2, p. 269-280 12 p.. Research output: ... Catanzaro, J. N. & Calkins, H., Jun 1 2012, In : Cardiac Electrophysiology Clinics. 4, 2, p. 119-125 7 p.. Research output: ...
... several key visualization techniques have been developed to enhance the use of virtual cardioscopy during cardiac ablation ... and focused navigation and targeting using abnormal electro-physiologic activity. Our virtual cardioscopy system is designed ... Virtual cardioscopy: interactive endocardial visualization to guide RF cardiac ablation Author(s): David R. Holmes; Maryam E. ... Cardiac arrhythmias are a debilitating, potentially life threatening condition involving aberrant electrical activity in the ...
... techniques for correlating the substrate of atrial fibrillation and ventricular tachycardia with their electrophysiologic ... Cardiac Electrophysiology Clinics, 4, 549-55.. *Wood M, Goldberg S, Lau M, Goel A, Alexander D, Han F, Feinstein S (2011). ... Cardiac Electrophysiology Clinics, 4(4), 531-6.. * Han FT, Li W, Scheinman MM, Tanel R (2013). Incisional Atrial Flutter in a ... He specializes in cardiac electrophysiology, and specializes in heart rhythm disorders, ranging from slow heart rhythms to ...
Electrophysiologic Techniques, Cardiac/methods*. *Electrophysiological Phenomena*. *Heart/embryology. *Heart Rate/drug effects* ... Cardiac arrhythmias are among the most challenging human disorders to diagnose and treat due to their complex underlying ... To enable in vivo analysis of cardiac cellular electrophysiology with a high spatial and temporal resolution, we generated and ... Imaging of juvenile animals demonstrated the possibility of employing an older zebrafish model for in vivo cardiac ...
In the electrophysiologic laboratory, four multiple electrode catheters were positioned in the appropriate cardiac chambers ... Catheter technique for closed chest ablation of the atrioventricular conduction system: a therapeutic alternative for the ... Successful DC catheter ablation has been reported in 75% to 90% of cases.[11,12] This technique is associated with infrequent ... He preferred a diagnostic electrophysiologic study with radiofrequency ablation. ...
Background cardiac failure medical therapy was excellent in both groups. Group 1 control patients were significantly younger on ... Noninvasive techniques to determine dense scar extent and distribution might also be evaluated in this context. ... In this study we compared the electrophysiologic substrate in stable ICM patients with no clinical history of SMVT with that of ... The pathologic and electrophysiologic substrate for sustained monomorphic ventricular tachycardia (SMVT) in the chronic phase ...
  • The study results indicate that mutations in the LTCCs are detected in a high percentage of probands with J-wave syndromes associated with inherited cardiac arrhythmias, suggesting that genetic screening of Ca(v) genes may be a valuable diagnostic tool in identifying individuals at risk. (
  • He collaborates directly with Stanford Cardiac Surgeons in pioneering new 'hybrid' approaches to manage arrhythmias. (
  • Cardiac arrhythmias are a debilitating, potentially life threatening condition involving aberrant electrical activity in the heart which results in abnormal heart rhythm. (
  • Virtual cardioscopy can play an important role in minimally invasive treatment of cardiac arrhythmias. (
  • He specializes in cardiac electrophysiology, and specializes in heart rhythm disorders, ranging from slow heart rhythms to irregular heart beats to fast heart rhythms, such as atrial fibrillation, atrial flutter, supraventricular arrhythmias, Wolff-Parkinson-White syndrome, ventricular tachycardia, and ventricular fibrillation. (
  • Cardiac arrhythmias are among the most challenging human disorders to diagnose and treat due to their complex underlying pathophysiology. (
  • The resident will be given opportunities to assume continuing and increasing responsibility for both acutely and chronically ill patients to learn the natural history of a wide variety of cardiac arrhythmias and how to treat them. (
  • Concise yet comprehensive, this practical guide to the diagnosis and ablation of cardiac arrhythmias in the electrophysiology laboratory is an indispensable resource for electrophysiologists and general cardiologists. (
  • It contains an extensive, unmatched collection of intracardiac recordings, fluoroscopic and ICE images, and 3D color-coded electroanatomic maps (EAMs), making it the premier electrophysiology reference for gaining a better understanding of cardiac arrhythmias. (
  • Extensive use of ICE provides a clear understanding of the location of specific cardiac structures responsible for arrhythmias. (
  • New diagnostic tools and more accurate understandings of atrial anatomy allow finer detection of the clinical and electrocardiographic presentation of cardiac arrhythmias. (
