A type of impedance plethysmography in which bioelectrical impedance is measured between electrodes positioned around the neck and around the lower thorax. It is used principally to calculate stroke volume and cardiac volume, but it is also related to myocardial contractility, thoracic fluid content, and circulation to the extremities.
The resistance to the flow of either alternating or direct electrical current.
Recording changes in electrical impedance between electrodes placed on opposite sides of a part of the body, as a measure of volume changes in the path of the current. (Stedman, 25th ed)
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).
1,4:3,6-Dianhydro D-glucitol. Chemically inert osmotic diuretic used mainly to treat hydrocephalus; also used in glaucoma.
The region of the thorax that includes the PLEURAL CAVITY and MEDIASTINUM.
Act of listening for sounds within the heart.
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.
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 movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.
The graphic recording of chest wall movement due to cardiac impulses.
Graphic registration of the heart sounds picked up as vibrations and transformed by a piezoelectric crystal microphone into a varying electrical output according to the stresses imposed by the sound waves. The electrical output is amplified by a stethograph amplifier and recorded by a device incorporated into the electrocardiograph or by a multichannel recording machine.
A technique of measuring the dielectric properties of materials, which vary over a range of frequencies depending on the physical properties of the material. The technique involves measuring, over a range of frequencies, ELECTRICAL IMPEDANCE and phase shift of an electric field as it passes through the material.
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.
The number of times the HEART VENTRICLES contract per unit of time, usually per minute.
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.
PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.
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.
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.
Physical activity which is usually regular and done with the intention of improving or maintaining PHYSICAL FITNESS or HEALTH. Contrast with PHYSICAL EXERTION which is concerned largely with the physiologic and metabolic response to energy expenditure.
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.
Methods or programs of physical activities which can be used to promote, maintain, or restore the physical and physiological well-being of an individual.
Abnormally low BLOOD PRESSURE that can result in inadequate blood flow to the brain and other vital organs. Common symptom is DIZZINESS but greater negative impacts on the body occur when there is prolonged depravation of oxygen and nutrients.
The combination of hemodialysis and hemofiltration either simultaneously or sequentially. Convective transport (hemofiltration) may be better for removal of larger molecular weight substances and diffusive transport (hemodialysis) for smaller molecular weight solutes.
Therapy for the insufficient cleansing of the BLOOD by the kidneys based on dialysis and including hemodialysis, PERITONEAL DIALYSIS, and HEMODIAFILTRATION.
The end-stage of CHRONIC RENAL INSUFFICIENCY. It is characterized by the severe irreversible kidney damage (as measured by the level of PROTEINURIA) and the reduction in GLOMERULAR FILTRATION RATE to less than 15 ml per min (Kidney Foundation: Kidney Disease Outcome Quality Initiative, 2002). These patients generally require HEMODIALYSIS or KIDNEY TRANSPLANTATION.
Imaging methods that result in sharp images of objects located on a chosen plane and blurred images located above or below the plane.
Classical loci in ACUPUNCTURE. They are main and collateral channels, regarded as a network of passages, through which vital energy (Qi) circulates and along which acupoints (ACUPUNCTURE POINTS) are distributed. The meridians are a series of 14 lines upon which more than 400 acupoints are located on the body. (The Pinyin Chinese-English Dictionary, p. 359; Dr. Wu Lancheng, Academy of Traditional Chinese Medicine, Beijing)
Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues. The standard approach is transthoracic.
The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.
Ultrasonic recording of the size, motion, and composition of the heart and surrounding tissues using a transducer placed in the esophagus.
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.
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)
Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)
Inflammation of a vein associated with a blood clot (THROMBUS).
Composition of images of EARTH or other planets from data collected during SPACE FLIGHT by remote sensing instruments onboard SPACECRAFT. The satellite sensor systems measure and record absorbed, emitted, or reflected energy across the spectra, as well as global position and time.
Any visible result of a procedure which is caused by the procedure itself and not by the entity being analyzed. Common examples include histological structures introduced by tissue processing, radiographic images of structures that are not naturally present in living tissue, and products of chemical reactions that occur during analysis.
A principle of estimation in which the estimates of a set of parameters in a statistical model are those quantities minimizing the sum of squared differences between the observed values of a dependent variable and the values predicted by the model.
A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.
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.
The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)

Randomised comparison of electrode positions for cardioversion of atrial fibrillation. (1/174)

OBJECTIVE: To compare the relative efficacy of anteroanterior v anteroposterior electrode pad positions for external cardioversion of atrial fibrillation. DESIGN: Prospective randomised trial. SETTING: Tertiary referral cardiology centre in the United Kingdom. PATIENTS: 90 patients undergoing elective cardioversion for atrial fibrillation. INTERVENTIONS: Cardioversion was attempted with self adhesive electrode pads with an area of 106 cm2 placed either in the anteroanterior (AA) or anteroposterior (AP) positions. Initial shock was 100 J which, if unsuccessful, was followed by 200 J, 300 J, and 360 J if required. Peak current and transthoracic impedance were measured. MAIN OUTCOME MEASURES: Cardioversion success rate and energy requirements. RESULTS: Cardioversion was successful in 81% of the patients (73/90). There was no statistically significant difference in the cardioversion success rate (AA 84%, 38/45 patients; AP 78%, 35/45 patients; p = 0.42) or mean (SD) energy requirement for all patients (AA 223 (96.1) J; AP 232 (110) J) or for patients who were successfully cardioverted (AA 197.9 (82.4) J; AP 195.4 (97.2) J; p = 0.9) between the two pad positions. The mean transthoracic impedance (TTI) for the first shock (AA 77.5 (18.4) ohms; AP 73.7 (18.7) ohms; p = 0.34) was not significantly different between the two groups. TTI correlated significantly with body mass index, percentage body fat, and chest AP diameter. There was a progressive decrease in TTI with serial shocks. While aetiology and TTI were the two independent significant predictive factors for energy requirement, duration of atrial fibrillation was the only independent predictor of cardioversion success in a multivariate analysis. CONCLUSIONS: Electrode pad position is not a determinant of cardioversion success rate or energy requirement.  (+info)

Cyclic changes in right ventricular output impedance during mechanical ventilation. (2/174)

In a context such as acute respiratory distress syndrome, where optimum tidal volume and airway pressure levels are debated, the present study was designed to differentiate the right ventricular (RV) consequences of increasing lung volume from those secondary to increasing airway pressure during tidal ventilation. The study was conducted by combined two-dimensional echocardiographic and Doppler studies in 10 patients requiring mechanical ventilation in the controlled mode because of acute respiratory failure. Continuous monitoring of airway pressure on echocardiographic and Doppler recordings provided accurate timing of each cardiac event during the respiratory cycle, with particular attention being paid to end-expiratory and end-inspiratory atrial diameters, RV dimensions, and pulmonary artery and tricuspid flow estimated by the velocity-time integral (PA(VTI) and T(VTI), respectively). At baseline, lung inflation during the inspiratory phase of mechanical ventilation produced a drop in PA(VTI) from 14.3 +/- 2.6 cm at end expiration to 11.3 +/- 2.1 cm at end inspiration. This drop occurred without reduction in right atrial diameter or in RV diastolic dimensions. It was not preceded but was followed by a decrease in T(VTI), thus confirming an increase in RV outflow impedance. Manipulation of tidal volume without changing airway pressure and manipulation of airway pressure without changing tidal volume demonstrated that tidal volume, but not airway pressure, was the main determinant factor of RV afterloading during mechanical ventilation.  (+info)

Three-dimensional endocardial impedance mapping: a new approach for myocardial infarction assessment. (3/174)

Precise identification of infarcted myocardial tissue is of importance in diagnostic and interventional cardiology. A three-dimensional, catheter-based endocardial electromechanical mapping technique was used to assess the ability of local endocardial impedance in delineating the exact location, size, and border of canine myocardial infarction. Electromechanical mapping of the left ventricle was performed in a control group (n = 10) and 4 wk after left anterior descending coronary artery ligation (n = 10). Impedance, bipolar electrogram amplitude, and endocardial local shortening (LS) were quantified. The infarcted area was compared with the corresponding regions in controls, revealing a significant reduction in impedance values [infarcted vs. controls: 168.8 +/- 11. 7 and 240.7 +/- 22.3 Omega, respectively (means +/- SE), P < 0.05] bipolar electrogram amplitude (1.8 +/- 0.2 mV, 4.4 +/- 0.7 mV, P < 0. 05), and LS (-2.36 +/- 1.6%, 11.9 +/- 0.9%, P < 0.05). The accuracy of the impedance maps in delineating the location and extent of the infarcted region was demonstrated by the high correlation with the infarct area (Pearson's correlation coefficient = 0.942) and the accurate identification of the infarct borders in pathology. By accurately defining myocardial infarction and its borders, endocardial impedance mapping may become a clinically useful tool in differentiating healthy from necrotic myocardial tissue.  (+info)

Relations of stroke volume and cardiac output to body composition: the strong heart study. (4/174)

BACKGROUND: Although cardiac output (CO) plays the vital role of delivering nutrients to body tissues, few data are available concerning the relations of stroke volume (SV) and CO to body composition in large population samples. METHODS AND RESULTS: Doppler and 2D echocardiography and bioelectric impedance in 2744 Strong Heart Study participants were used to calculate SV and CO and to relate them to fat-free body mass (FFM), adipose mass, and demographic variables. Both SV and CO were higher in men than women and in overweight than normal-weight individuals, but these differences were diminished or even reversed by normalization for FFM or body surface area. In both sexes, SV and CO were more strongly related to FFM than adipose mass, other body habitus measures, arterial pressure, diabetes, or age. In multivariate analyses using the average of Doppler and left ventricular SV to minimize measurement variability, FFM was the strongest correlate of SV and CO; other independent correlates were adipose mass, systolic pressure, diabetes, age, and use of digoxin and calcium channel and beta-blockers. CONCLUSIONS: In a population-based sample, SV and CO are more strongly related to FFM than other variables; increased FFM may be the primary determinant of increased SV and CO in obesity.  (+info)

Ventricular afterload and ventricular work in fontan circulation: comparison with normal two-ventricle circulation and single-ventricle circulation with blalock-taussig shunts. (5/174)

BACKGROUND: Recent studies have indicated that there are inherent limitations associated with Fontan physiology. However, there have been no quantitative analyses of the effects of right heart bypass on ventricular afterload, hydraulic power, and resultant overall hemodynamics. Methods and Results- During routine cardiac catheterization, aortic impedance and ventricular hydraulic power were determined, both at rest and under increased ventricular work induced by dobutamine, in 17 patients with Fontan circulation, 15 patients with a single ventricle whose pulmonary circulation was maintained only by Blalock-Taussig shunts, and 13 patients who had normal 2-ventricle circulation. Both vascular resistance (nonpulsatile load on the ventricle) and pulsatile components of ventricular afterload (represented by low-frequency impedance) were significantly higher in the Fontan group than in the other groups (P<0.01), and this was associated with decreased cardiac output in the Fontan patients. In addition, hydraulic power cost per unit forward flow was 40% lower in the 2-ventricle circulation than in the single-ventricle circulation, suggesting lower ventricular efficiency in single-ventricle circulation attributable to the lack of a pulmonary ventricle. Furthermore, in the Fontan group, beta-adrenergic reserve was markedly decreased because of a limited preload reserve. CONCLUSIONS: Fontan physiology is associated with disadvantageous ventricular power and afterload profiles and has limited ventricular reserve capacity. Thus, to improve the long-term prognosis of patients after Fontan surgery, future research should be conducted into medical interventions that can overcome these limitations inherent in Fontan circulation.  (+info)

Endocardial and epicardial steroid lead pacing in the neonatal and paediatric age group. (6/174)

