Systole: Period of contraction of the HEART, especially of the HEART VENTRICLES.Aorta: The main trunk of the systemic arteries.Aorta, Thoracic: The portion of the descending aorta proceeding from the arch of the aorta and extending to the DIAPHRAGM, eventually connecting to the ABDOMINAL AORTA.Aorta, Abdominal: The aorta from the DIAPHRAGM to the bifurcation into the right and left common iliac arteries.Diastole: Post-systolic relaxation of the HEART, especially the HEART VENTRICLES.Myocardial Contraction: Contractile activity of the MYOCARDIUM.Mitral Valve: The valve between the left atrium and left ventricle of the heart.Heart Ventricles: 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.Blood Flow Velocity: A value equal to the total volume flow divided by the cross-sectional area of the vascular bed.Echocardiography: Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues. The standard approach is transthoracic.Kinetocardiography: The graphic recording of chest wall movement due to cardiac impulses.Ventricular Function, Left: 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.Ventricular Function: The hemodynamic and electrophysiological action of the HEART VENTRICLES.Heart: The hollow, muscular organ that maintains the circulation of the blood.Models, Cardiovascular: 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.Echocardiography, Doppler: Measurement of intracardiac blood flow using an M-mode and/or two-dimensional (2-D) echocardiogram while simultaneously recording the spectrum of the audible Doppler signal (e.g., velocity, direction, amplitude, intensity, timing) reflected from the moving column of red blood cells.Cardiac Volume: 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.Aortic Diseases: Pathological processes involving any part of the AORTA.Atrial Function, Left: The hemodynamic and electrophysiological action of the LEFT ATRIUM.Blood Pressure: PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.Cardiac-Gated Imaging Techniques: Timing the acquisition of imaging data to specific points in the cardiac cycle to minimize image blurring and other motion artifacts.Dogs: 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)Mitral Valve Prolapse: Abnormal protrusion or billowing of one or both of the leaflets of MITRAL VALVE into the LEFT ATRIUM during SYSTOLE. This allows the backflow of blood into left atrium leading to MITRAL VALVE INSUFFICIENCY; SYSTOLIC MURMURS; or CARDIAC ARRHYTHMIA.Aortic Coarctation: A birth defect characterized by the narrowing of the AORTA that can be of varying degree and at any point from the transverse arch to the iliac bifurcation. Aortic coarctation causes arterial HYPERTENSION before the point of narrowing and arterial HYPOTENSION beyond the narrowed portion.Echocardiography, Three-Dimensional: Echocardiography amplified by the addition of depth to the conventional two-dimensional ECHOCARDIOGRAPHY visualizing only the length and width of the heart. Three-dimensional ultrasound imaging was first described in 1961 but its application to echocardiography did not take place until 1974. (Mayo Clin Proc 1993;68:221-40)Hemodynamics: The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.Mitral Valve Insufficiency: Backflow of blood from the LEFT VENTRICLE into the LEFT ATRIUM due to imperfect closure of the MITRAL VALVE. This can lead to mitral valve regurgitation.Heart Auscultation: Act of listening for sounds within the heart.Stroke Volume: 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.Coronary Circulation: The circulation of blood through the CORONARY VESSELS of the HEART.Echocardiography, Doppler, Color: Echocardiography applying the Doppler effect, with the superposition of flow information as colors on a gray scale in a real-time image.Heart Rate: The number of times the HEART VENTRICLES contract per unit of time, usually per minute.Aortic Aneurysm: An abnormal balloon- or sac-like dilatation in the wall of AORTA.Electrocardiography: 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.Atrial Function: The hemodynamic and electrophysiological action of the HEART ATRIA.Heart Sounds: The sounds heard over the cardiac region produced by the functioning of the heart. There are four distinct sounds: the first occurs at the beginning of SYSTOLE and is heard as a "lubb" sound; the second is produced by the closing of the AORTIC VALVE and PULMONARY VALVE and is heard as a "dupp" sound; the third is produced by vibrations of the ventricular walls when suddenly distended by the rush of blood from the HEART ATRIA; and the fourth is produced by atrial contraction and ventricular filling.Aortic Valve: The valve between the left ventricle and the ascending aorta which prevents backflow into the left ventricle.Elasticity: Resistance and recovery from distortion of shape.Pulse: The rhythmical expansion and contraction of an ARTERY produced by waves of pressure caused by the ejection of BLOOD from the left ventricle of the HEART as it contracts.Echocardiography, Doppler, Pulsed: Echocardiography applying the Doppler effect, with velocity detection combined with range discrimination. Short bursts of ultrasound are transmitted at regular intervals and the echoes are demodulated as they return.Ductus Arteriosus: A fetal blood vessel connecting the pulmonary artery with the descending aorta.Ventricular Function, Right: The hemodynamic and electrophysiological action of the right HEART VENTRICLE.Pulsatile Flow: Rhythmic, intermittent propagation of a fluid through a BLOOD VESSEL or piping system, in contrast to constant, smooth propagation, which produces laminar flow.Torsion, Mechanical: A twisting deformation of a solid body about an axis. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Aortography: Radiographic visualization of the aorta and its branches by injection of contrast media, using percutaneous puncture or catheterization procedures.Ventricular Pressure: The pressure within a CARDIAC VENTRICLE. Ventricular pressure waveforms can be measured in the beating heart by catheterization or estimated using imaging techniques (e.g., DOPPLER ECHOCARDIOGRAPHY). The information is useful in evaluating the function of the MYOCARDIUM; CARDIAC VALVES; and PERICARDIUM, particularly with simultaneous measurement of other (e.g., aortic or atrial) pressures.Muscle, Smooth, Vascular: The nonstriated involuntary muscle tissue of blood vessels.Cardiac Catheterization: Procedures in which placement of CARDIAC CATHETERS is performed for therapeutic or diagnostic procedures.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Heart Septum: This structure includes the thin muscular atrial septum between the two HEART ATRIA, and the thick muscular ventricular septum between the two HEART VENTRICLES.Heart Atria: The chambers of the heart, to which the BLOOD returns from the circulation.Stress, Mechanical: A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.Cardiomyopathy, Hypertrophic: A form of CARDIAC MUSCLE disease, characterized by left and/or right ventricular hypertrophy (HYPERTROPHY, LEFT VENTRICULAR; HYPERTROPHY, RIGHT VENTRICULAR), frequent asymmetrical involvement of the HEART SEPTUM, and normal or reduced left ventricular volume. Risk factors include HYPERTENSION; AORTIC STENOSIS; and gene MUTATION; (FAMILIAL HYPERTROPHIC CARDIOMYOPATHY).Fetal Heart: 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.Tricuspid Valve: The valve consisting of three cusps situated between the right atrium and right ventricle of the heart.Aortic Aneurysm, Thoracic: An abnormal balloon- or sac-like dilatation in the wall of the THORACIC AORTA. This proximal descending portion of aorta gives rise to the visceral and the parietal branches above the aortic hiatus at the diaphragm.Myocardium: 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.Cineangiography: Motion pictures of the passage