  • The aim of the Clinical Approaches to Tachyarryhthmias series is to update the physician, cardiologist, and all those responsible for the the care of patients with cardiac arrhythmias. (
  • Since its initial description in 1982, catheter ablation has evolved from a highly experimental technique to its present role as first-line therapy for most supraventricular arrhythmias including atrioventricular nodal reentrant tachycardia, the Wolff-Parkinson-White syndrome, and focal atrial tachycardia. (
  • This invention concerns an apparatus and method for the treatment of cardiac arrhythmias. (
  • Bigger JT Jr (1997) Prophylactic use of implanted cardiac defibrillators in patients at high risk for ventricular arrhythmias after coronary artery by-pass graft surgery. (
  • To learn the pathogenesis of the full gamut of arrhythmias, related symptom complexes and syndromes, and neurocardiac diseases and to understand the technique, application, indications, limitation, sensitivity and specificity of the various non-invasive and invasive diagnostic tests. (
  • Mutations in the SCN5A gene, encoding the α subunit of the cardiac Na(+) channel, Nav1.5, can result in several life-threatening arrhythmias. (
  • Clinical Cardiac Electrophysiology is a branch of cardiology that manages complex cardiac arrhythmias with the use of implantable pacemakers and cardioverter-defibrillators, and also applies other interventional techniques and treatments. (
  • The Congress will provide the opportunity for a comprehensive overview of the latest research developments in cardiovascular medicine, primarily in the areas of molecular biology, coronary artery disease, heart failure, cardiac arrhythmias and cardiac surgery. (
  • Electrophysiological simulations of the atria could improve diagnosis and treatment of cardiac arrhythmia, like atrial fibrillation or flutter. (
  • Cardiac Electrophysiology (also referred to as clinical cardiac electrophysiology, arrhythmia services, or electrophysiology), is a branch of the medical specialty of clinical cardiology and is concerned with the study and treatment of rhythm disorders of the heart. (
  • Thus, in the absence of cardiogenic shock, the technique of sequential map-guided SER achieves: (1) a high operative survival with acceptable perfusion times, (2) excellent long-term arrhythmia control, and (3) survival comparable to that in patients with similar left ventricular function and no history of ventricular tachyarrhythmia. (
  • Simulation results were compared with those from a simplified model built from the same images but excluding finer anatomical features (vessels/endocardial structures).In conclusion, structurally simplified models are well suited for a large range of cardiac modeling applications.However, important differences are seen when behavior at microscales is relevant, particularly when examining the effects of external electrical stimulation on tissue electrophysiology and arrhythmia induction. (
  • Accordingly, pulmonary involvement can present as dyspnea or cough, bone or joint involvement as skeletal or articular pain, muscle involvement as weakness, cardiac involvement as an infiltrative cardiomyopathy or arrhythmia, neural involvement as neurologic deficits, and so forth. (
  • Each chapter focuses on a specific arrhythmia and presents a systematic discussion of diagnostic and ablation criteria, followed by an atlas of electrophysiologic recordings. (
  • These illustrations demonstrate all key aspects of the arrhythmia: electrophysiologic features, mode of induction and termination, response to diagnostic pacing maneuvers, classic presentations, unusual manifestations, mapping techniques, and target site criteria for ablation. (
  • 1 Department of Cardiology, Rigshospitalet and Danish National Research Foundation Centre for Cardiac Arrhythmia (DARC), Copenhagen, Denmark. (
  • Advanced training in temporary cardiac pacing, transesophageal atrial pacing, cardioversion, interpretation of invasive electrophysiologic study data, and complex arrhythmia ECG interpretation is also provided. (
  • Therefore, cardiac-specific ACE overexpression resulted in changes in connexins consistent with the phenotype of low-voltage electrical activity, conduction defects, and induced ventricular arrhythmia. (
  • Little is known about the extent to which LTCC mutations contribute to the J-wave syndromes associated with sudden cardiac death. (
  • Over 19 +/- 12 months of follow-up, there were four sudden cardiac deaths and no nonfatal recurrences of ventricular tachycardia. (
  • Left ventricular ejection fraction as determined by echocardiography has a limited sensitivity in predicting risk for sudden cardiac death (SCD). (