AIM: To compare the performance of steroid eluting epicardial and endocardial leads in infants and children requiring permanent pacing. METHODS: Evaluation of pacing and sensing characteristics, impedances, and longevity of 159 steroid eluting leads implanted in 95 children. Group A consisted of 24 children weighing less than 15 kg with 15 endocardial leads (five atrial, 10 ventricular) and 19 epicardial leads (five atrial, 14 ventricular). Group B consisted of 71 children weighing more than 15 kg with 106 endocardial leads (56 atrial, 58 ventricular) and 19 epicardial leads (nine atrial, 10 ventricular). RESULTS: Group A: Stimulation thresholds were lower for ventricular endocardial leads at implant (mean (SD) 0.84 (0.54) v 1.59 (0.64) V, p < 0.014) and at two year follow up (ventricular 0.64 (0.24) v 1.65 (0.69) V, p < 0.003). Impedance and sensing thresholds did not differ significantly at implant and follow up. Group B: Stimulation thresholds were lower for ventricular endocardial leads at implant (0.72 (0.48) v 1.48 (0.58) V, p < 0.001) and at follow up (0.88 (0.46) v 1.55 (0.96) V, p < 0.009). Impedance did not differ. Sensing thresholds were also better for ventricular endocardial leads at follow up (9.1 (5.2) v 14.2 (6.4) mV, p < 0.02). Complications requiring intervention occurred in both groups (n = 7 for endocardial v n = 18 for epicardial leads). CONCLUSIONS: Endocardial and epicardial steroid eluting leads have comparable performance in the paediatric population.  (+info)

Changes in the transthoracic impedance signal predict the outcome of a 70 degrees head-up tilt test. (7/174)

We determined whether early changes in central haemodynamics, as determined by transthoracic impedance, induced by a 70 degrees head-up tilt (HUT) test could predict syncope. Heart rate, arterial blood pressure and central haemodynamics [pre-ejection period and rapid left ventricular ejection time ( T (1)), slow ejection time ( T (2)) and d Z /d t (max) (where Z is thoracic impedance), assessed by the transthoracic impedance technique], were recorded during supine rest and during a 45 min 70 degrees HUT test in 68 patients (40+/-2 years) with a history of unexplained recurrent syncope. We found that 38 patients (42+/-3 years) had a symptomatic outcome to 70 degrees HUT (fainters) and 30 (39+/-2 years) had a negative outcome (non-fainters). When measured between 5 and 10 min of 70 degrees HUT, T (2) had increased significantly only in the fainters, and a change in T (2) of >40 ms from baseline predicted a positive outcome with a sensitivity of 68% and a specificity of 70%. During supine rest prior to 70 degrees HUT, the fainters exhibited a shorter T (2) than non-fainters (183+/-10 compared with 233+/-14 ms; P <0.01), and a T (2) of <199 ms predicted a positive outcome to 70 degrees HUT with a sensitivity of 68% and a specificity of 63%. Incorporation of the changes that occurred from rest to 70 degrees HUT in other haemodynamic variables (heart rate >11 beats/min, systolic pressure <2 mmHg, diastolic pressure <7 mmHg and pulse pressure <-3 mmHg) increased the specificity to 97% and the positive predictive value to 93%. Thus transthoracic impedance could detect differences in central haemodynamics between fainters and non-fainters during supine rest and during the initial period of 70 degrees HUT with a consistent sensitivity and specificity when combined with peripheral haemodynamic variables.  (+info)

Respiratory sinus arrhythmia during speech production. (8/174)

The amplitude of the respiratory sinus arrhythmia (RSA) was investigated during a reading aloud task to determine whether alterations in respiratory control during speech production affect the amplitude of RSA. Changes in RSA amplitude associated with speech were evaluated by comparing RSA amplitudes during reading aloud with those obtained during rest breathing. A third condition, silent reading, was included to control for potentially confounding effects of cardiovascular responses to cognitive processes involved in the process of reading. Calibrated respiratory kinematics, electrocardiograms (ECGs), and speech audio signals were recorded from 18 adults (9 men, 9 women) during 5-min trials of each condition. The results indicated that the increases in respiratory duration, lung volume, and inspiratory velocity associated with reading aloud were accompanied by similar increases in the amplitude of RSA. This finding provides support for the premise that sensorimotor pathways mediating metabolic respiration are actively modulated during speech production.  (+info)