of contrast medium through blood vessels.Myocardial Bridging: A malformation that is characterized by a muscle bridge over a segment of the CORONARY ARTERIES. Systolic contractions of the muscle bridge can lead to narrowing of coronary artery; coronary compression; MYOCARDIAL ISCHEMIA; MYOCARDIAL INFARCTION; and SUDDEN CARDIAC DEATH.Pericardium: 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.Regional Blood Flow: The flow of BLOOD through or around an organ or region of the body.Heart Murmurs: Heart sounds caused by vibrations resulting from the flow of blood through the heart. Heart murmurs can be examined by HEART AUSCULTATION, and analyzed by their intensity (6 grades), duration, timing (systolic, diastolic, or continuous), location, transmission, and quality (musical, vibratory, blowing, etc).Ventricular Dysfunction, Left: 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.Rabbits: 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.Arteriosclerosis: Thickening and loss of elasticity of the walls of ARTERIES of all sizes. There are many forms classified by the types of lesions and arteries involved, such as ATHEROSCLEROSIS with fatty lesions in the ARTERIAL INTIMA of medium and large muscular arteries.Echocardiography, Transesophageal: Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues using a transducer placed in the esophagus.Cardiac Output: 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).Arteries: The vessels carrying blood away from the heart.Pulmonary Artery: The short wide vessel arising from the conus arteriosus of the right ventricle and conveying unaerated blood to the lungs.Aortic Valve Stenosis: A pathological constriction that can occur above (supravalvular stenosis), below (subvalvular stenosis), or at the AORTIC VALVE. It is characterized by restricted outflow from the LEFT VENTRICLE into the AORTA.Coronary Vessels: The veins and arteries of the HEART.Aneurysm, Dissecting: Aneurysm caused by a tear in the TUNICA INTIMA of a blood vessel leading to interstitial HEMORRHAGE, and splitting (dissecting) of the vessel wall, often involving the AORTA. Dissection between the intima and media causes luminal occlusion. Dissection at the media, or between the media and the outer adventitia causes aneurismal dilation.Heart Function Tests: Examinations used to diagnose and treat heart conditions.Image Processing, Computer-Assisted: A technique of inputting two-dimensional images into a computer and then enhancing or analyzing the imagery into a form that is more useful to the human observer.Reproducibility of Results: 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.Observer Variation: The failure by the observer to measure or identify a phenomenon accurately, which results in an error. Sources for this may be due to the observer's missing an abnormality, or to faulty technique resulting in incorrect test measurement, or to misinterpretation of the data. Two varieties are inter-observer variation (the amount observers vary from one another when reporting on the same material) and intra-observer variation (the amount one observer varies between observations when reporting more than once on the same material).Endothelium, Vascular: Single pavement layer of cells which line the luminal surface of the entire vascular system and regulate the transport of macromolecules and blood components.Amyl Nitrite: A vasodilator that is administered by inhalation. It is also used recreationally due to its supposed ability to induce euphoria and act as an aphrodisiac.Blood Vessel Prosthesis Implantation: Surgical insertion of BLOOD VESSEL PROSTHESES to repair injured or diseased blood vessels.Magnetic Resonance Imaging, Cine: A type of imaging technique used primarily in the field of cardiology. By coordinating the fast gradient-echo MRI sequence with retrospective ECG-gating, numerous short time frames evenly spaced in the cardiac cycle are produced. These images are laced together in a cinematic display so that wall motion of the ventricles, valve motion, and blood flow patterns in the heart and great vessels can be visualized.Reference Values: The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.Heart Block: 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.Pulmonary Circulation: The circulation of the BLOOD through the LUNGS.Tomography, X-Ray Computed: Tomography using x-ray transmission and a computer algorithm to reconstruct the image.Heart Diseases: Pathological conditions involving the HEART including its structural and functional abnormalities.Magnetic Resonance Imaging: 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.Papillary Muscles: Conical muscular projections from the walls of the cardiac ventricles, attached to the cusps of the atrioventricular valves by the chordae tendineae.Doppler Effect: Changes in the observed frequency of waves (as sound, light, or radio waves) due to the relative motion of source and observer. The effect was named for the 19th century Austrian physicist Johann Christian Doppler.Heart Valve Prosthesis: A device that substitutes for a heart valve. It may be composed of biological material (BIOPROSTHESIS) and/or synthetic material.Aortic Valve Insufficiency: Pathological condition characterized by the backflow of blood from the ASCENDING AORTA back into the LEFT VENTRICLE, leading to regurgitation. It is caused by diseases of the AORTIC VALVE or its surrounding tissue (aortic root).Tricuspid Valve Insufficiency: Backflow of blood from the RIGHT VENTRICLE into the RIGHT ATRIUM due to imperfect closure of the TRICUSPID VALVE.Ultrasonography, Doppler: Ultrasonography applying the Doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. (Stedman, 25th ed)Hypertension: Persistently high systemic arterial BLOOD PRESSURE. Based on multiple readings (BLOOD PRESSURE DETERMINATION), hypertension is currently defined as when SYSTOLIC PRESSURE is consistently greater than 140 mm Hg or when DIASTOLIC PRESSURE is consistently 90 mm Hg or more.Rheology: The study of the deformation and flow of matter, usually liquids or fluids, and of the plastic flow of solids. The concept covers consistency, dilatancy, liquefaction, resistance to flow, shearing, thixotrophy, and VISCOSITY.Imaging, Three-Dimensional: The process of generating three-dimensional images by electronic, photographic, or other methods. For example, three-dimensional images can be generated by assembling multiple tomographic images with the aid of a computer, while photographic 3-D images (HOLOGRAPHY) can be made by exposing film to the interference pattern created when two laser light sources shine on an object.Endocardium: The innermost layer of the heart, comprised of endothelial cells.Aortic Rupture: The tearing or bursting of the wall along any portion of the AORTA, such as thoracic or abdominal. It may result from the rupture of an aneurysm or it may be due to TRAUMA.Pressure: A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Elasticity Imaging Techniques: Non-invasive imaging methods based on the mechanical response of an object to a vibrational or impulsive force. It is used for determining the viscoelastic properties of tissue, and thereby differentiating soft from hard inclusions in tissue such as microcalcifications, and some cancer lesions. Most techniques use ultrasound to create the images - eliciting the response with an ultrasonic radiation force and/or recording displacements of the tissue by Doppler ultrasonography.Aortic Aneurysm, Abdominal: An abnormal balloon- or sac-like dilatation in the wall of the ABDOMINAL AORTA which gives rise to the visceral, the parietal, and the terminal (iliac) branches below the aortic hiatus at the diaphragm.Blood Vessel Prosthesis: Device constructed of either synthetic or biological material that is used for the repair of injured or diseased blood