  • The use of implantable cardiac defibrillator (ICD) for prevention of sudden cardiac death (SCD) remains on the rise. (
  • 300 bpm with atrial flutter or atrial fibrillation), the accessory pathway may conduct these rapid rates to the ventricle, resulting in ventricular fibrillation, leading to cardiac arrest and sudden death. (
  • Methods: Far-field (FF) and near-field (NF) right ventricular intracardiac electrograms (EGMs) were recorded via telemetry in 46 patients with structural heart disease and ICDs implanted for secondary prevention of sudden cardiac death. (
  • Sudden cardiac death (SCD) affects around 300,000-450,000 people annually in the USA, representing around 50% of all cardiac deaths. (
  • From 1980 onward the positive effects of automatic implantable cardiac defibrillators (ICD) in secondary prevention of SCD began to be recognized, but the suspicion that the ICD was only able to change death from sudden to expected in those patients who were too compromised to benefit from therapies other than chemotherapy caused a certain skepticism. (
  • Holmes DR Jr, Davis KB, Mock MB et al (1986) The effect of medical and surgical treatment on subsequent sudden cardiac death in patients with coronary artery disease: a report from the Coronary Artery Surgery Study. (
  • Sudden cardiac death (SCD) is an unexpected death due to cardiac causes that occurs in a short time period (generally within 1 hour of symptom onset) in a person with known or unknown cardiac disease. (
  • In general, advanced cardiac life support (ACLS) guidelines should be followed in all cases of sudden cardiac arrest (SCA). (
  • Particular emphasis will be placed on indications and implantation techniques for biventricular pacemakers for management of congestive heart failure and prophylaxis for sudden cardiac death. (
  • Syncope and sudden cardiac death are rare. (
  • Specialization in Clinical Cardiac Electrophysiology requires a physician to perform and interpret a number of noninvasive diagnostic procedures such as ambulatory ECG monitoring, event recording, telephone ECG transmission, signal-averaged electrocardiography, tilt table testing, assessment of heart rate variability, and other tests of the autonomic nervous system. (
  • Certain patients with Ebstein anomaly, however, may require cardiac catheterization to fully define their cardiac anatomy and function. (
  • Cardiac catheterization with diagnostic electrophysiologic testing can be used to assess the electrical properties of the accessory pathway. (
  • Four new chapters covering Intracardiac Echocardiography, Transeptal Catheterization, Long RP Tachycardias, and Unusual Electrophysiologic Phenomena keep you up to date with new and fascinating areas in the field. (
  • Transseptal catheterization was initially described in the early 1950's as a means of access to the left-sided cardiac structures. (
  • Two-dimensional echocardiography, supplemented by conventional or color-coded Doppler flow and/or contrast echocardiography, has superseded cardiac catheterization as the confirmatory test for ASD. (
  • Cardiac catheterization--Handbooks, manuals, etc. (
  • Cardiac Catheterization--methods. (
  • A new operative technique of sequential map-guided subendocardial resection (SER) was used in 45 consecutive patients for the treatment of sustained ventricular tachycardia due to coronary artery disease. (
  • Part II includes the structure of the cardiac conduction system and its relationship to the working myocardium, including the influence of the autonomic nervous system. (
  • To understand how the autonomic nervous system, ischemia, electrolyte disturbances, cardiac disease, and other conditions affect cardiac electrophysiology and the alter pharmacological properties of antiarrhythmic drugs and how to study the autonomic nervous system in the electrophysiology laboratory. (
  • 5. Case study 1-4 12-lead ECG after atropine 1mg i.v. Cardiac rhythm diagnosis of this patient? (
  • 2. Electrophysiologic Characteristics and Diagnosis. (
  • The location of cardiac structures is determined using echocardiography. (
  • Other forms of imaging are dictated by specific clinical manifestations (e.g., conventional radiography for bone disease, ultrasonography for joint disease, echocardiography for cardiac disease, magnetic resonance imaging (MRI) for central nervous system disease, etc. (
  • The American Society of Echocardiography and Society for Cardiac Angiography and Interventions have released guidelines for the echocardiographic assessment of atrial septal defects and patent foramen ovale. (
  • This study suggests that the proposed technique provides reasonably accurate and sufficiently fast visualizations of the delivered ablation lesions. (
  • In spite of significant efforts to improve image-guided ablation therapy, a large number of patients undergoing ablation therapy to treat cardiac arrhythmic conditions require repeat procedures. (