Synonyms for Impedance cardiography in Free Thesaurus. Antonyms for Impedance cardiography. 1 synonym for cardiography: electrocardiography. What are synonyms for Impedance cardiography?
Impedance cardiography (ICG) is a noninvasive technology measuring total electrical conductivity of the thorax and its changes in time to process continuously a number of cardiodynamic parameters, such as Stroke Volume, SV, Heart Rate, HR, Cardiac Output, CO, Ventricular Ejection Time, VET, Pre-ejection Period and used to detect the impedance changes caused by a high-frequency, low magnitude current flowing through the thorax between additional two pairs of electrodes located outside of the measured segment. The sensing electrodes also detect the ECG signal, which is used as a timing clock of the system. Impedance cardiography (ICG), also referred to as electrical impedance plethysmography (EIP) or Thoracic Electrical Bioimpedance (TEB) has been researched since the 1940s. NASA helped develop the technology in the 1960s. The use of impedance cardiography in psychophysiological research was pioneered by the publication of an article by Miller and Horvath in 1978. Subsequently, the recommendations ...
This BSL PRO lesson describes hardware and software setup of the BSL System to record ECG, Impedance (Z0), and Derivative Impedance (dZ/dt), and measure relative differences in Cardiac Output and Stroke Volume using a noninvasive bioimpedance technique.. The Lesson Procedure for BSL 4.0.1 or above includes an extensively updated physiological introduction that covers Cardiac Output as a Function of Stroke Volume and Heart Rate, Cardiac Output as Related to Mean Arterial Pressure and Peripheral Resistance, How to Determine Cardiac Output, Principles of Impedance Cardiography (ICG), and Ideas for eliciting cardiovascular responses through physical maneuvers and psychological tasks.. Suggested reading: Methodological Guidelines for Impedance Cardiography ...
The pathogenic processes responsible for cardiovascular disease have their origins in childhood. Although childrens measures of heart rate and blood pressure have been found to be reliable, the reliability of impedance cardiography derived measures have not been evaluated. Thirty-three children, ages 8-11 participated in two sessions. Stressors included serial subtraction, isometric handgrip, and mirror-image tracing. Results indicated the impedance measures showed moderately high temporal stability (average scores r(avg) = 74; difference scores r(avg) = .53) and intertask consistency (average scores r(avg) = .78; difference scores r(avg) = .53). Blood pressure demonstrated the lowest reliability; Heather index, preejection period, and stroke volume demonstrated the highest. These findings suggest childrens cardiovascular reactivity to laboratory stressors can be reliably and consistently assessed using impedance cardiography.
TY - JOUR. T1 - Systolic time ratio by impedance cardiography to distinguish preserved vs impaired left ventricular systolic function in heart failure. AU - Thompson, Brenda. AU - Drazner, Mark H.. AU - Dries, Daniel L.. AU - Yancy, Clyde W.. PY - 2008/12/1. Y1 - 2008/12/1. N2 - Left ventricular ejection fraction (EF) is used to assess patients with heart failure (HF); however, frequent measurements are not cost-effective. Impedance cardiography (ICG) is a low-cost, noninvasive test that measures systolic time intervals and may be a method for detecting impaired vs intact EF. This study evaluated the relationship between EF by echocardiography or gated nuclear ventriculography and systolic time ratio (STR) by ICG in outpatients with chronic HF. A retrospective chart review identified 52 patients with EF and STR measured within 2 weeks. There was an inverse correlation between STR and EF (r=)0.54; P,.001). The area under the receiver operating characteristic curve for STR to identify reduced EF ...
Introduction Electric velocimetry (EV) is normally a kind of impedance cardiography, and it is a non-invasive and applicable approach to cardiac result monitoring continuously. acquired a bias/MPE of 39.00%/46.27%. Bias/MPE for EVMM was 8.07%/37.26% where in fact the OTX and NEURO subgroups were within the number of H0, however the PREM and SEPSIS subgroups were beyond your range. Mechanical venting, noninvasive constant positive airway pressure venting, body weight, and supplementary stomach closure had been elements that affected evaluation of the techniques significantly. Conclusions This scholarly research implies that EV can be compared with aortic flow-based TTE for pediatric sufferers. Launch TC-DAPK6 supplier In the 1960s, impedance cardiography originated to monitor cardiac result (CO) [1]. This technique is dependant on a big change in level of resistance through the cardiac routine to a transcutaneously used electric AC Rabbit polyclonal to BMPR2 voltage, and can be used to calculate ...
Impedance cardiography (ICG) allows to measure parameters of heart mechanical function. ICG is sensitivity to movement artifacts inter alia breathing, which distorts impedance signal. Several methods were proposed to eliminate this distortion, but they cannot be used to continuous measurement or do not remove movement artifact. Adaptive filter is event-related, it learns signal characteristic within the cycle and removes components uncorrelated with the event. In this study, we compared ICG signal obtained during normal breathing with that after adaptive filtration and ICG signal obtained during momentary breath holding with this signal processed with adaptive filter. We conclude that adaptive filtering may help extract information from noisy and distorted ICG signal, but on the other hand, it may obscure some real changes in signal, for instance, rapid cyclic changes connected with respiration.
Repeatability of Impedance Cardiography Hemodynamic Variables During Treadmill Exercise Purpose To analyze the day to day repeatability of cardiac hemodynamic measurements using a Physio Flow 07 Enduro during treadmill submaximal exercise. Methods 21 male subject ages 18 and older were studied. Two graded treadmill exercise tests consisting of two 5-minute steady state stages (Moderate and Vigorous intensity) were performed using the PhysioFlow device at least 48 hours apart. Cardiac hemodynamic measurements were compared between stages and trials using repeated measures ANOVA, intraclass correlations, and Bland-Altman plots. Results Oxygen consumption (VO2) and respiratory exchange ratio (RER), were not different between the two trials for either Moderate or Vigorous intensities. There was a main effect for intensity for all variables with the exception early diastolic filling ratio (EDFR) and ejection fraction (EF%). Intraclass correlation coefficients between exercise trials were | 0.7 for all
Introduction. The American Heart Association Resuscitation Guidelines advocate four pad positions to achieve defibrillation success following cardiac arrest. Transthoracic impedance (TTI) reflects the electrode-skin interface and patient impedance and affects current amplitude, energy delivered and defibrillation efficacy. Modern defibrillators utilise an impedance compensated waveform to account for changes in TTI to improve defibrillation success. However the effect of electrode pad position and patient characteristics on TTI remains unclear.. Objective. To evaluate the effect of patient characteristics and pad position on Transthoracic impedance (TTI).. Methods. Patients undergoing diagnostic cardiac catheterisation were recruited for the study following regional ethical approval. Standard self-adhesive defibrillator electrodes were applied to patients in both the anterolateral and anteroposterior positions and connected to Heartsine Samaritan defibrillators. TTI was measured by applying a ...
Assessment of stroke volume (SV) is often necessary in clinical and research settings. The clinically established method for SV assessment in pregnancy is echocardiography, but given its limitations, it is not always an appropriate measurement tool. Thoracic impedance cardiography (ICG) allows continuous, non-invasive SV assessment. However, SV determination relies on assumptions regarding the thoracic shape that may mean the algorithm is not valid in pregnancy. The available data regarding the validity of ICG against an established reference standard using modern SV algorithms are both limited and conflicting. We aimed to test the validity of ICG in a clinically realistic setting in late pregnancy using echocardiography. Twenty-nine women in late pregnancy underwent standard echocardiography assessments with simultaneous ICG measurement. Agreement between devices was tested using Bland-Altman analysis. Bland-Altman analysis of the relationship between ICG and echocardiography demonstrated that the 95%
Transthoracic electrical impedance (or admittance) cardiography is a simple technique for the non-invasive and continuous monitoring of stroke volume or cardiac output by detecting the electrical impedance of a thorax which is roughly assumed to be a
On traite des signaux dimp dance thoracique (22, 23) et d ECG (25a, 25b) afin dam liorer la r solution et la pr cision. Were treated thoracic impedance signals (22, 23) and ECG (25a, 25b) to improve the resolution and accuracy. Le traitement adaptatif (26, 28) des signaux ECG consiste num riser, filtrer, diff rencier et lever le diff rentiel obtenu une puissance sup rieure un afin de faire appara tre des changements dans la pente. The adaptive processing (26, 28) of ECG signals is to scan, filter, differentiate and raise the differential obtained a higher power to show a change in the slope. On analyse (30) des blocs des donn es trait s afin didentifier lamplitude maximum et afin de comparer l cart entre des amplitudes maximum afin didentifier de mani re plus pr cise des maximum dondes R. On d termine le d bit systolique partir dun signal dimp dance thoracique ainsi que sa d riv e temporelle. Analyzing (30) blocks of data processed to identify the maximum amplitude and to compare the
Impedance cardiography seems to be a very good, although underappreciated diagnostic method. What may distinguish it from among the many research methods is the fact that it enables non-invasive monitoring of cardiac output, stroke volume and systemic vascular resistance. Holter recording of the hemodynamic parameters makes it possible to study them not only in stationary (hospital, outpatient clinic) conditions, but also during household or professional activities, e.g., during road vehicle driving. Assessment of the trends of changes in the circulatory system of the employee at work makes it possible to judge whether the type of work performed by the worker is well tolerated - whether it is not too hard or too stressful. This is important, therefore, impedance cardiography can be extensively used in occupational medicine. Provision of preventive care to workers according to current standards requires, on the one hand, the use of the latest diagnostic methods while, on the other hand, the ...
BACKGROUND: Recurrent intradialytic hypotension still is a major source of discomfort in hemodialysis patients today, its origin being subject to extensive research. Different hypotheses have been raised to unravel this problem, without forming one c
A system and method for assessing pulmonary performance through transthoracic impedance monitoring is described. Transthoracic impedance measures are directly collected through an implantable medical device. The transthoracic impedance measures are correlated to pulmonary functional measures relative to performance of at least one respiration cycle. The transthoracic impedance measures are grouped into at least one measures set corresponding to one of an inspiratory phase and an expiratory phase. The at least one transthoracic impedance measures set are evaluated to identify a respiratory pattern relative to the inspiratory phase or the expiratory phase to represent pulmonary performance.
OBJECTIVES--To evaluate dependence of posture and exercise on the degree of mitral regurgitation using combined first pass and equilibrium radionuclide cardiography. DESIGN--24 patients with clinically stable chronic mitral regurgitation and sinus rhythm were studied by first pass list mode and simultaneous multigated frame mode equilibrium radionuclide cardiography using red cells labelled with technetium-99m. RESULTS--When patients changed posture from supine to sitting upright, left ventricular volumes decreased considerably. Regurgitation tended to increase in patients with valve prolapse but decreased in patients with ischaemic heart disease and dilated cardiomyopathy. During submaximal bicycle exercise cardiac output increased without dilatation of the left ventricle. The increase in left ventricular forward stroke volume was more pronounced than that in the total stroke volume, leading to a considerable decrease in the regurgitant flow through the mitral valve. The repeatability and ...
Implantable cardioverter defibrillator (ICD) devices with or without cardiac resynchronization therapy (CRT-D) have the ability to continuously monitor heart rate variability, daily heart rate, and patient activity. Changes in these measures have been associated with heart failure prognosis. In addition, ICD or CRT-D devices also have the ability to measure daily intrathoracic impedance. Previous data have demonstrated that device-based intrathoracic impedance measurements correlate with pulmonary capillary wedge pressure and fluid retention, both of which are common measures of heart failure status. The objective of this study is to evaluate whether the heart rate variability, daily heart rate, and/or intrathoracic impedance can be used in conjunction with other methods to determine if patients are ready for hospital discharge. This will be the first step in potentially developing an inpatient care strategy which includes implantable device data. It is hypothesized that device diagnostic data ...
Background: Patients, providers, and health systems are focused on reducing readmissions for patients with acute decompensated heart failure (ADHF). Readmission after hospitalization is common and often secondary to HF decompensation, but it remains challenging to identify patients at-risk. Bioimpedance is a validated marker of thoracic fluid accumulation. We examined whether transthoracic bioimpedance, measured using a Fluid Accumulation Vest (FAV), predicted HF decompensation in advance of a clinical event in patients discharged after ADHF.. Methods: Participants included 42 patients hospitalized for ADHF. Participants were trained on the use of a FAV-smartphone dyad to obtain and transmit a 5-minute bioimpedance measurement once daily for 45-days after discharge. Readmission and diuretic dosing adjustments were identified using participant report and causes adjudicated using medical records. Daily bioimpedance was analyzed using the HF detection strategy shown in Figure. Receiver operating ...
An apparatus comprises an implantable impedance sensing circuit configured to sense an atrial impedance signal when coupled to a plurality of implantable electrodes, and an impedance signal analyzer circuit configured to detect a sudden change in a characteristic of the sensed atrial impedance signal that indicates atrial tachyarrhythmia. The impedance signal analyzer circuit classifies the atrial tachyarrhythmia indication as ST when the detected sudden change satisfies an ST threshold value of the characteristic, classifies the atrial tachyarrhythmia indication as AT when the detected sudden change satisfies an AT threshold value of the characteristic that is different from the ST threshold value, classifies the atrial tachyarrhythmia indication as AF when the detected sudden change satisfies an AF threshold value of the characteristic that is different from the ST and AT amplitude threshold values, and provides a classification of the tachyarrhythmia to a user or process.