vessels.Counterpulsation: A technique for assisting the circulation by decreasing the afterload of the left ventricle and augmenting the diastolic pressure. It may be achieved by intra-aortic balloon, or by implanting a special pumping device in the chest, or externally by applying a negative pressure to the lower extremities during cardiac systole.Sheep: Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.Cardiac Pacing, Artificial: Regulation of the rate of contraction of the heart muscles by an artificial pacemaker.Image Interpretation, Computer-Assisted: Methods developed to aid in the interpretation of ultrasound, radiographic images, etc., for diagnosis of disease.Vascular Resistance: The force that opposes the flow of BLOOD through a vascular bed. It is equal to the difference in BLOOD PRESSURE across the vascular bed divided by the CARDIAC OUTPUT.Vasodilation: The physiological widening of BLOOD VESSELS by relaxing the underlying VASCULAR SMOOTH MUSCLE.Vasoconstriction: The physiological narrowing of BLOOD VESSELS by contraction of the VASCULAR SMOOTH MUSCLE.Models, Anatomic: Three-dimensional representation to show anatomic structures. Models may be used in place of intact animals or organisms for teaching, practice, and study.Mitral Valve Stenosis: Narrowing of the passage through the MITRAL VALVE due to FIBROSIS, and CALCINOSIS in the leaflets and chordal areas. This elevates the left atrial pressure which, in turn, raises pulmonary venous and capillary pressure leading to bouts of DYSPNEA and TACHYCARDIA during physical exertion. RHEUMATIC FEVER is its primary cause.Mitral Valve Annuloplasty: A type of heart valve surgery that involves the repair, replacement, or reconstruction of the annulus of the MITRAL VALVE. It includes shortening the circumference of the annulus to improve valve closing capacity and reinforcing the annulus as a step in more complex valve repairs.Ultrasonography, Prenatal: The visualization of tissues during pregnancy through recording of the echoes of ultrasonic waves directed into the body. The procedure may be applied with reference to the mother or the fetus and with reference to organs or the detection of maternal or fetal disease.Phenylephrine: An alpha-1 adrenergic agonist used as a mydriatic, nasal decongestant, and cardiotonic agent.Tetralogy of Fallot: A combination of congenital heart defects consisting of four key features including VENTRICULAR SEPTAL DEFECTS; PULMONARY STENOSIS; RIGHT VENTRICULAR HYPERTROPHY; and a dextro-positioned AORTA. In this condition, blood from both ventricles (oxygen-rich and oxygen-poor) is pumped into the body often causing CYANOSIS.Vasoconstrictor Agents: Drugs used to cause constriction of the blood vessels.Aortitis: Inflammation of the wall of the AORTA.Biomechanical Phenomena: The properties, processes, and behavior of biological systems under the action of mechanical forces.Carotid Arteries: Either of the two principal arteries on both sides of the neck that supply blood to the head and neck; each divides into two branches, the internal carotid artery and the external carotid artery.Cardiomyopathy, Dilated: 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.Aneurysm, Infected: Aneurysm due to growth of microorganisms in the arterial wall, or infection arising within preexisting arteriosclerotic aneurysms.Perfusion: Treatment process involving the injection of fluid into an organ or tissue.Swine: Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).Dobutamine: A catecholamine derivative with specificity for BETA-1 ADRENERGIC RECEPTORS. It is commonly used as a cardiotonic agent after CARDIAC SURGERY and during DOBUTAMINE STRESS ECHOCARDIOGRAPHY.Prospective Studies: 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.Blood Volume: Volume of circulating BLOOD. It is the sum of the PLASMA VOLUME and ERYTHROCYTE VOLUME.Hypertrophy, Left Ventricular: Enlargement of the LEFT VENTRICLE of the heart. This increase in ventricular mass is attributed to sustained abnormal pressure or volume loads and is a contributor to cardiovascular morbidity and mortality.Vasodilator Agents: Drugs used to cause dilation of the blood vessels.Calcium: 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.ElastinDisease Models, Animal: 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.Pulmonary Veins: The veins that return the oxygenated blood from the lungs to the left atrium of the heart.Cardiomegaly: 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.Magnetic Resonance Angiography: Non-invasive method of vascular imaging and determination of internal anatomy without injection of contrast media or radiation exposure. The technique is used especially in CEREBRAL ANGIOGRAPHY as well as for studies of other vascular structures.Feasibility Studies: Studies to determine the advantages or disadvantages, practicability, or capability of accomplishing a projected plan, study, or project.Atherosclerosis: A thickening and loss of elasticity of the walls of ARTERIES that occurs with formation of ATHEROSCLEROTIC PLAQUES within the ARTERIAL INTIMA.Polyethylene Terephthalates: Polyester polymers formed from terephthalic acid or its esters and ethylene glycol. They can be formed into tapes, films or pulled into fibers that are pressed into meshes or woven into fabrics.Rats, Wistar: A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.Myocardial Ischemia: 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).Aging: The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.Image Enhancement: Improvement of the quality of a picture by various techniques, including computer processing, digital filtering, echocardiographic techniques, light and ultrastructural MICROSCOPY, fluorescence spectrometry and microscopy, scintigraphy, and in vitro image processing at the molecular level.Muscle Relaxation: That phase of a muscle twitch during which a muscle returns to a resting position.Muscle Contraction: A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.Contrast Media: Substances used to allow enhanced visualization of tissues.Dilatation, Pathologic: The condition of an anatomical structure's being dilated beyond normal dimensions.Marfan Syndrome: An autosomal dominant disorder of CONNECTIVE TISSUE with abnormal features in the heart, the eye, and the skeleton. Cardiovascular manifestations include MITRAL VALVE PROLAPSE, dilation of the AORTA, and aortic dissection. Other features include lens displacement (ectopia lentis), disproportioned long limbs and enlarged DURA MATER (dural ectasia). Marfan syndrome is associated with mutations in the gene encoding fibrillin, a major element of extracellular microfibrils of connective tissue.Pacemaker, Artificial: A device designed to stimulate, by electric impulses, contraction of the heart muscles. It may be temporary (external) or permanent (internal or internal-external).Predictive Value of Tests: 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.Sensitivity and Specificity: 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)Diet, Atherogenic: A diet that contributes to the development and acceleration of ATHEROGENESIS.Arrhythmias, Cardiac: 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.Acetylcholine: A neurotransmitter found at neuromuscular junctions, autonomic ganglia, parasympathetic effector junctions, a subset of sympathetic effector junctions, and at many sites in the central nervous system.Heart Failure: 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.Ultrasonography: The visualization of deep structures of the body by recording the reflections or echoes of ultrasonic pulses directed into the tissues. Use of ultrasound for imaging or diagnostic purposes employs frequencies ranging from 1.6 to 10 megahertz.Finite Element Analysis: A computer based method of simulating or analyzing the behavior of structures or components.Gestational Age: The age of the conceptus, beginning from the time of FERTILIZATION. In clinical obstetrics, the gestational age is often estimated as the time from the last day of the last MENSTRUATION which is about 2 weeks before OVULATION and fertilization.Signal Processing, Computer-Assisted: Computer-assisted processing of electric, ultrasonic, or electronic signals to interpret function and activity.Venae Cavae: The inferior and superior venae cavae.Coronary Disease: 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.Nitric Oxide: A free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. Nitric oxide is one of the ENDOTHELIUM-DEPENDENT RELAXING FACTORS released by the vascular endothelium and mediates VASODILATION. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic GUANYLATE CYCLASE and thus elevates intracellular levels of CYCLIC GMP.Treatment Outcome: 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.Rats, Inbred WKY: A strain of Rattus norvegicus used as a normotensive control for the spontaneous hypertensive rats (SHR).Heart Conduction System: 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.Cardiomyopathies: 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).Isoproterenol: 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.Rats, Sprague-Dawley: 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.Coronary Stenosis: Narrowing or constriction of a coronary artery.Aneurysm, False: Not an aneurysm but a well-defined collection of blood and CONNECTIVE TISSUE outside the wall of a blood vessel or the heart. It is the containment of a ruptured blood vessel or heart, such as sealing a rupture of the left ventricle. False aneurysm is formed by organized THROMBUS and HEMATOMA in surrounding tissue.Coronary Angiography: Radiography of the vascular system of the heart muscle after injection of a contrast medium.Iliac Artery: Either of two large arteries originating from the abdominal aorta; they supply blood to the pelvis, abdominal wall and legs.Ventricular Remodeling: 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.Cardiotonic Agents: 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).Organ Size: The measurement of an organ in volume, mass, or heaviness.Rats, Inbred SHR: A strain of Rattus norvegicus with elevated blood pressure used as a model for studying hypertension and stroke.Analysis of Variance: A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.Regression Analysis: Procedures for finding the mathematical function which best describes the relationship between a dependent variable and one or more independent variables. In linear regression (see LINEAR MODELS) the relationship is constrained to be a straight line and LEAST-SQUARES ANALYSIS is used to determine the best fit. In logistic regression (see LOGISTIC MODELS) the dependent variable is qualitative rather than continuously variable and LIKELIHOOD FUNCTIONS are used to find the best relationship. In multiple regression, the dependent variable is considered to depend on more than a single independent variable.Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Cholesterol, Dietary: Cholesterol present in food, especially in animal products.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Linear Models: Statistical models in which the value of a parameter for a given value of a factor is assumed to be equal to a + bx, where a and b are constants. The models predict a linear regression.Algorithms: A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.Retrospective Studies: 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.Norepinephrine: Precursor of epinephrine that is secreted by the adrenal medulla and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers and of the diffuse projection system in the brain arising from the locus ceruleus. It is also found in plants and is used pharmacologically as a sympathomimetic.Apolipoproteins E: A class of protein components which can be found in several lipoproteins including HIGH-DENSITY LIPOPROTEINS; VERY-LOW-DENSITY LIPOPROTEINS; and CHYLOMICRONS. Synthesized in most organs, Apo E is important in the global transport of lipids and cholesterol throughout the body. Apo E is also a ligand for LDL receptors (RECEPTORS, LDL) that mediates the binding, internalization, and catabolism of lipoprotein particles in cells. There are several allelic isoforms (such as E2, E3, and E4). Deficiency or defects in Apo E are causes of HYPERLIPOPROTEINEMIA TYPE III.Follow-Up Studies: 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.Anastomosis, Surgical: Surgical union or shunt between ducts, tubes or vessels. It may be end-to-end, end-to-side, side-to-end, or side-to-side.Nitroprusside: A powerful vasodilator used in emergencies to lower blood pressure or to improve cardiac function. It is also an indicator for free sulfhydryl groups in proteins.Myocardial Infarction: NECROSIS of the MYOCARDIUM caused by an obstruction of the blood supply to the heart (CORONARY CIRCULATION).Myocytes, Cardiac: Striated muscle cells found in the heart. They are derived from cardiac myoblasts (MYOBLASTS, CARDIAC).Computer Simulation: Computer-based representation of physical systems and phenomena such as chemical processes.Nitric Oxide Synthase Type III: A CALCIUM-dependent, constitutively-expressed form of nitric oxide synthase found primarily in ENDOTHELIAL CELLS.Endothelium: A layer of epithelium that lines the heart, blood vessels (ENDOTHELIUM, VASCULAR), lymph vessels (ENDOTHELIUM, LYMPHATIC), and the serous cavities of the body.Catheterization: Use or insertion of a tubular device into a duct, blood vessel, hollow organ, or body cavity for injecting or withdrawing fluids for diagnostic or therapeutic purposes. It differs from INTUBATION in that the tube here is used to restore or maintain patency in obstructions.Stents: Devices that provide support for tubular structures that are being anastomosed or for body cavities during skin grafting.Takayasu Arteritis: A chronic inflammatory process that affects the AORTA and its primary branches, such as the brachiocephalic artery (BRACHIOCEPHALIC TRUNK) and CAROTID ARTERIES. It results in progressive arterial stenosis, occlusion, and aneurysm formation. The pulse in the arm is hard to detect. Patients with aortitis syndrome often exhibit retinopathy.Nitric Oxide Synthase: An NADPH-dependent enzyme that catalyzes the conversion of L-ARGININE and OXYGEN to produce CITRULLINE and NITRIC OXIDE.Case-Control Studies: Studies which start with the identification of persons with a disease of interest and a control (comparison, referent) group without the disease. The relationship of an attribute to the disease is examined by comparing diseased and non-diseased persons with regard to the frequency or levels of the attribute in each group.Subclavian Artery: Artery arising from the brachiocephalic trunk on the right side and from the arch of the aorta on the left side. It distributes to the neck, thoracic wall, spinal cord, brain, meninges, and upper limb.Angiotensin II: An octapeptide that is a potent but labile vasoconstrictor. It is produced from angiotensin I after the removal of two amino acids at the C-terminal by ANGIOTENSIN CONVERTING ENZYME. The amino acid in position 5 varies in different species. To block VASOCONSTRICTION and HYPERTENSION effect of angiotensin II, patients are often treated with ACE INHIBITORS or with ANGIOTENSIN II TYPE 1 RECEPTOR BLOCKERS.Constriction: The act of constricting.Potassium Chloride: A white crystal or crystalline powder used in BUFFERS; FERTILIZERS; and EXPLOSIVES. It can be used to replenish ELECTROLYTES and restore WATER-ELECTROLYTE BALANCE in treating HYPOKALEMIA.Coronary Artery Disease: Pathological processes of CORONARY ARTERIES that may derive from a congenital abnormality, atherosclerotic, or non-atherosclerotic cause.