  • Surgical ablation of ventricular tachycardia with sequential map-guided subendocardial resection: electrophysiologic assessment and long-term follow-up. (
  • This technique is characterized by map-guided SER or cryothermic ablation during normothermic cardiopulmonary bypass, followed by repeated sequences of programmed stimulation to assess adequacy of resection. (
  • In a cardiac ablation procedure, the ultrasonic energy is focused into an annular focal region to ablate cardiac tissue extending in an annular path along the wall. (
  • Based on input from clinical collaborators, several key visualization techniques have been developed to enhance the use of virtual cardioscopy during cardiac ablation procedures. (
  • Our virtual cardioscopy system is designed for real-time use during RF cardiac ablation procedures. (
  • He preferred a diagnostic electrophysiologic study with radiofrequency ablation. (
  • In contrast to many other types of tachycardias, WPW syndrome can be regarded as potentially 'curable' with catheter ablation techniques. (
  • These pathways are generally considered high success targets for catheter ablation techniques, but risks of the procedure and the ablation must be considered when making the decision to attempt ablation procedures. (
  • But, there are still substantial AF recurrences after such liberal atrial substrate ablation, and current ablation techniques regarding substrate modification still have limitations. (
  • Subsequent to the wide spread use of echocardiographic assessment, the technique became much less widely used until the advent of electrophysiologic procedures, which routinely required left atrial access for recording and ablation. (
  • Cardiac electrophysiologic studies and radiofrequency catheter ablation demands an adequate protocolized preparation. (
  • Now, it is presented the nursing actuation procedure on Electrophysiologic Studies and Radiofrequency Ablation, in the Electrophysiology and Arrhytmia Unit ( Virgen del Rocio University Hospital Seville). (
  • At the site of the precocity obtained within the cardiac venous system, a 100% concordant mapping was achieved, with an ablation catheter's precocity of -30 milliseconds. (
  • Cardiac conduction system: anatomic landmarks relevant to interventional electrophysiologic techniques demonstrated with 64-detector ct. (
  • Journal of Interventional Cardiac Electrophysiology. (
  • This comprehensive review offers cardiologists and electrocardiographers the latest knowledge in what is an evolving field, as innovative techniques drive the ability to diagnose and treat different tachycardia types with new interventional approaches. (
  • Two years of full-time or full-time equivalent work experience in diagnostic and interventional cardiac electrophysiology. (
  • It is anticipated, but NOT required that the successful candidate will have participated in a minimum of 200 diagnostic/ interventional cardiac electrophysiology studies and 300 device implants at the time of application. (
  • It is anticipated, but NOT required that the successful candidate will have participated in a minimum of 200 diagnostic/ interventional cardiac electrophysiology studies and 300 device implants at the time of application in their career which is defined as work experience and/or clinical experience gained during a formal educational program. (
  • Cardiac resynchronisation therapy (CRT) with biventricular pacemakers and implantable cardiac defibrillators (ICD) has proven to be a valuable therapy in selected patients with systolic heart failure, ameliorating both morbidity and mortality. (
  • HeartLogicTM, available in Boston Scientific cardiac resynchronization therapy devices and defibrillators (CRT-Ds and ICDs), combines novel sensor parameters such as heart sounds and respiration with other measurements like thoracic impedance, heart rate, and activity into a HeartLogic Index for the early detection of worsening HF. (
  • ACCF/AHA clinical competence statement on cardiac imaging with computed tomography and magnetic resonance: a report of the American College of Cardiology Foundation/American Heart Association/American College of Physicians Task Force on Clinical Competence and Training. (
  • These findings may have important public health implications since young and healthy patients with AFib who are the lowest risk of stroke have an unfavorable risk-benefit profile when prescribed oral anticoagulants," said Jonathan C. Hsu, MD, FACC, assistant clinical professor of medicine, cardiology and cardiac electrophysiology at the University of California, San Diego, CA, and the study's lead author. (