BIOPACSs noninvasive cardiac output sensor noninvasively records the parameters associated with Cardiac Output measurements and is ideal for use in Biopac Student Lab Lesson H21, Impedance Cardiography. The sensor incorporates a precision high frequency current source, which injects a small (400 µA rms @ 100 kHz sine wave) current through the measurement tissue volume defined by the placement of a set of current source electrodes. A separate set of monitoring electrodes then measures the voltage developed across the tissue volume. Because the current is constant, the voltage measured is proportional to the characteristics of the biological impedance of the tissue volume. The sensor can be used to measure changes in Cardiac Output under a variety of conditions: laying down, sitting up, standing up, and post-exercise. ...
The performance of impedance cardiography (TEBco), using the BoMed NCCOM3-R7S, and thermodilution (TDco) were compared in eight patients during major abdominal surgery. An opioid, volatile and relaxant anaesthetic technique was employed. This was supplemented with an epidural in five cases. Sets of three cardiac output readings, for both methods, were made at 10-20 min intervals throughout surgery. Data were compared using the Bland and Altman method, regression analysis and a nested model to measure variance components at different stages of surgery. Data from 157 sets of readings are presented. Agreement between the two devices was poor, with a ratio of TDco/TEBco of 115% and limits of agreement of 51-193%. The regression line was TDco=(0.98)×TEBco-0.95 with r=0.60. A more detailed analysis, using nested data, showed good repeatability with coefficients of variation of 5.4% for TDco and 4.8% for TEBco. During surgery shifts in the bias between the two devices occurred, which were related to changes
Cardiodynamic and hemodynamic reactions to emotion-eliciting film sequences were investigated. Thirty-two healthy subjects (12 women, 20 men) were randomly assigned to one of two groups. In the first group, anger was induced using selected scenes of the film Ragtime. In the second group, scenes of the film The Shining were chosen to elicit fear. A documentary film was used as a baseline stimulus in both groups. EKG, impedance cardiography, and blood pressure were continuously monitored. The two emotional conditions elicited significant differential changes in subjective ratings and cardiovascular indices. Fear was associated with decreased cardiac output, increased total peripheral resistance, and a reduction in stroke volume and myocardial contractility. Anger was associated with an increase of cardiac output and small changes in total peripheral resistance. These results support the hypothesis that discrete emotions such as fear and anger elicit differential patterns of physiological ...
A comparison of acoustic cardiography and echocardiography for optimizing pacemaker settings in cardiac resynchronization therapy
TY - JOUR. T1 - Cardiovascular data acquisition in a dynamic motion environment. AU - Mallows, Richard J.. AU - Newman, David G.. PY - 2008/4/1. Y1 - 2008/4/1. N2 - Introduction: One of the challenges in physiological research is the acquisition of good quality, reliable data, especially in the real-world environment. Motor sports provide a unique and challenging environment in which to test the operation and utility of equipment used for physiological data acquisition. Impedance cardiography (IC) is a non-invasive technique for determining stroke volume (SV) and cardiac output (Q̇). The aim of this feasibility study was to determine if IC could be used to acquire reliable, good quality cardiovascular data in a dynamic motion environment such as in a racing car. This summary overviews the use of a mobile physiological testing apparatus in dynamic real world setting. As reviewed, many physiological indicators have been assessed in the motor racing setting. However cardiovascular outputs ...
A Tool to Improve Post-Operative Surgical Outcomes and Reduce Hospital Costs Non-invasive System to Assist in Fluid Management Technology Debuts at the 2011 American Society of Anesthesiologists Conference (ASA) October 15-17th, Booth #2242 BOTHELL, WA - October 13, 2011 - SonoSite, Inc. (Nasdaq:SONO), the world leader and specialist in bedside and point-of-care ultrasound, today introduced the new BioZ® Cardio Profile system with impedance cardiography (ICG) technology for non-invasively monitoring a patients hemodynamic profile in the hospital. Pioneered by NASA in the 1960s, ICG hemodynamic monitoring has traditionally been used to treat patients with heart failure and hypertension, and it is now ready to play a significant role in the anesthesia suite.
Heart the heart rate, nausea, vomiting, dizziness, restlessness, tremors, disorientation, weakness, twitching of eyelids, and lacrimation, which may limit effort or willingness to enter the mediastinum to blend with the lower limb buds develop from the cisterna chyli. In these patients, thus secondarily helping to improve the nutritional health risk behaviors such as impedance cardiography, which can result even with a biomechanical model of the myocardium, kidney, and heart. Kidney, choen jj disorders of sodium homeostasis can usually be rapidly achieved even in the entire health care system is in the. Unlike such things as committee meetings, patient care, argumentativeness, failure to capture. Dallas american heart association circulation, , losek jd, endom e, dietrich a, et al. Relief by post-isometric relaxation, risk factors for clavicular fracture in combination as the experimental group do not report a return for pain. The british school of medicine, st ed. Arteries two structural ...
Must and More offers echo cardiograph test at best and cheap cost. Impedance, electro, vector acoustic, nuclear, ultrasound cardiography are available. Call @ 9582300300
Family Care Clinic - Service Provider of 2D Echo Cardiography, Colour Doppler & Ultrasound Scan & ECG Machine from Nagpur, Maharashtra, India
Timings, Address, Fee And Complete Details Of PMDC Verified Cardiologists For Echo Cardiography In Pakistan. Book Appointment Or Consult Online. Phone: 042-32...
An implantable cardiac device and method monitors a patients body impedance so as to diagnose medical problems, such as fluid balance problems in congestive heart failure patients. The device monitors the patients position and determines an appropriate time for collecting body impedance data when the patient is in repose. The device then obtains a series of measurements of thoracic impedance by transmitting a signal on at least one lead, which may be a standard pacemaker lead, and sensing a signal received at a different point. The series of measurements are combined to obtain desired representations of thoracic impedance. In an embodiment, impedance is represented by an extracellular water (ECW) resistance value and an intracellular water (ICW) resistance value determined using a Cole calculation method.
Heart Failure (HF) is one of the most frequent diagnoses upon hospitalization and is a major cause of death. Cardiac resynchronization therapy (CRT) using an implantable device for synchronous bi-ventricular stimulation leads to improvement of hemodynamic parameters, physical capacity and quality of life. A continuous measurement of the left-ventricular volume would provide information about heart performance and could be used for both heart failure monitoring and optimization of CRT-therapy ...
Methods 43 patients (mean age 57 ± 15 years, LVEF 33 ± 14%) undertook ICD or CRT-D implantation with feature of intrathoracic impedance monitoring system (Medtronic Inc, Minneapolis, MN, US) in our single centre from Sep 2010 to Oct 2012. All patients required in-office follow-up regularly and routinely in month 3, 6, 12 and every 12 months after that. Once alert events occurred and reported, unscheduled follow-up arranged. History taking, device interrogation, NT-proBNP measurement and echocardiogram were collected during each clinic interview. Worsening HF was defined as hospitalisation or presentation of symptoms or signs of HF.. ...
Echocardiography, often referred to as a cardiac echo or simply an echo, is a sonogram of the heart. Echocardiography uses standard M-mode, two-dimensional, three-dimensional, and Doppler ultrasound to create images of the heart. The downstream demand of echocardiography is rigidity. Echocardiography can be generally used for hospital, both public and private hospitals etc. In 2015, […]. Continue Reading ...
The cardiac rehabilitation program at Baroda Heart Institute & Research Centre offers each cardiac patient the opportunity to achieve optimal levels of the health and fitness through an integrated program of exercise and education.
The cardiac rehabilitation program at Baroda Heart Institute & Research Centre offers each cardiac patient the opportunity to achieve optimal levels of the health and fitness through an integrated program of exercise and education.
We use advanced Echo-cardiographs for monitoring heart-conditions of our patients & treat them to make their cardiac muscles function well.
Because blood flow variations are not plethysmographic, this kind of variation gives errors in the measurement of blood volume. Another issue is that of the accuracy of the SV and estimation of other haemodynamic parameters. In particular, using oversimplified models of the torso and cardiovascular systems can negatively influence the accuracy of the estimation. 6 Sketch of the possible frequency domain harmonic spectrum of the EBI signal, which consists of the cardiac and respiratory components (Krivošei 2009). Collegium Antropologicum 33(3), 791-797 (2009). gov/pubmed/19860105. : A mathematical model for fundamental regulation processes in the cardiovascular system. J. Math. Biol. 31(6), 611-631 (1993). 1007 /BF00161201. : Modeling the dynamics of the cardiovascular-respiratory system (CVRS) in humans, a survey. Math. Model. Nat. Phenom. 7(5), 65-77 (2012). 1 051/mmnp/20127506. : Physiological correlates of the cardiac thoracic impedance waveform. Am. Heart J. : Computer simulation in the ...
A multiple monopolar system and method for measuring stroke volume of a patients heart. An intracardiac impedance catheter is provided with a plurality of monopolar electrodes axially spaced along the surface of its distal end, and is used in conjunction with a distant reference electrode which may, for example, be incorporated into the conductive case of a pacemaker. The proximal end of the catheter is attached to the pacemaker, which, in addition to pulse generator circuitry and circuitry for sensing electrical activity of the heart and for controlling pacing rate, includes a constant-current source for current injection into the volume of blood in the patients ventricle and an impedance processor for measuring the resultant voltage between one of the monopolar electrodes in the ventricle and the pacemaker case and for calculating stroke volume therefrom. A system and method are also disclosed for generating a three-phase relationship between cardiac output and heart rate for an individual patient
The mechanical activation of the heart (dZ/dt) will always be preceded by the electrical activation of the heart identified by the QRS complex of the ECG signal. Rather than identifying landmarks on the dZ/dt waveform cycle by cycle in the IMP Analysis application, only the R peak on the ECG series is identified. Using this R peak as an anchor, a section of data from both ECG and dZ/dt is extracted. These extracted portions are averaged over the course of the segment of time being analyzed, producing an average representation of the relationship between ECG and dZ/dt for that segment. Essentially, the ensemble average is produced by lining up all of the identified R peaks on top of each other and then averaging the overlapping signals.. Note: Only good (non-artifact) R peaks are used to build the ensemble average. This ensures that only quality representations of cardiac cycles are included.. The amount of data extracted surrounding each R peak is chosen on the IMP Calibration Settings tab on ...
This technology has been developed by specialist research into a whole host of parameters that are used to monitor CPR effectiveness in real time - things such as End-Tidal CO2, Cardiac Output, Carotid Flow and Impedance Cardiogram. These are the things an advanced life saver with all the right gear would normally do - however it has all been correlated into this simple device for the lay rescuer. It simply tells you to push harder or push faster, or that you are doing good compressions. And it is specific, in real-time, to the victim. So it will advise the correct compressions for a big victim, just as it will do so for a smaller victim. (Please note, this CPR advisor technology automatically is disabled when the paediatric pad-pak is used ie for children 1 to 8 yrs, or up to 25kg). ...
COMMENT ----------------------------------------------------------------------------- Simple synaptic mechanism derived for first order kinetics of binding of transmitter to postsynaptic receptors. A. Destexhe & Z. Mainen, The Salk Institute, March 12, 1993. ----------------------------------------------------------------------------- During the arrival of the presynaptic spike (detected by threshold crossing), it is assumed that there is a brief pulse (duration=Cdur) of neurotransmitter C in the synaptic cleft (the maximal concentration of C is Cmax). Then, C is assumed to bind to a receptor Rc according to the following first-order kinetic scheme: Rc + C ---(Alpha)--, Ro (1) ,--(Beta)--- where Rc and Ro are respectively the closed and open form of the postsynaptic receptor, Alpha and Beta are the forward and backward rate constants. If R represents the fraction of open gates Ro, then one can write the following kinetic equation: dR/dt = Alpha * C * (1-R) - Beta * R (2) and the postsynaptic ...
System and method for beamforming in soft-field tomography | Patient signal sensing device | Systems, methods, and apparatus for neuro-robotic goal selection | Respiration-gated cardiography | Signal analysis related to treatment sites |
We use cookies to ensure that we give you the best experience on our website. If you click Continue well assume that you are happy to receive all cookies and you wont see this message again. Click Find out more for information on how to change your cookie settings ...
7. Chronicity of HF must be substantiated by: 1) documented clinical history of chronic HF and 2) investigational evidence of left ventricular systolic dysfunction (e.g. by echocardiography, ventriculography or nuclear cardiography) within the last 12 months. A current assessment (e.g. echocardiographic) can be performed if this information is not available from the medical history at the time of screening. NB: Left ventricular ejection fraction should be ≤45% or the equivalent rating of at least moderately impaired left ventricular systolic ...
quantium Medical Cardiac Output (qCO) uses impedance cardiography in a simple, continuous, and non-invasive way to estimate the Cardiac output (CO) and other hemodynamic parameters such as the Stroke Volume (SV) and Cardiac index (CI). The CO estimated by the qCO monitor is referred to as the qCO. The impedance plethysmography allows determining changes in volume of the body tissues based on the measurement of the electric impedance at the body surface. The assessment of Cardiac Output (CO) is important because it reveals the main cardiac function: the supply of blood to tissues. CO reflects the hemodynamic flow and hence the transport of oxygen; its clinical applications by non-invasive continuous hemodynamic monitoring are especially useful for some medical specialties like anaesthesiology, emergency care and cardiology, for example to prevent hypoperfusion and to guide fluid administration. Several authors advocate the high reliability and good correlation of cardiography impedance compared ...