This allows the blood to be ejected from the left ventricle into the aorta during ventricular systole. The amount of blood that ... After ventricular systole, the pressure in the left ventricle decreases as it relaxes and begins to fill up with blood from the ... This causes a leaking of blood from the aorta into the left ventricle. This means that some of the blood that was already ... Under normal conditions, >50% of the blood in a filled left ventricle is ejected into the aorta to be used by the body. ...
There are two valves present, an anterior valve, extending into the anterior aorta seems to prevent backflow of hemolymph, and ... Myofibrils are mostly arranged circularly and constrict the heart during systole. ... The circulatory system consists mainly of a dorsal tubular heart with anterior and posterior aortae. The heart is innervated by ...
During ventricular systole, pressure rises in the left ventricle and when it is greater than the pressure in the aorta, the ... When ventricular systole ends, pressure in the left ventricle rapidly drops and the pressure in the aorta forces aortic valve ... pulmonary veins) → left atrium (atrial appendage) → mitral valve → left ventricle → aortic valve (aortic sinus) → (aorta and ... at the opening between the left ventricle and the aorta Atrioventricular valves[edit]. Main articles: Mitral valve and ...
Aortic rupture - Frank rupture of the aorta is often fatal from internal bleeding. Rupture of the aorta can occur at the sites ... It pulsates opposite to the heart such that it inflates during diastole and relaxes during systole. Deflation during systole ... Dissection of the ascending aorta (type A) is a surgical emergency while dissection of the descending aorta (type B) can ... Coarctation of the aorta (CoA) - Narrowing of the aorta, typically of the aortic arch and is classically found in Turner ...
... is the pressure against which the heart must work to eject blood during systole. In other words, it is the end load ... Due to the increased afterload, the ventricle has to work harder to accomplish its goal of ejecting blood into the aorta. Thus ... In ventricular systole under MR, regurgitant blood flows backwards/retrograde back and forth through a diseased and leaking ... The diastolic blood pressure in the aorta would fall, due to regurgitation. This would result in an increase in pulse pressure ...
An unequal pulse between upper and lower extremities is seen in coarctation to aorta, aortitis, block at bifurcation of aorta, ... Pulsatile This description of the pulse implies the intrinsic physiology of systole and diastole. Scientifically, systole and ... In coarctation of aorta, femoral pulse may be significantly delayed as compared to radial pulse (unless there is coexisting ... This pulse signals a flagging effort of the heart to sustain itself in systole. Pulsus bigeminus: indicates a pair of hoofbeats ...
Atrial systole, also known as auricular systole due to the contraction of the two auricles of the heart, takes approximately ... The role of the left ventricle is to pump newly oxygenated blood to the body through the aorta. Cardiac muscle has automaticity ... The term systole is synonymous with contraction (movement or shortening) of a muscle. Electrical systole is the electrical ... Because the human heart is a four chambered organ, there are atrial systole, atrial diastole, ventricular systole and ...
The walls of aorta are elastic. This elasticity helps to maintain the blood pressure throughout the body. When the aorta ... Back flow of blood through its opening during atrial systole is prevented by the Thebesian valve. The smallest cardiac veins ... The first part of the systemic circulation is the aorta, a massive and thick-walled artery. The aorta arches and gives branches ... It branches from the abdominal aorta and returns blood to the ascending vena cava. It is the blood supply to the kidneys, and ...
... allowing blood to exit the left ventricle into the aorta. When ventricular systole ends, pressure in the left ventricle rapidly ... pulmonary veins) → left atrium (atrial appendage) → mitral valve → left ventricle → aortic valve (aortic sinus) → (aorta and ... The aortic valve is a valve in the human heart between the left ventricle and the aorta. It is one of the two semilunar valves ... When the left ventricle contracts (systole), pressure rises in the right ventricle. When the pressure in the left ventricle ...
In normal individuals, during ventricular systole, the pressure in the ascending aorta and the left ventricle will equalize, ... They may also develop a left atrial thrombus that embolizes, most commonly, to the terminal aorta creating acute pain and rear ... Upon cardiac catheterization, catheters can be placed in the left ventricle and the ascending aorta, to measure the pressure ... Classically, the thromboembolism lodges at the iliac trifurcation of the aorta, occluding either one or both of the common ...
It consists of a cylindrical polyethylene balloon that sits in the aorta, approximately 2 centimeters (0.79 in) from the left ... That is, it actively deflates in systole, increasing forward blood flow by reducing afterload through a vacuum effect. It ... Other possible complications are cerebral embolism during insertion, infection, dissection of the aorta or iliac artery, ... grafts in the aorta Aortic aneurysm Aortofemoral grafts Sepsis Since the device is placed in the femoral artery and aorta it ...
Two coronary arteries originate from the left side of the heart at the beginning (root) of the aorta, just after the aorta ... During contraction of the ventricular myocardium (systole), the subendocardial coronary vessels (the vessels that enter the ... There are three aortic sinuses (dilations) in the wall of the aorta just superior to the aortic semilunar valve. Two of these, ... The following are the named branches of the coronary circulation in a right-dominant heart: Aorta Left coronary artery / Left ...
The walls of large elastic arteries (e.g. aorta, common carotid, subclavian, and pulmonary arteries and their larger branches) ... These arteries distend when the blood pressure rises during systole and recoil when the blood pressure falls during diastole. ... of the arterial blood pressure waveform in terms of the interaction between the stroke volume and the compliance of the aorta ... elastic arteries exceeds that leaving them due to the peripheral resistance there is a net storage of blood during systole ...