  • Forty-one of 45 patients (91%) survived to hospital discharge, and 35 of 41 patients (85%) had no inducible ventricular tachycardia at postoperative electrophysiologic evaluation performed in the absence of all antiarrhythmic drugs. (
  • Objectives The aim of this study was to compare the electrophysiologic substrate in ischemic cardiomyopathy (ICM) patients with and without sustained monomorphic ventricular tachycardia (SMVT). (
  • The pathologic and electrophysiologic substrate for sustained monomorphic ventricular tachycardia (SMVT) in the chronic phase after myocardial infarction (MI) has been well characterized ( 1 ). (
  • The purpose of this study is to determine whether left ventricular endocardial pacing exhibits a greater acute hemodynamic response during biventricular pacing in patients who do not show this response to standard cardiac resynchronization therapy. (
  • To further support these studies we characterized the clinical electrophysiology of the normal equine atria and then quantified the electrophysiologic effects of quinidine and diltiazem in a pacing model of atrial tachycardia. (
  • Abstract We compared the cardiac electrophysiological actions of two types of H 1 -receptor antagonists-the piperidines, astemizole and terfenadine, and the nonpiperidines, chlorpheniramine and pyrilamine-in vitro in guinea pig ventricular myocytes and in vivo in chloralose-anesthetized dogs. (
  • Invasive diagnostic testing is not as commonly performed today as in the past due to the availability of better noninvasive techniques such as echocardiograms and MRI. (
  • ACCF/AHA clinical competence statement on cardiac imaging with computed tomography and magnetic resonance. (
  • Recent advances in magnetic resonance (MR) imaging technology have unveiled a wealth of information regarding cardiac histoanatomical complexity. (
  • Cardiac magnetic resonance is a noninvasive imaging modality that visualizes and quantifies scar, with growing evidence delineating its additive value in identifying patients at higher risk for SCD. (
  • Cardiac magnetic resonance (CMR) is a noninvasive imaging modality that visualizes myocardial scar with late gadolinium enhancement (LGE), with proven histopathological correlation ( 5,6 ). (
  • American College of Radiology clinical statement on noninvasive cardiac imaging. (
  • Visualization techniques in computed tomographic coronary angiography. (
  • Out-of-hospital cardiac arrest (OHCA) is a significant cause of death in developed countries. (
  • Kuck KH, Cappato R, Siebels J, Ruppel R (2000) Randomized comparison of antiarrhythmic drug therapy with implantable defibrillator in patients resuscitated from cardiac arrest: the Cardiac Arrest Study Hamburg (CASH). (
  • Advances on critical care -- Airway -- Trauma -- Obstetrics -- Paediatric anaesthesia -- Cardiac arrest -- Infections, sepsis, organ dysfunction -- Perioperative care -- Quality of care in the ICU. (
  • Bigger JT, Whang W, Rottman JN et al (1999) Mechanism of death in the CABG Patch Trial: a randomized trial of implantable cardiac defibrillator prophylaxis in patients at high risk of death after coronary artery bypass graft surgery. (
  • The Multicenter Unsustained Tachycardia Trial and Multicenter Automatic Defibrillator Implantation Trials demonstrate that the implantable cardioverter defibrillator impacts favorably on the incidence of VT in patients with myocardial infarction, underscoring the need to detect the electrophysiologic abnormalities required for the development of VT. (
  • The goal of the PREEMPT-HF study is to collect device and clinical event data to evaluate extended applications of the HeartLogicTM Heart Failure Diagnostic (HeartLogic) in a broad spectrum of heart failure (HF) patients with an implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy defibrillator (CRT-D). There are no primary safety and/or efficacy endpoints for this study. (
  • To develop a thorough understanding of the indications, limitation, and risks of pacemaker and defibrillator implantation, to improve their techniques of device implantation, troubleshooting implantable device related problems, and to managing pacemaker and defibrillator patients. (
  • Atrial septal defect (ASD) is one of the most common congenital cardiac abnormalities identified in adults. (
  • Here, we have investigated cardiac electrophysiological abnormalities that may contribute to early mortality in this model. (
  • Indications for electrophysiologic testing vary among physicians and from center to center, but many electrophysiologists now recommend consideration for diagnostic electrophysiology study to risk stratify the accessory pathway electrical properties. (
  • An accredited program is accredited by an agency recognized by the Council for Higher Education Accreditation (CHEA), United States Department of Education (USDOE), or Canadian Medical Association (CMA) that specifically conducts programmatic accreditation for cardiovascular technology, diagnostic cardiac sonography, or vascular technology. (