The principal finding of this study is that transthoracic ventricular defibrillation with 120-J rectilinear biphasic shocks is more efficacious than that with 200-J damped sine wave monophasic shocks, particularly in patients with a high transthoracic impedance. In addition, successful defibrillation with biphasic shocks could be achieved with nearly 60% less current than that delivered with monophasic shocks.. Although most currently available defibrillators use an energy-calibrated method for defibrillation, transthoracic current appears to be a more precise electrical descriptor of defibrillation threshold (19,22). Defibrillation using an energy-calibrated method may be suboptimal because, for a given energy, current is dependent on transthoracic impedance (Table 1). Therefore, insufficient current may be delivered to patients with high impedance (decreased efficacy), and excessive current may be delivered to patients with low transthoracic impedance (increased toxicity). Manifestations of ...
The effects of 2 fixed antihypertensive combination drugs on blood pressure and aortic elastic properties were compared in 2 parallel groups. Twenty-six patients for 6 months received a calcium antagonist plus ACE inhibitor (verapamil SR 180 mg/trandolapril 1 mg (Vera/Tran)) and 25 patients a beta-adrenoceptor antagonist plus diuretic (metoprolol 100 mg/hydrochlorothiazide 12.5 mg (Meto/HCTZ)). In addition to blood pressure (SBP, DBP), carotidofemoral pulse wave velocity (PWV) was assessed non-invasively. Total peripheral resistance (TPR) was determined from cardiac output derived by electrical impedance cardiography. Sitting DBP decreased for -14.4 mmHg following Vera/Tran compared with -9.2 mmHg following Meto/HCTZ (p = 0.02 for difference between treatments). Blood pressure was normalized (i.e. DBP | 90 mmHg) in 69% of patients with Vera/Tran and in 52% with Meto/HCTZ. PWV was lowered with Vera/Tran to a higher extent than with Meto/HCTZ (differences between group means -0.46 to -0.98 m/sec,
Jones DE, Hollingsworth K, Fattakhova G, MacGowan G, Taylor R, Blamire A, Newton JL. Impaired cardiovascular function in primary biliary cirrhosis. Am J Physiol Gastrointest Liver Physiol 298: G764-G773, 2010. First published February 4, 2010; doi:10.1152/ajpgi.00501.2009.-Cardiovascular system dysregulation in the form of autonomic dysfunction is common at all stages of the disease process in the autoimmune liver disease primary biliary cirrhosis (PBC) and associates with the symptom of fatigue. The mechanisms underpinning autonomic dysfunction in PBC are, however, at present unclear. In this study we set out to explore, for the first time, cardiac structure and function in PBC using impedance cardiography (ICG) and magnetic resonance methodologies. ICG was assessed beat to beat in response to orthostasis (by head-up tilt) in age and sex case-matched high-fatigue and low-fatigue PBC groups (assessed by Fatigue Impact Scale), normal control subjects (n = 15 each group) and a liver disease ...
TY - JOUR. T1 - Capnography accurately detects apnea during monitored anesthesia care. AU - Soto, Roy G.. AU - Fu, Eugene S.. AU - Vila, Hector. AU - Miguel, Rafael V.. PY - 2004/8. Y1 - 2004/8. N2 - Apnea and airway obstruction are common during monitored anesthesia care (MAC). Because their early detection is essential, we sought to measure the efficacy of capnography as an indicator of apnea during MAC at a variety of oxygen flow rates compared with thoracic impedance. Anesthesia care providers using standard American Society of Anesthesiologists monitors were blinded to capnography and thoracic impedance monitoring. Ten (26%) of the 39 patients studied developed 20 s of apnea; none was detected by the anesthesia provider, but all were detected by capnography and impedance monitoring. There was no difference in detection rates between the two methods. Higher oxygen flow rates decreased the amplitude of the capnograph but did not interfere with apnea detection. This pilot study revealed that ...
Introduction: Heart failure (HF) is often associated with hospitalizations due to pulmonary congestion resulting in cardiogenic lung edema (LE). Implant-based monitoring of intrathoracic impedance as a surrogate measure of thoracic fluid status provides the chance to detect early stages of cardiac decompensation. Previously pulmonary fluid congestion has been related to clinical or preload parameters. In this study we tested for the first time the correlation between changes in intrathoracic impedance (Z) and directly measured intrathoracic fluids during LE induction as well as LE recovery.. Methods: 20 anesthetized sheep were studied, 3 served as controls, in 17 acute pulmonary fluid overload was induced by hypervolemia in combination with gradually increasing peripheral arterial resistance, in 5 sheep restitution of pulmonary fluid overload was attempted. Hemodynamics were continuously monitored including LVEDP. A transpulmonary thermodilution system was used to determine intrathoracic blood ...
Stroke is amongthe leading causes of death worldwide and requires immediate care to prevent death or permanent disability. Unfortunately, the current stateof stroke diagnosis is limited to fixed neuroimaging facilities that do not allow rapid stroke diagnosis. Hence, a portable stroke-diagnosis device could assist in the pre-hospital triage of patients. Moreover, such a portable device could also be useful for bedside stroke monitoring of patients in the Neuro Intensive Care Unit (Neuro-ICU) to avoid unnecessary neuroimaging. Recent animal studies and numerical simulations have supported the idea of implementing Electrical Bioimpedance (EBI) in a portable device, allowing non-invasive assessment as a useful tool for the pre-hospital triage of stroke and Traumatic Brain Injury (TBI) patients. Unfortunately, these studies have not reported any results from human subjects in the acute phase of the stroke. The numerical simulations are also based on simple models that sometimes lack necessary ...
0047] The exemplary waveforms 100 have a far shorter wavelength (e.g., 100 microseconds from beginning to end of a pulse) than some conventionally injected signals (e.g., 30 milliseconds for conventional) and are not only charge balanced but also voltage balanced to have a net-zero voltage and a net-zero charge. It is important to note that the net-zero voltage feature, also referred to as the voltage-balanced feature, refers to the voltage formed on blocking capacitors that appear in series with the load. The flow of current through these capacitors builds up voltage across them, Since these capacitors, such as capacitor 628 in FIG. 6, also appear in circuits that are responsible for sensing cardiac activity, it is important that the net voltage built up on them be zero. As a result of the net-zero voltage feature, the influence of an exemplary waveform 100 on sensing cardiac activity will be minimal, Thus, a current with a waveform such as that presented in FIGS. 16 and 19, generates a voltage ...
Update and Perspectives in Critical Care -- Cardiac resynchronisation therapy -- Acute renal failure in the critically ill patient -- Research tool for the study of therapeutic intervention in acute respiratory failure -- Supportive measures to bridge the gap before transplantation in liver failure -- Multiple organ dysfunction after liver transplantation: a role for the quality of functional recovery of the newly grafted liver? -- Homeostasis and acid-base regulation -- Scoring system reinterpretation in critical care -- Paediatric anaesthesia in developing countries: 12 years experience in Bangladesh -- Acute head injury -- The subtle marker called age -- Non invasive cardiovascular monitoring: focus on LIDCO -- Thoracic impedance -- Transpulmonary thermodilution: analysis of beat by beat, peak pressure and stroke volume variations: GEDV, ITBV, EVLW -- Blood-volume measurement methods and evaluation of hepatic function with hydroxyethyl starch and indocyanine green -- Monitoring at the ...
Computed tomographic perfusion imaging detects major perfusion deficits in the middle cerebral artery territory. Because CTP is broadly available, it may play a role in acute stroke management. Arch Neurol. 2000;57:1161-1166
Shivam Diagnostics Centre is a leading diagnostic centres located in Delhi, India that provides number of medical diagnosctic services such as Open MRI, Spiral Ct Scan, Digital Mammography, Color Doppler, 3D/4D/5D Ultra Sound, Echo Cardiography, Stress Echo, Dobutamine Stress Echo, Computerised Lab, Heart Checkup, Digital OPG, Digital X-RAY, Barium Studies, TMT, PFT, H.S.G, I.V.P, E.E.G, EMG, NCV, VEP, BERA etc.
1- Underused. We take the risk of bringing the patient to the cath lab to get answers to questions and then we dont take the time to do the most thorough exam we can. If a patient has intermediate lesion, I think they should all be FFRd. In the last decade, FFR is one of the few (if only) diagnostic/interventions we do for elective CAD that actually shows benefit (FAME2) over medical therapy.. 2- Mandatory is a strong word, but I do think we need to pull the FFR wire out more in elective PCI without non-invasive testing. A very short 90% LCx lesion may very well be FFR negative. The vessel and lesion characteristics should be taken into account. If we want to rid ourselves of the oculo-stenotic reflex in intervention, then we have to investigate lesions more thoroughly.. 3- Just like a hemodynamic assessment and a sat run during a RHC can vary by operator, so too can FFR. Referring providers know which cath docs to send a RHC to and I think that FFR is the same way.. 4- Without a doubt. ...
இதென்ன புது நோயாக இருக்கு வந்தவர் தனது கையில் இருந்த ரிப்போட்டை என்னிடம் நீட்டினார். இருதய நோய் மருத்துவ நிபுணருக்கு கொடுத்த கடிதத்திற்கு பதிலாக அவர் கொடுத்திருந்த சிட்டை அது. வழமையாக உயர் இரத்த அழுத்தத்திற்கு மருந்துகள் சாப்பிட்டு வருகிறார். அண்மையில் செய்த ஈசிஜி பரிசோதனையில் சில மாற்றங்கள் தெரிந்ததால் இருதய நோய் மருத்துவ நிபுணரிடம் அனுப்ப நேர்ந்தது. ECHO Cardiogram உட்பட
Juice up definition, the natural fluid, fluid content, or liquid part that can be extracted from a plant or one of its parts, especially of a fruit: orange juice. See more.
|b|Heli|/b||br| Väljundvõimsus: (8 ohm, 20 Hz - 20 kHz, 0.08% 2-kanaliga): 100W|br| Väljundvõimsus (6 ohm, 1 kHz, 0.7% 2ch Drive): 140W|br| Väljundvõimsus (6 ohm, 1 kHz, 1% 1-kanaliga): 180W|br| FMS RDS Tüüner|br| DTS HD Master|br| DTS:X|br| DTS
The Impedance Cardiography (ICG or Ztot) signal represents the changes of the thoracic impedance due to variations in the blood ... Woltjer, H.H.; Bogaard, H.J.; de Vries, J.M. (1997). "The technique of impedance cardiography". Eur. Heart J. 18 (9): 1396-1403 ... quantium Medical Cardiac Output (qCO) uses impedance cardiography in a simple, continuous, and non-invasive way to estimate the ... Several authors advocate the high reliability and good correlation of cardiography impedance compared to others techniques more ...
1981). "A comparison of cardiac output as simultaneously measured by indicator dilution and impedance cardiography in normal ... The non-invasive bioelectrical impedance technology is a low-cost high technology system designed by Judy as a solution to high ... Already in 1981, Judy did a study showing that the transthoracic electrical impedance method for measuring cardiac output in ... Judy was introduced to the bioelectrical impedance method as a noninvasive means of measuring stroke volume and cardiac output ...
... where blood flow velocity was compared to total body cardiac output as determined by impedance cardiography. Two rhesus ...
... including ongoing projects with impedance cardiography and atrial fibrillation. Honors And Awards,. Henderson R.P. and Webster ... He first proposed the idea of electrical impedance tomography as a medical imaging technique in a publication in 1978. In his ... Webster, J. G. (ed.), Electrical impedance tomography, Adam Hilger, Bristol, England, 1990. Webster, J. G. (ed.), Teaching ... J.G. (1978) "An Impedance Camera for Spatially Specific Measurements of the Thorax". IEEE Trans. Biomed. Eng. 25: 250-254.. ...
... recorded via impedance cardiography. These measures are beneficial because they provide accurate and perceiver-independent ...
... may refer to ICG Communications Illinois Central Gulf Railroad Impedance cardiography, a hemorheology technique for ...
Impedance cardiography K S Rabbani; M Sarker; M H R Akond; T Akter (1999). "Focused Impedance Measurement (FIM): A New ... FIM can be considered a bridge between Four Electrode Impedance Measurement (FEIM) and Electrical impedance Tomography (EIT), ... Identifying zones with specific impedances can provide greater certainty regarding the factors behind the impedance. ... "Thorax mapping for localized lung impedance change using focused impedance measurement (FIM): A pilot study". Electrical ...
Impedance cardiography. *Photoplethysmograph. *Windkessel effect. Notes and references[edit]. *^ a b Tortora, Gerard J.; ...
Once the catheter is in and all preparations are complete elsewhere in the lab, the EP study begins. The two large magnets are brought in on either side of the patient. They are large and looming and will sandwich the patient, but are able to precisely control the position of the electrodes that are on the end of the catheters. The X-ray machine will give the doctor a view of the heart and the position of the electrodes, and the magnets will allow the doctor to guide the electrodes through the heart. The magnets are controlled with either a joystick or game controller. The electrophysiologist begins by moving the electrodes along the conduction pathways and along the inner walls of the heart, measuring the electrical activity along the way. The next step is pacing the heart, this means he/she will speed up or slow down the heart by placing the electrode at certain points along the conductive pathways of the heart and control the depolarization rate of the heart. The doctor will pace each chamber ...
One of the first mentions of the possibility of heart transplantation was by American medical researcher Simon Flexner, who declared in a reading of his paper on "Tendencies in Pathology" in the University of Chicago in 1907 that it would be possible in the then-future for diseased human organs substitution for healthy ones by surgery - including arteries, stomach, kidneys and heart.[4] Not having a human donor heart available, James D. Hardy of the University of Mississippi Medical Center transplanted the heart of a chimpanzee into the chest of a dying Boyd Rush in the early morning of Jan. 24, 1964. Hardy used a defibrillator to shock the heart to restart beating. This heart did beat in Rush's chest for 60 to 90 minutes (sources differ), and then Rush died without regaining consciousness.[5][6][7] Although Hardy was a respected surgeon who had performed the world's first human-to-human lung transplant a year earlier,[8][9] author Donald McRae states that Hardy could feel the "icy disdain" from ...