Atrial systole lasts approximately 100 ms and ends prior to ventricular systole, as the atrial muscle returns to diastole. ... This allows the blood to be pumped out of the ventricles and into the aorta and pulmonary trunk. The total time elapsed from ... Since ventricular systole began with an EDV of approximately 130 mL of blood, this means that there is still 50-60 mL of blood ... Ventricular systole follows the depolarization of the ventricles and is represented by the QRS complex in the ECG. It may be ...
During ventricular systole, pressure rises in the left ventricle and when it is greater than the pressure in the aorta, the ... When ventricular systole ends, pressure in the left ventricle rapidly drops and the pressure in the aorta forces aortic valve ... at the opening between the left ventricle and the aorta Atrioventricular valvesEdit. Main articles: Mitral valve and Tricuspid ... A septum begins to form between what will later become the ascending aorta and pulmonary tract. As the septum forms, the two ...
During most of the cardiac cycle, ventricular pressure is less than the pressure in the aorta, but during systole, the ... pulmonary veins) → left atrium (atrial appendage) → mitral valve → left ventricle → aortic valve (aortic sinus) → (aorta and ... The left ventricle receives oxygenated blood from the left atrium via the mitral valve and pumps it through the aorta via the ... During systole, the ventricles contract, pumping blood through the body. During diastole, the ventricles relax and fill with ...
It is the loudest in systole, but can often be heard at the beginning and at the end of diastole. It is very dependent on body ... As the left ventricle empties, its pressure falls below the pressure in the aorta. Aortic blood flow quickly reverses back ... It is caused by the closure of the semilunar valves (the aortic valve and pulmonary valve) at the end of ventricular systole ... or systole. When the ventricles begin to contract, so do the papillary muscles in each ventricle. The papillary muscles are ...
During most of the cardiac cycle, ventricular pressure is less than the pressure in the aorta, but during systole, the ... The left ventricle receives oxygenated blood from the left atrium via the mitral valve and pumps it through the aorta via the ... The extra pressure exerted is also needed to stretch the aorta and other arteries to accommodate the increase in blood volume. ... Likewise in the systolic phase, the left ventricle must contract rapidly and forcibly to pump this blood into the aorta, ...
When the LV begins to contract and develop pressure, blood is still entering the LV from the aorta (since aortic pressure is ... causing blood to flow back into the left atrium during ventricular systole. The constant backflow of blood through the leaky ... The increased ventricular stroke volume in this case includes the volume of blood ejected into the aorta as well as the volume ... Once the LV pressure exceeds the aortic diastolic pressure, the LV begins to eject blood into the aorta. The increased end- ...
... the ascending aorta, or the transverse aortic arch. Identifying hemodynamic patterns in the aorta after left ventricle systole ... The size of the proximal aorta should be evaluated carefully during the workup. The initial diameter of the aorta should be ... Blood does not flow centrally through the aorta in BAV, but along the right-anterior and right-posterior vessel wall for RL and ... This is potentially more damaging to the aorta in comparison to the streamline flow and short-lived burst of high velocity at ...
... or the amount of blood ejected from the left ventricle during systole and inversely proportional to the compliance of the aorta ... The aorta has the highest compliance in the arterial system due in part to a relatively greater proportion of elastin fibers ... If the aorta becomes rigid in conditions such as arteriosclerosis or atherosclerosis, the pulse pressure would be very high. ... Nataf P, Lansac E (2006). "Dilation of the thoracic aorta: medical and surgical management". Heart. 92: 1345-52. doi:10.1136/ ...
... usually from aorta to pulmonary artery, with higher flow during systole and lower flow during diastole) cardiomegaly (enlarged ... A PDA allows a portion of the oxygenated blood from the left heart to flow back to the lungs by flowing from the aorta (which ... the blood flow is from the higher-pressure aorta to the now lower-pressure pulmonary arteries. In normal newborns, the DA is ... resulting in irregular transmission of blood between the aorta and the pulmonary artery. PDA is common in newborns with ...
The ventral aorta delivers blood to the gills where it is oxygenated and flows, through the dorsal aorta, into the rest of the ... Afterload, or how much pressure the heart must generate to eject blood at systole, is influenced by vascular resistance. It can ... In tetrapods, the ventral aorta has divided in two; one half forms the ascending aorta, while the other forms the pulmonary ... The semilunar aortic valve is at the base of the aorta and also is not attached to papillary muscles. This too has three cusps ...
For example, Iguana hearts, like the majority of the squamates hearts, are composed of three chambers with two aorta and one ... a muscular ridge that subdivides the ventricle during ventricular diastole and completely divides it during ventricular systole ... Crocodilians have an anatomically four-chambered heart, similar to birds, but also have two systemic aortas and are therefore ... and two aortas that lead to the systemic circulation. The degree of mixing of oxygenated and deoxygenated blood in the three- ...
... systole pumps blood through the aortic valve, the aorta, and all the arteries to provide systemic circulation of oxygenated ... Atrial systole lasts approximately 100 ms and ends prior to ventricular systole, as the atrial muscle returns to diastole. The ... LV systole is volumetrically defined as the left ventricular ejection fraction (LVEF). Similarly, RV systole is defined as the ... left atrial systole is ended and ventricular systole is about to begin. The time variable for the left systolic cycle is ...
Both ventricles do systole together. But the atria do systole before the ventricles. Even though the atrial systole comes ... Aortic valve - blood goes out of the left ventricle to the body (through the aorta) ... The PR-Interval is the space between atrial systole (P) and ventricular systole (QRS). The QT-Interval is from when the QRS ... The ECG shows atrial systole. This is called a P-wave. Then ventricular systole happens. This is called the QRS or QRS-complex ...
For example, Iguana hearts, like the majority of the squamates hearts, are composed of three chambers with two aorta and one ... a muscular ridge that subdivides the ventricle during ventricular diastole and completely divides it during ventricular systole ... Crocodilians have an anatomically four-chambered heart, similar to birds, but also have two systemic aortas and are therefore ... and two aortas that lead to the systemic circulation. The degree of mixing of oxygenated and deoxygenated blood in the three- ...
It is normally less than 10 mm Hg,[26] but may be increased in e.g. coarctation of the aorta.[26] ... displaystyle PI={\frac {v_{systole}-v_{diastole}}{v_{mean}}}}. Relation between blood flow velocity and total cross-section ... Blood being pumped out of the heart first enters the aorta, the largest artery of the body. It then proceeds to divide into ... Blood velocities in arteries are higher during systole than during diastole. One parameter to quantify this difference is the ...
Persistent congenital left to right shunt across the PDA from the aorta to the pulmonary artery *--, continuous murmur in the ... May be appreciated due to the abnormal coaptation of the mitral valve leaflets during ventricular systole ... Characterized by flow that begins in systole & continues through S2 into diastole ... Aortic pressure , pulmonary pressure during both systole & diastole. * ...