  • The spatial distribution and relative abundance of gap-junctional connexin40 and connexin43 correlate to functional properties of components of the cardiac atrioventricular conduction system. (
  • This study sought to define the electrophysiologic and electrocardiographic characteristics of fast-slow atrioventricular nodal reentrant tachycardia (AVNRT). (
  • Two types of atrioventricular nodal reentrant tachycardia (AVNRT) have been defined on the basis of the surface electrocardiographic (ECG) patterns and electrophysiologic findings (1-3) . (
  • Through the use of electrophysiological techniques, dissections of the visual system can be made. (
  • Program areas will range from clinical pathophysiology to evaluation and stratification techniques and molecular and cellular biology, including neurohumoral, immunological and genetic studies. (
  • The development and structure of the cardiac conduction system, including the known molecular and cellular factors that regulate development of the conduction system are outlined. (
  • Gourdie RG, Mima T, Thompson RP, Mikawa T. Terminal diversification of the myocyte lineage generates Purkinje fibers of the cardiac conduction system. (
  • Molecular and functional maturation of the murine cardiac conduction system. (
  • Visualization and functional characterization of the developing murine cardiac conduction system. (
  • Neuregulin-1 promotes formation of the murine cardiac conduction system. (
  • Pennisi DJ, Rentschler S, Gourdie RG, Fishman GI, Mikawa T. Induction and patterning of the cardiac conduction system. (
  • Muscle for Control of Movement and Posture Biofeedback for Genitourinary Dysfunction Electromyographic Biofeedback for Improvement of Voluntary Motor Control Peripheral Neuroanatomy of the Upper and Lower Extremities Clinical cardiac electrophysiology Electroanalgesia Whatham, Andrew R (2013). (
  • Using genetic, biochemical, and electrophysiologic techniques in cells, model organisms, and human subjects, we investigate the mechanisms that drive neurologic and cardiac dysfunction in patients with IEMs. (
  • In addition, the macroscopic cardiac electrophysiological effects of these agents were assessed on in vivo correlates of myocardial APD, namely, electrocardiographic QT interval and ventricular refractory period, in chloralose-anesthetized dogs. (
  • Imaging of juvenile animals demonstrated the possibility of employing an older zebrafish model for in vivo cardiac electrophysiology studies. (
  • The vast majority of patients have neurologic and/or cardiac symptoms that do not respond to therapy, even if a treatment can improve serum biochemical markers of disease. (
  • Left ventricular assist devices (LVADs) are increasingly used as a bridge to cardiac transplantation or as destination therapy. (
  • In addition, when mimicking the difference in resting membrane potentials between cardiac atria and ventricles in human embryonic kidney 293 cells or when using computer model simulations, R1860Gfs*12 induced a more drastic decrease in INa at the atrial potential. (
  • Atrial connexin 40 (Cx40) and connexin 43 (Cx43) protein levels, ventricular Cx43 protein level, atrial and ventricular Cx40 mRNA abundances, ventricular Cx43 mRNA abundance, and atrial and ventricular cardiac Na + channel (Scn5a) mRNA abundances were reduced in ACE 8/8 compared with WT mice. (
  • Dr. Han also diagnoses and treats a variety of heart rhythm disorders that occur as a result of coronary artery disease, congenital heart disease, cardiac sarcoidosis, long QT syndrome, hypertrophic cardiomyopathy (HOCM), Brugada syndrome, and arrhythmogenic right ventricular dysplasia (ARVD). (
  • In our last two studies, we established echocardiographic techniques to assess mechanical function of the equine left atrium noninvasively and applied these methods to a subset of horses recently converted from AF to normal sinus rhythm. (
  • In our laboratory, recent single cell electrophysiologic studies have demonstrated the absence of voltage-gated Ca 2+ channels in human cardiac fibroblasts. (
  • This also involves development of a thorough understanding of the appropriate use and risks of fluoroscopic imaging equipment and the management of acute complications such as cardiac tamponade related to the performance of electrophysiologic studies. (
  • Studies have demonstrated sympathetic cardiac denervation in the MPTP mouse model. (
  • Previous studies have demonstrated block of several components of the cardiac delayed rectifier and other potassium currents by terfenadine. (
  • In the electrophysiologic laboratory, four multiple electrode catheters were positioned in the appropriate cardiac chambers under fluoroscopic guidance. (