In 1923 Dr. Elliott Cutler of the Peter Bent Brigham Hospital performed the world's first successful heart valve surgery - a mitral valve repair. The patient was a 12-year-old girl with rheumatic mitral stenosis.. The development of the heart-lung machine in the 1950s paved the way for replacement of the mitral valve with an artificial valve in the 1960s. For decades after, mitral valve replacement was the only surgical option for patients with a severely diseased mitral valve. However, there are some significant downsides to a prosthetic mitral valve. Infection of the valve can occur, which is dangerous and difficult to treat. Patients with mechanical heart valves are required to take blood thinners for the rest of their lives, which presents a risk of bleeding complications. The artificial mitral valve has an elevated risk of stroke. Patients with mechanical heart valves who use warfarin for anticoagulation have to be on long-term anticoagulation therapy. This means they must go to the clinic ...
The Mustard procedure was largely replaced in the late 1980s by the Jatene procedure (arterial switch), in which the native arteries were switched back to normal flow, so that the RV (right ventricle) would be connected to the pulmonary artery and the LV (left ventricle) would be connected to the aorta. This surgery had not been possible prior to 1975 because of difficulty with re-implanting coronary arteries which perfuse the actual heart muscle itself (myocardium), and even after it was first performed the excellent results from the Mustard operation meant that it was a long time before the Jatene procedure took over. ...
Impedance-pH monitoring. *Esophageal pH monitoring. *Esophageal motility study. Stomach. *Bariatric surgery *Adjustable gastric ...
The size of the recorder differs depending on the manufacturer of the device. The average dimensions of today's Holter monitors are about 110x70x30 mm but some are only 61x46x20 mm and weigh 99 g. [6] Most of the devices operate with two AA batteries. In case the batteries are depleted, some Holters allow their replacement even during monitoring. Most of the Holters monitor the ECG via only two or three channels (Note: depending on manufacturer, different counts of leads and lead systems are used). Today's trend is to minimize the number of leads to ensure the patient's comfort during recording. Although two/three channel recording has been used for a long time in the Holter monitoring history, as mentioned above, 12 channel Holters have recently appeared. These systems use the classic Mason-Likar lead system, i.e. producing a signal in the same format as during the common rest ECG and/or stress test measurement. These Holters can occasionally provide information similar to that of a ECG stress ...
Open heart surgery is a procedure in which the patient's heart is opened and surgery is performed on the internal structures of the heart. It was discovered by Wilfred G. Bigelow of the University of Toronto that the repair of intracardiac pathologies was better done with a bloodless and motionless environment, which means that the heart should be stopped and drained of blood. The first successful intracardiac correction of a congenital heart defect using hypothermia was performed by C. Walton Lillehei and F. John Lewis at the University of Minnesota on September 2, 1952. The following year, Soviet surgeon Aleksandr Aleksandrovich Vishnevskiy conducted the first cardiac surgery under local anesthesia.. Surgeons realized the limitations of hypothermia - complex intracardiac repairs take more time and the patient needs blood flow to the body, particularly to the brain. The patient needs the function of the heart and lungs provided by an artificial method, hence the term cardiopulmonary bypass. ...
Radiofrequency energy is used in heart tissue or normal parts to destroy abnormal electrical pathways that are contributing to a cardiac arrhythmia. It is used in recurrent atrial flutter (Afl), atrial fibrillation (AF), supraventricular tachycardia (SVT), atrial tachycardia, Multifocal Atrial Tachycardia (MAT) and some types of ventricular arrhythmia. The energy-emitting probe (electrode) is at the tip of a catheter which is placed into the heart, usually through a vein. This catheter is called the ablator. The practitioner first "maps" an area of the heart to locate the abnormal electrical activity (electrophysiology study) before the responsible tissue is eliminated. Ablation is now the standard treatment for SVT and typical atrial flutter and the technique can also be used in AF, either to block the atrioventricular node after implantation of a pacemaker or to block conduction within the left atrium, especially around the pulmonary veins. In some conditions, especially forms of intra-nodal ...
The majority of atrial septostomies are performed on infants with d-TGA or other cyanotic heart defects. In these cases, a balloon catheter is guided through a large vein into the right atrium, during cardiac catheterization. The catheter is threaded into the foramen ovale, a naturally existing hole between the atria that normally closes shortly after birth. The balloon at the end of the catheter is inflated so as to enlarge the foramen ovale enough that it will no longer become sealed. This allows more oxygenated blood to enter the right heart (especially in the case of d-TGA) where it can be pumped to the rest of the body. The balloon is deflated and the catheter is removed. Sometimes the initial surgery is not entirely successful, or there are other factors that make a simple balloon atrial septostomy impossible, such as an older patient whose foramen ovale has already closed. This is when a blade atrial septostomy is performed. The details of the procedure are largely the same, except that a ...
The ballistocardiograph (BCG) is a measure of ballistic forces on the heart.[1] Ballistocardiography is a technique for producing a graphical representation of repetitive motions of the human body arising from the sudden ejection of blood into the great vessels with each heart beat.[2] It is a vital sign in the 1-20 Hz frequency range which is caused by the mechanical movement of the heart and can be recorded by noninvasive methods from the surface of the body. It was shown for the first time, after an extensive research work by Dr. Isaac Starr, that the effect of main heart malfunctions can be identified by observing and analyzing the BCG signal.[3] Recent work also validates BCG could be monitored using camera in a non-contact manner[4]. One example of the use of a BCG is a ballistocardiographic scale, which measures the recoil of the persons body who is on the scale. A BCG scale is able to show a persons heart rate as well as their weight. The term ballistocardiograph originated from the ...
Impedance threshold device. *Slow code. *Lazarus syndrome, spontaneous autoresuscitation where attempts at artificial ...
The etymology of the word is derived from the Greek electro, because it is related to electrical activity, kardia, Greek for heart, and graph, a Greek root meaning "to write". Alexander Muirhead is reported to have attached wires to a feverish patient's wrist to obtain a record of the patient's heartbeat in 1872 at St Bartholomew's Hospital.[41] Another early pioneer was Augustus Waller, of St Mary's Hospital in London.[42] His electrocardiograph machine consisted of a Lippmann capillary electrometer fixed to a projector. The trace from the heartbeat was projected onto a photographic plate that was itself fixed to a toy train. This allowed a heartbeat to be recorded in real time. An initial breakthrough came when Willem Einthoven, working in Leiden, the Netherlands, used the string galvanometer (the first practical electrocardiograph) he invented in 1901.[43] This device was much more sensitive than both the capillary electrometer Waller used and the string galvanometer that had been invented ...
... is a palliative surgical procedure performed for patients with Tricuspid atresia. It is also part of the surgical treatment path for hypoplastic left heart syndrome. [1][2][3] This procedure has been largely replaced by Bidirectional Glenn procedure. It connects the superior vena cava to the right pulmonary artery.[4] ...
Partial Anomalous Pulmonary Venous Drainage by CMR. CMR examinations in children typically last 15 to 60 minutes. In order to avoid blurry images the child must remain very still during the examination. Different institutions have different protocols for pediatric CMR, but most children 7 years of age and older can cooperate sufficiently for a good quality examination. Providing an age-appropriate explanation of the procedure to the child in advance will increase the likelihood of a successful study. After proper safety screening, parents can be allowed into the MRI scanner room to help their child complete the examination. Some centers allow children to listen to music or watch movies through a specialized MRI-compatible audiovisual system to reduce anxiety and improve cooperation. However, the presence of a calm, encouraging, supportive parent generally produces better results in terms of pediatric cooperation than any distraction or entertainment strategy short of sedation. If the child ...
The original procedure was named for Alfred Blalock, surgeon, Baltimore (1899-1964), Helen B. Taussig, cardiologist, Baltimore/Boston (1898-1986) and Vivien Thomas (1910-1985) who was at that time Blalock's laboratory technician. They all helped to develop the procedure. Taussig, who treated hundreds of infants and children with this disorder, had observed that children with a cyanotic heart defect and a patent ductus arteriosus (PDA) lived longer than those without the PDA. It therefore seemed to her that a shunt which mimicked the function of a PDA might relieve the tetralogy patients' poor oxygenation. In 1943, having broached the possibility of a surgical solution to Robert Gross of Boston without success, Taussig approached Blalock and Thomas in their Hopkins laboratory in 1943. According to the account of the original consultation between the three provided in Vivien Thomas' 1985 autobiography Partners of the Heart, Taussig carefully described the anomaly of Tetralogy of Fallot, but made ...
Impedance: A test to measure lead integrity. Large and/or sudden increases in impedance can be indicative of a lead fracture ... while large and/or sudden decreases in impedance can signify a breach in lead insulation. ...
The use of cold for pain relief and as an anti-inflammatory has been known since the time of Hippocrates (460-377 B.C).[11] Since then there have been numerous accounts of ice used for pain relief including from the Ancient Egyptians and Avicenna of Persia (AD 982-1070).[12] Since 1899, Dr. Campbell White used refrigerants for treating a variety of conditions, including: lupus erythematosus, herpes zoster, chancroid, naevi, warts, varicose leg ulcers, carbuncles, carcinomas and epitheliomas. De Quervain successfully used of carbonic snow to treat bladder papillomas and bladder cancers in 1917. Dr Irving S Cooper, in 1913, progressed the field of cryotherapy by designing a liquid nitrogen probe capable of achieving temperatures of -196 °C, and utilizing it to treat of Parkinson's disease and previously inoperable cancer. Cooper's cryoprobe advanced the practice of cryotherapy, which led to growing interest and practice of cryotherapy. In 1964, Dr. Cahan successfully used his liquid nitrogen ...
Various antiarrhythmic agents can be used to return the heart to normal sinus rhythm. Pharmacological cardioversion is an especially good option in patients with fibrillation of recent onset. Drugs that are effective at maintaining normal rhythm after electric cardioversion can also be used for pharmacological cardioversion. Drugs like amiodarone, diltiazem, verapamil and metoprolol are frequently given before cardioversion to decrease the heart rate, stabilize the patient and increase the chance that cardioversion is successful. There are various classes of agents that are most effective for pharmacological cardioversion. Class I agents are sodium (Na) channel blockers (which slow conduction by blocking the Na+ channel) and are divided into 3 subclasses a, b and c. Class Ia slows phase 0 depolarization in the ventricles and increases the absolute refractory period. Procainamide, quinidine and disopyramide are Class Ia agents. Class 1b drugs lengthen phase 3 repolarization. They include ...
The Rastelli procedure is an open heart surgical procedure developed by Italian physician and cardiac surgery researcher, Giancarlo Rastelli in 1967 at the Mayo Clinic and involves using a pulmonary or aortic homograft conduit to relieve pulmonary obstruction in double outlet right ventricle with pulmonary stenosis. It is used to correct certain combinations of congenital heart defects (CHDs): ...
TECAB surgery uses the da Vinci tele-robotic Stereoscopic 3-D Imaging system. The system consists of a robotic "slave" system at the bedside. The robot relays its information to an external surgical control unit, where a cardiac surgeon has a three-dimensional view of the chest cavity, and twin controllers for the robotic arms. The procedure frequently involves grafting of the internal mammary artery to the diseased coronary artery, and therefore does not require external harvesting of blood vessels.[2] ...
Commissurotomy of heart valves is called valvulotomy, valvotomy,[1] valvuloplasty, or valvoplasty and consists of making one or more incisions at the edges of the commissure formed between the two or three valve leaflets, which relieves the constriction of valvular stenosis (especially mitral valve stenosis). As with many other kinds of surgery, valvular commissurotomy may be done by either open or minimally invasive approaches, and sometimes (but not invariably) the terms surgery and surgical are understood to refer only to the open types, with the minimally invasive types then being referred to as interventional procedures. The minimally invasive approach is through the lumen of a vessel with a catheter, which is why it is often called a transluminal or transcatheter approach. Such approaches begin with a small skin incision to access a vessel that will lead to the heart, making them percutaneous approaches, and they use balloons whose inflation moves the valve leaflets. Thus, altogether, they ...
അഥവാ ഉള്ളടക്കം മറയ്ക്കാൻ നിർദേശിക്കുന്ന മറ്റേതെങ്കിലും പട്ടികകൾ ഉൾപ്പെടുത്തിയിട്ടുണ്ടെങ്കിൽ ഉള്ളടക്കം ...
... recorded via impedance cardiography. These measures are beneficial because they provide accurate and perceiver-independent ...
Learn impedance cardiography techniques.. *Measure the change in cardiovascular responses-Stroke Volume (SV), Cardiac Output ( ... Suggested reading: Methodological Guidelines for Impedance Cardiography , PSYCHOPHYSIOLOGY, Vol. 27, No. 1. ... Principles of Impedance Cardiography (ICG), and Ideas for eliciting cardiovascular responses through physical maneuvers and ... This BSL PRO lesson describes hardware and software setup of the BSL System to record ECG, Impedance (Z0), and Derivative ...
Cardiography, Impedance*. Female. Hemodynamics. Humans. Hypotension / etiology*, physiopathology. Kidney Failure, Chronic / ... resistance were investigated in 68 patients on chronic intermittent hemodialysis utilizing bioelectrical impedance cardiography ...
... cardiography is a simple technique for the non-invasive and continuous monitoring of stroke volume or cardiac output by ... detecting the electrical impedance of a thorax which is roughly assumed to be a ... Cardiography, Impedance / methods*. Electrodes. Finite Element Analysis. Heart / physiology*. Humans. Models, Cardiovascular*. ... Transthoracic electrical impedance (or admittance) cardiography is a simple technique for the non-invasive and continuous ...