When the heart contracts and forces the blood out of the ventricles it is known as systole. When the heart is relaxed and ... The left ventricle pumps oxygenated blood out of the heart and around the body in the aorta. Valves close to stop blood flowing ... Aorta. The major artery taking oxygenated blood from the heart around the body ...
WSS was calculated at this location on maximum systole. MR imaging was accomplished on a 1.5T scanner. Four methods were ... The four methods are equivalent in calculating WSS at the ascending aorta when blood flow velocities have a good parabolic ... Wall shear stress calculation in ascending aorta using phase contrast magnetic resonance imaging. Investigating effective ways ... magnetic resonance imaging were performed in 20 patients at a level perpendicular to the long axis of the ascending aorta ...
A novel parameter "cusp opening angle" (i.e., degree of valve leaflet alignment to the outflow axis in systole) was introduced ... Nathan and coauthors used finite element analysis in order to investigate the wall stress in the proximal aorta of BAV patients ... Relation of Bicuspid Aortic Valve Morphology to the Dilatation Pattern of the Proximal Aorta: Focus on the Transvalvular Flow. ... This strongly suggests that the abnormal systolic flow pattern is not secondarily to a dilated aorta or to aortic valve ...
B) Lowers steadily during ventricle systole. C) The highest when blood is being pumped out of the left ventricle into the aorta ... Aorta[edit]. The aorta is the largest of the arteries in the systemic circuit. The blood is pumped from the left ventricle into ... Aorta: the largest of the arteries in the systemic circuit Aortic Valve: lies between the left ventricle and the aorta ... The aorta is an elastic artery, and as such is able to distend. When the left ventricle contracts to force blood into the aorta ...
monitor chemical composition; found in aorta & carotid arteries. 120-140. Systole; V contract. ... Shunt b/w p. artery & aorta-bypass lungs; becomes ligamentum arteriosum. Another name for the AV valves:. Tricupsid & Bicuspid ... Systole. Ventricles contract (120-140); happens during depolarization; atria during P; ventricles during QRS. ... supplies liver, gallbladder, spleen, stomach, esophagus (abdominal aorta). hepatic artery. celiac branch to liver (abdominal ...
Aortogram obtained with a 6F pigtail catheter showing the ascending aorta, descending aorta, and great vessels. Image courtesy ... Left ventricular systole causes a rapid increase in left ventricular pressure. When it becomes higher than that of the left ... Note the tortuous aorta. Image courtesy of Tak W. Kwan, MD View Media Gallery ... When the left ventricular pressure falls to a level below that of the aorta, the aortic valve closes. As the left ventricular ...
Point C: aortic valve closure, end systole. *Line CD: isovolumic relaxation during LV diastole *Myofibris relax/stretch to ... LV still needs to generate higher pressures to eject blood volume into the aorta than if there were also afterload reduction ... Line AB: isovolumic contraction during LV systole *Myofibrils begin to contract but no ejection occurs ... Line BC: ejection of blood into aorta *Difference in LV volume = stroke volume ...
11) Blood enters aorta and pulmonary 1) All muscles relaxartery VENTRICULAR SYSTOLE GENERAL DIASTOLE (0.3 SEC) (0.4 SEC)10) ... blood is pumped into the aorta and the aorta stretches. The pulse wave passes along the walls of the aorta and into similar ... The stent and deflated balloon is put onto the end of a long tube and inserted into the femoral artery, up the aorta and into ... This is called systole.• When the cardiac muscle relaxes, pressure within the heart decreases. This allows blood to flow into ...
Center image shows aorta with catheter inflated as in diastole. Image on right shows aorta with catheter deflated as in systole ...
This is when the ventricles contract and pump blood into the aorta and pulmonary artery. During systole, the atrioventricular ... The aorta is a big artery that leaves the heart carrying this oxygenated blood. Branches off of the aorta send blood to the ... Like a tree, the branches gets smaller and smaller as they get farther from the aorta.. At each body part, a network of tiny ... During this time, the aortic and pulmonary valves are open to allow blood into the aorta and pulmonary artery. When the ...
This is when the ventricles contract and pump blood into the aorta and pulmonary artery. During systole, the atrioventricular ... The aorta is a big artery that leaves the heart carrying this oxygenated blood. Branches off of the aorta send blood to the ... Like a tree, the branches gets smaller and smaller as they get farther from the aorta.. At each body part, a network of tiny ... During this time, the aortic and pulmonary valves are open to allow blood into the aorta and pulmonary artery. When the ...
Outline of heart showing action of intra-aortic balloon pump during systole. Outline of heart showing action of intra-aortic ... Orientation figure shows location of heart and aorta in body. LifeART Collection Images Copyright © 1989-2001 by Lippincott ...
Both ventricles do systole together. But the atria do systole before the ventricles. Even though the atrial systole comes ... Aortic valve - blood goes out of the left ventricle to the body (through the aorta) ... The PR-Interval is the space between atrial systole (P) and ventricular systole (QRS). The QT-Interval is from when the QRS ... The ECG shows atrial systole. This is called a P-wave. Then ventricular systole happens. This is called the QRS or QRS-complex ...
Guard outfloow of blood from left ventricle out of aorta. Open during systole, closed during diastole ... anterior to the superior vena cava and posterior to the ascending aorta and pulmonary trunk. Important for surgery is it ... Contract before systole and maintain tension throughout in order to prevent backflow. ... Prevents backflow between left atrium and ventricle by closing during systole. Opens during diastole. ...
The second heart sound, S2, occurs with the end of ventricular systole. It is associated with closure of the aortic and ... Its intensity is directly related to the amount of closing pressure in the aorta and pulmonary arteries. ... directly relates to the force of ventricular contraction and the amount of ventricular pressure developed during systole. The ...
The pumping phase of the heart is the systole phase. It begins when the atria, which are the upper chambers of the heart, ... The ventricles contract and push blood through valves into the aorta and the pulmonary artery. The heart relaxes in between ...
3D pressure mapping in a healthy aorta in systole (right) and diastole (left). Note the pressure inversion during diastole. ... 3D blood flow characteristics within the aorta are complex and dependent on the individual geometry and shape of the aorta. ... LV: left ventricle, AAo: ascending aorta, DAo: descending aorta. Taken from [13]. ... The figure shows images from two parts of the cardiac cycle (systole and diastole) reconstructed using full k-space data (top) ...
... aorta ,/li,,/ul,,ul,,li,b) PDA MUST be present to allow blood flow to: ,/li,,/ul,,ul,,li,i) aorta ,/li,,/ul,,ul,,li,ii) ... throughout systole ,/li,,/ul,,ul,,li,LV hypertrophy ,/li,,/ul,www.freelivedoctor.com ... ul,,li,Transposition of the Great Arteries ,/li,,/ul,,ul,,li,(TGA) ,/li,,/ul,,ul,,li,a) aorta arises from RV ,/li,,/ul,,ul,,li, ... ul,,li,Truncus Arteriosus ,/li,,/ul,,ul,,li,Failure of separation into aorta and ,/li,,/ul,,ul,,li,pulmonary artery ,/li,,/ul,, ...
a) Photograph of the aortic valve in open and closed position (from the aorta). (b) Aortic valve histology emphasizing ... d) Schematic depiction of layered aortic valve cuspal structure and configuration of collagen and elastin during systole and ... The large cuspal deformation during the cycle between systole and diastole is facilitated by biomechanical cooperativity ... heart valve endothelial cells are different from those in the aorta.16,17 For example, in response to mechanical stress, ...
... during systole phase while the flap was curved towards the False Lumen (FL) in porcine aorta as seen in (b). (c) Representative ... Significant stiffness of the aged human aorta when compared to porcine aorta or lack of completely developed distal tears could ... was set to 2 L/min for all tested aorta samples. The pump parameters were set constant for each experiment (HR: 72 bpm, Systole ... on FDR for porcine aortae and the effect of demographic (age, gender) and clinical variables (hypertension, systole and ...
Many preparations of the aorta during systole. N engl j med.. sildenafil tablets leaflet *Generico de viagra ...
VENTRICULAR SYSTOLE IS NEXT *FORCES BLOOD INTO EITHER PULMONARY OR AORTA *AT SAME TIME, ATRIA HAVE RETURNED TO DIASTOLE ... SYSTOLE - CLOSE PUL. AND AOTRIC VALVES * SOMETIMES A THIRD SOUND CAN BE HEARD - BLOOD MOVING TO VENT. ... AORTIC - LEFT VENTRICLE AND DESCENDING AORTA. PULMONIC - RIGHT VENT. AND PULMONARY ARTERY. ...
CFD can be used to confirm pulsatile ejection into the main pulmonary artery and the ascending aorta. ... Note also that after TAH implantation there will be no meaningful electrocardiogram waveform to denote systole. Visualization ... and the outflow valve is attached to a short outflow graft that replaces the proximal segment of the aorta or pulmonary artery ... assessment for air bubbles in the atria and pulmonary veins as well as air bubbles exiting the device into the ascending aorta ...
Aortic dissection (10 centimeter [cm] segment of the ascending aorta and the arch of the aorta). The ascending aorta has a 3-cm ... 2004; Creager and Loscalzo 2008; AHA 2010]. Blood expelled from the heart under high pressure (systole) pushes more blood ... Aortic Dissection. The aorta is the major artery that carries blood from the heart to the rest of the body. The aortic wall is ... Coarctation of the aorta Congenital bicuspid or unicuspid aortic valve History of cardiac surgery, particularly aortic valve ...
  • For further details please refer to Bock J, Frydrychowicz A, Lorenz R, Hirtler D, Barker AJ, Johnson KM, Arnold R, Burkhardt H, Hennig J, Markl M. In vivo noninvasive 4D pressure difference mapping in the human aorta: phantom comparison and application in healthy volunteers and patients Magn Reson Med. (uniklinik-freiburg.de)
  • Complete velocity encoding measurements using phase contrast magnetic resonance imaging were performed in 20 patients at a level perpendicular to the long axis of the ascending aorta approximately 2cm above the aortic valve. (nih.gov)
  • At this point, the aortic semilunar valve is forced open, and blood flows into the aorta. (merckmanuals.com)
  • Common causes of aortic regurgitation include vasodilation of the aorta, previous rheumatic fever , infection such as infective endocarditis , degeneration of the aortic valve, and Marfan's syndrome . (wikipedia.org)
  • Common causes of aortic regurgitation include dilation of the aorta, previous rheumatic fever , infection, i.e. infective endocarditis , myxomatous degeneration of the aortic valve, Marfan's syndrome and rupture of a congenitally fenestrated aortic cusp. (wikidoc.org)
  • Bicuspidy of the aortic valve and aneurysmal dilation of the ascending aorta (56 mm in diameter) were noted on TTE. (onlinejacc.org)
  • Aortic insufficiency can be due to abnormalities of either the aortic valve or the aortic root (the beginning of the aorta ). (bionity.com)
  • One of the well known cures for the annuloaortic ectasia is a vascular grafting surgery using a composite graft as an artificial ascending aorta and an artificial valve. (nii.ac.jp)
  • Flow visualization results showed that vortex flow occurred in the Valsalva sinus due to jet flow through the valve leaflets during systole. (nii.ac.jp)
  • 3 The intrinsic links between the BAVs and aortic dilation have given rise to a concept that the BAVs represent a disorder that affects both the aortic valve and the aorta 3 , 6 , 7 and have led some authors to suggest early replacement of the aorta instead of isolated valve replacement in such patients. (pubmedcentralcanada.ca)
  • 20 Using an ex vivo porcine model for spontaneous Type B dissection we reproduce the lumen pressure characteristics with and without distal re-entry tear, evaluate the changes in the dissected vessel geometry and compare against measurements made in aortae of patients with acute Type B dissection. (springer.com)
  • Ventricular pressure continues to increase until it exceeds the blood pressure in the aorta. (merckmanuals.com)
  • 3. Pump according to claim 1, characterized in that the electronic circuit comprises, for the command of the pump (8), a microprocessor (35) receiving a measurement of the time elapsed since the last R wave of the ECG, a digital measurement of the momentary pressure in the aorta at the poin of the sensor (13) and a measurement of the endo-cavitary potential. (freepatentsonline.com)
  • At the aorta (A) the pressure ( systolic ) is approximately 150 mm. (dictionary.com)
  • The usual Newtonian model of blood viscosity and a non- Newtonian blood model are used to study the velocity distributions, wall pressure and wall shear stress in the aorta over the entire cardiac cycle. (alliedacademies.org)
  • This study revealed that, the overall velocity distributions and wall pressure distributions of the aorta for a non-Newtonian fluid model are similar to the same obtained from Newtonian fluid model but the non-Newtonian nature of blood caused a considerable increase in Wall Shear Stress (WSS) value. (alliedacademies.org)
  • The death certificate and autopsy report were completed by the state medical examiner's office On July 8, 2013, a 37-year-old male career fire and listed "aortic dissection due to hypertensive fighter died from a dissected aorta while on duty. (cdc.gov)