Thoracic impedance cardiography (ICG) allows continuous, non-invasive SV assessment. However, SV determination relies on ... Validation of thoracic impedance cardiography by echocardiography in healthy late pregnancy. *Jordan PR McIntyre. 1,2. , ... Impedance Cardiography. Broken lines indicate mean ± 1.96 SD. HR, SV and CO are in beats per minute, mL, and L.min−1, ... Thoracic impedance cardiography (ICG) may overcome some of the disadvantages of the other methods. ICG is a method of non- ...
Antonyms for Impedance cardiography. 1 synonym for cardiography: electrocardiography. What are synonyms for Impedance ... Cybulski, "Ambulatory impedance cardiography," in Ambulatory Impedance Cardiography.. Simultaneous Recording of ICG and ECG ... One of such methods could be impedance cardiography (ICG).. Comparison of non-invasive methods--impedance cardiography and 2- ... Impedance cardiography synonyms, Impedance cardiography antonyms - FreeThesaurus.com https://www.freethesaurus.com/Impedance+ ...
... the reliability of impedance cardiography derived measures have not been evaluated. Thirty-three children, ages 8-11 ... Results indicated the impedance measures showed moderately high temporal stability (average scores r(avg) = 74; difference ... cardiovascular reactivity to laboratory stressors can be reliably and consistently assessed using impedance cardiography. ... OBrien, William H. and McGrath, Jennifer J., "Pediatric Impedance Cardiography: Temporal Stability and Intertask Consistency ...
ICG is sensitivity to movement artifacts inter alia breathing, which distorts impedance signal. Several methods were proposed ... Impedance cardiography (ICG) allows to measure parameters of heart mechanical function. ... Impedance cardiography (ICG) allows to measure parameters of heart mechanical function. ICG is sensitivity to movement ... Adaptive Filter Removes Variability Caused by Respiration from Impedance Cardiography Signal. Marek Żyliński , Małgorzata ...
Keywords: PhysioFlow, Impedance Cardiography, hemodynamic variables, cardiac output, stroke volume, non-invasive ... Repeatability of Impedance Cardiography Hemodynamic Variables During Treadmill Exercise Purpose To analyze the day to day ... Repeatability of Impedance Cardiography Hemodynamic Variables During Treadmill Exercise Purpose To analyze the day to day ... Repeatability of Impedance Cardiography in the Measurement of Cardiovascular Hemodynamics During Exercise ...
Launch TC-DAPK6 supplier In the 1960s, impedance cardiography originated to monitor cardiac result (CO) [1]. This technique is ... Introduction Electric velocimetry (EV) is normally a kind of impedance cardiography,. by Ross Marshall ... Introduction Electric velocimetry (EV) is normally a kind of impedance cardiography, and it is a non-invasive and applicable ... After several adjustments towards the algorithm [1-5], impedance cardiography (thats, electric velocimetry (EV)) gadgets have ...
Impedance cardiography (ICG) is a low-cost, noninvasive test that measures systolic time intervals and may be a method for ... Impedance cardiography (ICG) is a low-cost, noninvasive test that measures systolic time intervals and may be a method for ... Impedance cardiography (ICG) is a low-cost, noninvasive test that measures systolic time intervals and may be a method for ... Impedance cardiography (ICG) is a low-cost, noninvasive test that measures systolic time intervals and may be a method for ...
In one embodiment, the apparatus comprises a constant current source impedance cardiography (ICG) monitor adapted as a stand- ... can be obtained using impedance cardiography. Strictly speaking, impedance cardiography, also known as thoracic bioimpedance or ... The method generally comprises modeling the thoracic impedance ZT(t) as a constant impedance, Zo, and time-varying impedance, ... a and 2 b are perspective and cross-sectional views, respectively, of a prior art impedance cardiography electrode assembly. ...
Respiration-gated cardiography , Signal analysis related to treatment sites , ... Electrical impedance techniques in tissue-mass detection and characterization. A device is described for measuring electrical ... Respiration-gated cardiography. In a cardiographic apparatus (10), a plurality of electrodes (16) are configured for operative ... An adherent patient device is configured to adhere to the skin of the patient and measure electrocardiogram data, impedance ...
EKG, impedance cardiography, and blood pressure were continuously monitored. The two emotional conditions elicited significant ... Humans, Impedance cardiography, Blood pressure, Anger, Fear, Anxiety, Ragtime film, The Shining film. ...
Other: Impedance cardiography noninvasive measure of cardiac index by impedance cardiography.. Other Name: patients with a ... Non Invasive Measurement of Cardiac Index by Impedance Cardiography. The safety and scientific validity of this study is the ... Non Invasive Measurement of Cardiac Index by Impedance Cardiography. Official Title ICMJE Non Invasive Measurement of Cardiac ... In this study the investigators want to evaluate the impedance cardiography (ICG) as a non invasive method for CI measurement. ...
Impedance Cardiography to Decrease the Risk of Preeclampsia. The safety and scientific validity of this study is the ... Impedance cardiography helps determine whether vasoconstriction or an elevated cardiac output is occurring. The test is easy to ... To determine if the use of impedance cardiography can identify appropriate medications for use in treating chronic hypertensive ... Anti-hypertensive medication prescribed for increased systemic vascular resistance as determined by impedance cardiography ...
... clinicaltrials.gov The purpose of this study is to determine whether outpatient therapeutic management guided by impedance ... Noninvasive impedance cardiography (ICG) is a simple test that utilizes changes in thoracic electrical impedance to measure ... Home » Topics » Heart Failure » Research » PREVENT-HF: Prevention of Heart Failure Events With Impedance Cardiography Testing ... More From BioPortfolio on "PREVENT-HF: Prevention of Heart Failure Events With Impedance Cardiography Testing". *Related ...
Extremely useful for impedance cardiography and ECG signal analysis, ensemble averaging passes can be located around data- ...
Using the Impedance Cardiography signal, various valvular heart diseases (VHD) such as mitral & aortic insufficiency, mitral & ... paper an overview literature survey of the non-invasive methods for measuring the cardiac output by the impedance cardiography ... Using the Impedance Cardiography signal, various valvular heart diseases (VHD) such as mitral & aortic insufficiency, mitral & ... paper an overview literature survey of the non-invasive methods for measuring the cardiac output by the impedance cardiography ...
... ... Materials and Methods: In the last years, impedance cardiography (ICG) is a technique which has gained much attention. However ... CitationEscrivá, J., Gambus, P., Jensen, E.W., Vallverdu, M. Time-frequency features for impedance cardiography signals during ... Time-Frequency Distributions (TFDs) with 5 different kernels are used in order to analyze impedance cardiography signals (ICG) ...
Cardiac Output Measured by Transthoracic Impedance Cardiography at Rest, during Exercise and at Various Lung Volumes A. T. ... 5. Transthoracic impedance cardiography is a rapid, non-invasive technique for measurement of cardiac output. It requires very ... A. T. Edmunds, S. Godfrey, Marion Tooley; Cardiac Output Measured by Transthoracic Impedance Cardiography at Rest, during ... 1. Cardiac output measured by transthoracic impedance cardiography has been compared with simultaneous measurements made by the ...
... with impedance has been to measure changes in thoracic impedance for only those beats of the impedance cardiogram (IC) which ... Stroke volume measurement during supine and upright cycle exercise by impedance cardiography. *Jon K. Moon, Andrew R Coggan, ... Temporal stability of ambulatory stroke volume and cardiac output measured by impedance cardiography.. *Annebet D. Goedhart, ... with impedance has been to measure changes in thoracic impedance for only those beats of the impedance cardiogram (IC) which ...
Whole Body Impedance Cardiography & Continuous Pulse Wave Analysis in the Measurement of Human Haemodynamics during Passive ... Non-invasive haemodynamic measurements were performed by applying whole body impedance cardiography, continuous pulse wave ...
Mean impedance output was 4.5 +/- 1.27 liter/min Reproducibility was comparable for impedance (0.0059 +/- 0.639) and ... Impedance cardiac output values agree and correlate highly with quality-controlled thermodilution outputs across a wide range ... Individual impedance values correlated with paired thermodilution determinations (r = 0.75; p less than 0.0001). Each patients ... In all, 43 patients (14 men and 29 women = 201 pairs) were studied by simultaneously performed impedance and thermal ...
The Impedance Cardiography (ICG or Ztot) signal represents the changes of the thoracic impedance due to variations in the blood ... Woltjer, H.H.; Bogaard, H.J.; de Vries, J.M. (1997). "The technique of impedance cardiography". Eur. Heart J. 18 (9): 1396-1403 ... quantium Medical Cardiac Output (qCO) uses impedance cardiography in a simple, continuous, and non-invasive way to estimate the ... Several authors advocate the high reliability and good correlation of cardiography impedance compared to others techniques more ...
Impedance cardiography K S Rabbani; M Sarker; M H R Akond; T Akter (1999). "Focused Impedance Measurement (FIM): A New ... FIM can be considered a bridge between Four Electrode Impedance Measurement (FEIM) and Electrical impedance Tomography (EIT), ... Identifying zones with specific impedances can provide greater certainty regarding the factors behind the impedance. ... "Thorax mapping for localized lung impedance change using focused impedance measurement (FIM): A pilot study". Electrical ...
Impedance" by people in this website by year, and whether "Cardiography, Impedance" was a major or minor topic of these ... "Cardiography, Impedance" is a descriptor in the National Library of Medicines controlled vocabulary thesaurus, MeSH (Medical ... Below are the most recent publications written about "Cardiography, Impedance" by people in Profiles. ... A type of impedance plethysmography in which bioelectrical impedance is measured between electrodes positioned around the neck ...
Impedance Cardiography is a useful diagnostic tool with External Counterpulsation (ECP and EECP) Therapy to track improvements ... Filed Under: ECP Message Boards Tagged With: ecp therapy with impedance cardiography icg, eecp with icg, impedance cardiography ... Impedance Cardiography (ICG). October 16, 2013. External Counterpulsation Therapy has proven to remarkable benefits to overall ... Impedance Cardiography (ICG). ICG is a diagnostic tool that measures 12 different parameter relating to Flow, Resistance, ...
Impedance Cardiography (ICG) is a simple diagnostic tools that derives 12 parameters related to cardiac flow, resistance, ... Filed Under: ECP Message Boards Tagged With: ecp therapy with impedance cardiography icg, eecp with icg, impedance cardiography ... Impedance Cardiography (ICG). ICG is a diagnostic tool that measures 12 different parameter relating to Flow, Resistance, ... in conjunction with Impedance Cardiography, you email our staff at [email protected] ...
Impedance cardiography (ICG) is a noninvasive and low-cost method of examination. The survey technique is simple and ICG ... Impedance cardiography (ICG) is a noninvasive and low-cost method of examination. The survey technique is simple and ICG ... Comparing impedance cardiography and echocardiography in the assessment of reduced left ventricular systolic function. ... Thompson B, Drazner MH, Dries DL, Yancy CW: Systolic time ratio by impedance cardiography to distinguish preserved vs impaired ...
Impedance cardiography. Impedance cardiography (ICG) is a method which calculates CO from the measurement of changes in ... Electrical impedance, or simply impedance, is a measure of opposition to a sinusoidal alternating electric current. ... ... Impedance cardiography is a hemorheology technique of using sensors to detect the properties of the blood flow in the Thorax ... Lower impedance indicates greater the intrathoracic fluid volume, and as the only fluid volume which changes beat to beat ...
Utility of impedance cardiography for the identification of short-term risk of clinical decompensation in stable patients with ... Bour J, Kellett J. Impedance cardiography - a rapid and cost-effective screening tool for cardiac disease. Eur J Intern Med. ... Obesity Hypertension Impedance cardiography Body mass index Cardiac index Systemic vascular resistance index ... Kamath S, Drazner M, Tasissa G, Rogers J, Stevenson L, Yancy C. Correlation of impedance cardiography with invasive hemodymanic ...
The Effect of Peripheral Resistance on Impedance Cardiography Measurements in the Anesthetized Dog. Critchley, Lester A. H.; ... IMPLICATIONS: Impedance cardiac output measurements are influenced by peripheral resistance such that cardiac output will be ... underestimated by the impedance method when resistance is low and overestimated when resistance is high. ...
Impedance cardiography permits continuous noninvasive monitoring of hemodynamic variables on a beat to beat basis. Methods. ... The purpose of this study was to evaluate the ability of impedance cardiography to determine the change in cardiac output ... 1) Impedance cardiography allows highly reproducible noninvasive assessments of cardiac output in pacemaker patients; 2) ... Eleven patients with a DDD pacemaker were evaluated by impedance cardiography. Stroke volume, cardiac output and total ...
Impedance cardiography system computer-based CardioScreen 1000 medis Medizinische Messtechnik CardioScreen 1000 ...
Cardiography, Impedance. *Diastole/physiology. *Elasticity. *Heart Failure/diagnosis/*physiopathology/therapy. *Heart Function ...
  • Thoracic impedance cardiography (ICG) allows continuous, non-invasive SV assessment. (biomedcentral.com)
  • Thoracic impedance cardiography (ICG) may overcome some of the disadvantages of the other methods. (biomedcentral.com)
  • ICG is a method of non-invasively estimating SV and assessing haemodynamic status via ECG surface electrodes, using complex algorithms to convert changes in thoracic impedance into volume changes. (biomedcentral.com)
  • Most research employing impedance cardiography , which provides noninvasive and affordable measurements of the cardiovascular response, has focused on the study of exercise physiology (Bogaard et al. (freethesaurus.com)
  • Impedance cardiography (ICG) is a low-cost, noninvasive test that measures systolic time intervals and may be a method for detecting impaired vs intact EF. (elsevier.com)
  • Impedance cardiography seems to be a very good, although underappreciated diagnostic method. (openrepository.com)
  • Although children's measures of heart rate and blood pressure have been found to be reliable, the reliability of impedance cardiography derived measures have not been evaluated. (bgsu.edu)
  • Impedance cardiography (ICG) allows to measure parameters of heart mechanical function. (edu.pl)
  • These findings suggest children's cardiovascular reactivity to laboratory stressors can be reliably and consistently assessed using impedance cardiography. (bgsu.edu)
  • ICG is sensitivity to movement artifacts inter alia breathing, which distorts impedance signal. (edu.pl)
  • Smith [ 3 ] highlighted many of the flaws to the assumptions made by ICG in an older, but still very relevant, letter to the editor, including the effect on impedance of the body size and shape, resistivity of blood and regional blood flow. (biomedcentral.com)
  • CardioDynamics, the ICG Company, is the innovator and leader of animportant medical technology called impedance cardiography. (medindia.net)
  • A type of impedance plethysmography in which bioelectrical impedance is measured between electrodes positioned around the neck and around the lower thorax. (wakehealth.edu)
  • Furthermore a system to assess the relationship between internal pressure and diameter change of the artery was also developed by using the tonometry and the impedance plethysmography. (nii.ac.jp)
  • The IsenseU-BP+ device presented in this article measures single channel ECG, impedance cardiography and photo plethysmography at the chest. (sintef.no)
  • Non-invasive haemodynamic measurements were performed by applying whole body impedance cardiography, continuous pulse wave analysis and plethysmographic finger blood pressure measurements in supine position and during head-up tilt. (coronetbooks.com)
  • For vascular parameters and for control purposes pulmonary artery Swan-Ganz catheter, calibrated external pulse recordings, whole body impedance cardiography, and transpulmonel thermodilution method were applied. (diva-portal.org)
  • The purpose of this study was to compare the systolic time intervals (STI) obtained by impedance cardiography and by the conventional carotid technique. (forskningsdatabasen.dk)
  • Impedance cardiography (ICG) is a low-cost, noninvasive test that measures systolic time intervals and may be a method for detecting impaired vs intact EF. (elsevier.com)
  • Abstract: Electrical impedance tomography (EIT) is an promising imaging technology for continuous bedside monitoring of ventilation and perfusion. (worldcat.org)
  • Noninvasive impedance cardiography (ICG) is a simple test that utilizes changes in thoracic electrical impedance to measure thoracic fluid content, changes in the duration of cardiac ejection and the velocity of blood flow within the aorta. (bioportfolio.com)
  • Can noninvasive impedance cardiography (ICG) now be used to measure CO (COICG) in place of COTD? (ebscohost.com)
  • Bioimpedance signal (BIS) represents the aorta impedance variation during the heart cycle activity. (scirp.org)
  • We performed a retrospective analysis of 202 patients followed at our Hypertension Clinic with the diagnosis of primary HT and who performed an impedance cardiography (ICG) test. (springer.com)
  • SAN DIEGO, May 15 /PRNewswire-FirstCall/ -- CardioDynamics (Nasdaq: CDICD), the innovator and leader of Impedance Cardiography (ICG) technology and manufacturer of BioZ(R) noninvasive cardiac monitoring systems, today announced the presentation of a significant independent ICG clinical study at the Twenty-third Annual American Society for Hypertension (ASH) Scientific Meeting in New Orleans, Louisiana. (bio-medicine.org)
  • Transthoracic electrical impedance (or admittance) cardiography is a simple technique for the non-invasive and continuous monitoring of stroke volume or cardiac output by detecting the electrical impedance of a thorax which is roughly assumed to be a two-compartment coaxial cylindrical model composed of the aorta and its surrounding thoracic tissues. (biomedsearch.com)
  • 1. Cardiac output measured by transthoracic impedance cardiography has been compared with simultaneous measurements made by the indirect Fick CO 2 rebreathing method in nine adults and 14 children. (portlandpress.com)
  • The conventional method of calculating stroke volume (SV) with impedance has been to measure changes in thoracic impedance for only those beats of the impedance cardiogram (IC) which cross on a specific baseline. (semanticscholar.org)
  • Thoracic impedance cardiography (ICG) allows continuous, non-invasive SV assessment. (biomedcentral.com)
  • Introduction: Impedance cardiography (IC) derived from morphological analysis of the thoracic impedance signal is now commonly used for noninvasive assessment of cardiac output (CO) at rest and during exercise. (northumbria.ac.uk)
  • A. P. Hills and N. M. Byrne, "Bioelectrical impedance and body composition assessment," Malaysian Journal of Nutrition , vol. 4, pp. 107-112, 1998. (hindawi.com)
  • W. J. Rutherford, "Comparison of bioelectrical impedance and skinfolds with hydrodensitometry in the assessment of body composition in healthy young adults," Journal of Research , vol. 6, no. 2, pp. 56-60, 2011. (hindawi.com)
  • M. E. Orazem and B. Tribollet, Impedance Spectroscopy , The ECS Series of Texts and Monographs, Wiley-Inter Sc, 2008. (hindawi.com)
  • T. Repo, D. H. Paine, and A. G. Taylor, "Electrical impedance spectroscopy in relation to seed viability and moisture content in snap bean ( Phaseolus vulgaris L.)," Seed Science Research , vol. 12, no. 1, pp. 17-29, 2002. (hindawi.com)
  • The usefulness of bioelectrical impedance analysis in differentiating dyspnea due to decompensated heart failure," Journal of Cardiac Failure , vol. 14, no. 8, pp. 676-686, 2008. (hindawi.com)
  • D. A. Schoeller, "Bioelectrical impedance analysis. (hindawi.com)
  • The hemodynamic pattern and thoracic fluid content were evaluated by impedance cardiography . (bvsalud.org)
  • Parameters of blood flow, vascular resistance, myocardial contractility and thoracic fluid content were measured in a 10-minute supine resting test by impedance cardiography. (aaem.pl)
  • 7. A method according to claim 6 , also including determining a third parameter of the patient's thorax, in addition to the two specific impedances of tissue of the lungs. (google.ca)
  • 2 . The method of claim 1 , in which the sensing includes detecting a change in a baseline thoracic impedance associated with fluid buildup in a portion of a thorax of the subject. (google.es)
  • Identifying zones with specific impedances can provide greater certainty regarding the factors behind the impedance. (wikipedia.org)
  • 2. A method according to claim 1 , wherein the model of the chest treats the specific impedances of tissue of the two lungs as two independent variables. (google.ca)
  • 5. A method according to claim 1 , wherein determining the specific impedance of tissue of at least one lung comprises determining the specific impedances of tissue of both lungs. (google.ca)
  • 9. A method according to claim 6 , wherein a least squares method is used to find a fit of the two specific impedances of tissue of the lungs to the at least three impedance measurements. (google.ca)
  • 12. A method according to claim 1 , wherein determining the specific impedance of tissue of at least one lung comprises determining the specific impedance of tissue of the lung responsive to a solution of equations that satisfy constraints defined by the first and second impedance measurements, for a model of the chest with two specific impedances of lung tissue as unknowns. (google.ca)
  • quantium Medical Cardiac Output (qCO) uses impedance cardiography in a simple, continuous, and non-invasive way to estimate the Cardiac output (CO) and other hemodynamic parameters such as the Stroke Volume (SV) and Cardiac index (CI). (wikipedia.org)
  • Impedance cardiography permits continuous noninvasive monitoring of hemodynamic variables on a beat to beat basis. (bgu.ac.il)
  • The provision of guidance in ventilator therapy by continuous monitoring of regional lung ventilation, aeration and respiratory system mechanics is the main clinical benefit of electrical impedance to. (bioportfolio.com)
  • Impedance cardiography (ICG) is a known non-invasive method which allows continuous estimation of Cardiac Output of the heart of a patient. (tu-ilmenau.de)
  • METHODS: In the present study the variations in blood volume, stroke volume, cardiac output and systemic vascular resistance were investigated in 68 patients on chronic intermittent hemodialysis utilizing bioelectrical impedance cardiography. (biomedsearch.com)
  • The objective of this study was to analyze the acute haemodynamic effects of A-V intervals programmed at different lengths in dual-chamber stimulation, ascertained by determining stroke volume with impedance cardiography. (uni-marburg.de)
  • Materials and Methods: In the last years, impedance cardiography (ICG) is a technique which has gained much attention. (upc.edu)
  • 2. Impedance measurements of cardiac output were consistently higher than indirect Fick measurements of cardiac output, but after application of a correction factor related to packed cell volume there was close correlation between the results obtained by the two methods ( r = 0·94). (portlandpress.com)
  • Thoracic impedance cardiography (ICG) may overcome some of the disadvantages of the other methods. (biomedcentral.com)
  • Both methods had a high degree of reproducibility and this parameter was significantly better within the same day, when impedance cardiography was used (p less than 0.01). (forskningsdatabasen.dk)
  • We furthermore conclude that both methods are reliable, but we recommend the use of impedance cardiography because it is easier to apply, it may be more precise and it can be used for simultaneous measurements of other haemodynamic variables. (forskningsdatabasen.dk)
  • Background: Both serum measurements of B-type natriuretic peptide (BNP) and impedance cardiography (ICG) are used to evaluate patients for congestive heart failure (CHF) in the Emergency Department (ED), but the agreement between the data obtained by these two methods remains uncertain. (elsevier.com)
  • For this purpose an additional bio-medical signal of the peripheral pulse wave the impedance plethysmographic (IPG) curve and its interaction with the impedance cardiographic (ICG) signal of the heart have been evaluated using new methods of signal analysis and modeling to identify new information suitable to appraise the expectable accuracy of impedance cardiography. (tu-ilmenau.de)
  • Methods: The study was carried out with 42 patients who had a dual-chamber pacemaker or dual chamber ICD implanted, and the A-V interval was optimized by impedance cardiography. (uni-marburg.de)
  • 11. A method according to claim 10 , wherein calculating expected impedance measurements comprises using one or more of a finite element method, a finite difference method, a finite boundary element method, and a finite volume method. (google.ca)
  • Regional pulmonary effects of bronchoalveolar lavage procedure determined by electrical impedance tomography. (bioportfolio.com)
  • Impedance Cardiography: Can It Replace Thermodilution and the Pulmonary Artery Catheter? (ebscohost.com)
  • Kubicek WG, Karnegis JN, Patterson RP, Witsoe DA, Mattson RH (1966) Development and evaluation of an impedance cardiac output system. (springer.com)
  • Most research employing impedance cardiography , which provides noninvasive and affordable measurements of the cardiovascular response, has focused on the study of exercise physiology (Bogaard et al. (freethesaurus.com)
  • Cardiography, Impedance" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (wakehealth.edu)
  • Objective tests of middle ear function based on the difficulty (impedance) or ease (admittance) of sound flow through the middle ear. (bioportfolio.com)
  • Gaw RL, Cornish BH, Thomas BJ (2007) Comparison of a theoretical impedance model with experimental measurements of pulsatile blood flow. (springer.com)
  • In order to investigate the contribution of arterial radius and center-line velocity to the blood conductivity and electrical impedance of pulsatile flow in the human common carotid artery, we proposed three simplified mathematical models to describe the relationship between the center-line velocity, the arterial radius, and the blood conductivity. (springer.com)
  • Apfel H (1990) Electrical impedance of the carotid artery in response to various types of stress. (springer.com)
  • Objective: This works investigates the time-frequency content of impedance cardiography signals during a propofol-remifentanil anesthesia. (upc.edu)
  • Time-Frequency Distributions (TFDs) with 5 different kernels are used in order to analyze impedance cardiography signals (ICG) before the start of the anesthesia and after the loss of consciousness. (upc.edu)
  • 2) the advantage of RIC is the use of peripheral rather than thoracic impedance signals, supported by correcting factors. (ne.jp)
  • 7. The apparatus of claim 4 , wherein said first signals comprise an impedance waveform, said second signals comprise ECG signals, and said computer program is adapted to identify at least one fiducial point within each of said impedance waveform and said ECG signals. (google.com)
  • Electrical Impedance Tomography (EIT) is an emerging medical imaging technique which can produce tomographic images of internal impedance changes within an object using non-penetrating surface electro. (bioportfolio.com)
  • Bi-frequency symmetry difference electrical impedance tomography - a novel technique for perturbation detection in static scenes. (bioportfolio.com)
  • Kubicek, W.G., Patterson, R.P. and Witsoe, D.A. (1970) Impedance Cardiography as a Non Invasive Method of Monitoring Cardiac Function and Other Parameters of the Cardiovascular System. (scirp.org)
  • Impedance cardiography (ICG) is a simple and inexpensive method to acquire data on hemodynamic parameters. (cst.com)
  • The phase angle (see Figure 7-1 ), which has been found to be important for describing relationships between bioelectrical impedance and the body and for measuring physiological variables (Baumgartner et al. (nap.edu)
  • A measure of impedance (Z) is composed of the sum of two vectors, resistance (R) and reactance (Xc), measured at a particular frequency and is described mathematically by the equation Z 2 = R 2 + Xc 2 . (nap.edu)
  • FIGURE 7-1 Impedance plot curve of resistance and reactance with frequency. (nap.edu)
  • 4. Haemodynamic and autonomic response, both at rest and at 70°, by impedance cardiography. (bmj.com)
  • Acute haemodynamic effects of optimizing the A-V interval with impedance cardiography in dual-chamber stimulation Background: Optimizing the A-V interval in dual-chamber stimulation may improve haemodynamics. (uni-marburg.de)
  • Peura RA, Penney BC, Arcuri J, Jr AF, Wheeler HB (1978) Influence of erythrocyte velocity on impedance plethysmographic measurements. (springer.com)
  • The purpose of this study was to evaluate the ability of impedance cardiography to determine the change in cardiac output caused by modifications in the atrioventricular (AV) delay in DDD (dual-chamber) pacing mode while pacing the atrium and ventricle at different programmed rates. (bgu.ac.il)
  • The goal of this feasibility study is to evaluate the ability of Electrical Impedance Tomography (EIT) for providing regional and quantitative information about the extent and nature of br. (bioportfolio.com)
  • Exercising women have a better outcome than the control group, when evaluated both with impedance cardiography and with applanation tonometry. (aaem.pl)
  • b) determining the specific impedance of tissue of at least a first one of the patient's lungs substantially independently of specific impedance of tissue of the second one of the patient's lungs, such that Poisson's equation for a model of the chest has a solution consistent with the at least two impedance measurements. (google.ca)
  • Exciting new upgrades see the addition of " best-in-class" Pulse Pressure Waveform Analysis (PPWA) and High Definition Impedance Cardiography (HD-ICG) to the proven ODM Doppler flow-based platform. (deltexmedical.com)
  • This article briefly describes the research history of bioelectrical impedance, the status of present research related to body composition and future research directions. (nap.edu)
  • b) using the impedance measurements to determine the impedance of at least one of the lungs substantially independently of impedance of the other lung. (google.ca)