Abstract：
:Following a step increase in sarcomere length, isometric cardiac muscle tension increases instantaneously by the Frank-Starling mechanism. In isolated papillary muscle and myocytes, there is an additional significant rise in developed tension over the following 15 min due to an unknown mechanism. This slow change in tension could not be explained by mechanical heterogeneity of the muscle preparations or by an increase in myofilament sensitivity to Ca2+. The slow change in tension was not dependent on sarcoplasmic reticulum Ca2+ loading assessed with rapid cooling contractures, and was not significantly altered by sarcoplasmic reticulum Ca2+ depletion (ryanodine) or inhibition of sarcoplasmic reticulum Ca2+ reuptake (cyclopiazonic acid). We used the Luo-Rudy ionic model of the ventricular myocyte together with a model of the length-dependent myofilament activation by Ca2+ to examine the effects of step changes in the parameters of sarcolemmal ion fluxes as possible mechanisms for the slow change in stress. The slow increase in tension was simulated by step changes in the Na+-K+ pump or Na+ leak currents, suggesting that the slow change in stress may be caused by length induced changes in Na+ fluxes. The model also predicted a slow increase in the magnitude of the initial repolarization during phase 1 of the action potential. The combination of experimental and computational models used in this investigation represents a valuable technique in elucidating the cellular mechanisms of fundamental processes in cardiac excitation-contraction coupling.
journal_name
J Electrocardioljournal_title
Journal of electrocardiologyauthors
Bluhm WF,Sung D,Lew WY,Garfinkel A,McCulloch ADdoi
10.1016/s0022-0736(98)90273-4subject
Has Abstractpub_date
1998-01-01 00:00:00pages
13-22eissn
0022-0736issn
1532-8430journal_volume
31 Supplpub_type
杂志文章abstract：BACKGROUND:Some patients with ongoing heart failure symptoms after treatment with cardiac resynchronization therapy (CRT) demonstrate QRS prolongation during exercise. We investigated whether the optimal CRT pacing configuration changes during dobutamine stress. METHODS:Seven patients undergoing CRT implantation under...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2020.08.012
更新日期：2020-01-01 00:00:00
abstract：:New developments in instrumentation, in clinical application, as well as in data analysis and visualization have provided new momentum to magnetocardiography (MCG). On one hand robust, easy to use and budget-priced MCG-systems entered the market and are applied to a multi-centred clinical study. On the other hand high...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2004.08.035
更新日期：2004-01-01 00:00:00
abstract：:Direct Wenckebach periods in the left bundle branch with periods of 4:3 and 5:4 conduction alternating with 2:1 left bundle branch block (LBBB) were observed in a patient who was admitted because of congestive heart failure. There was no previous documented LBBB and serial electrocardiographic (ECG) mainfestations aft...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(80)80034-3
更新日期：1980-01-01 00:00:00
abstract：:Recent studies have reported the relation between Torsade de Pointes (TdP) and midmyocardial (M) cell function associated with long QT syndrome. To investigate this relation, we conducted a simulation study with a three-dimensional (3D) heart model incorporating M cells in the anterolateral areas of the model. Paramet...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(98)90308-9
更新日期：1998-01-01 00:00:00
abstract：:Precise recording of the standard 12-lead electrocardiogram (ECG) is technically time consuming. Placing limb leads on the torso has the major advantages of ease of use, increased speed of application, and decreased artifact. This modified ECG frequently substitutes for the standard 12-lead ECG in intensive care units...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2007.11.004
更新日期：2008-05-01 00:00:00
abstract：:This report presents an unusual type of conduction disturbance of the left bundle branch which appeared in a patient with acute bacterial endocarditis of the aortic valve in which the septum was also invaded. This is the first case found in which the partial left bundle branch block (LBBB) was of acute inflammatory or...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(77)80073-3
更新日期：1977-07-01 00:00:00
abstract：:Heart muscle diseases are traditionally classified according to their peculiar pathophysiologic features such as "dilated," "hypertrophic," "restrictive," and "arrhythmogenic right ventricular" cardiomyopathy. The extraordinary advances accomplished in the last two decades in molecular genetics have allowed the identi...
journal_title：Journal of electrocardiology
pub_type： 杂志文章,评审
doi：10.1016/j.jelectrocard.2005.06.101
更新日期：2005-10-01 00:00:00
abstract：:The authors present a patient who initially underwent anterior approach atrioventricular (AV) nodal modification for treatment of typical AV junctional reentrant tachycardia (AVJRT) and subsequently developed clinical episodes of a previously undocumented type of supraventricular tachycardia. Findings during electroph...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(05)80113-x
更新日期：1994-01-01 00:00:00
abstract：AIMS:This investigation addresses procedural characteristics of catheter ablation in patients with atrial fibrillation (AF) and sinus bradycardia. METHODS:From the prospective, multi-center German Ablation Registry 1073 patients with sinus rhythm at the time of AF ablation were divided into two groups according to hea...
journal_title：Journal of electrocardiology
pub_type： 杂志文章,多中心研究
doi：10.1016/j.jelectrocard.2015.12.007
更新日期：2016-03-01 00:00:00
abstract：:Unexplained sudden deaths following use of pentavalent antimonial drugs have been described, presumably owing to ventricular arrhythmias. A patient is reported with QT interval prolongation and syncopal episodes related to torsade de pointes following treatment of visceral leishmaniasis with meglumine antimoniate. Thi...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(97)80023-4
更新日期：1997-04-01 00:00:00
abstract：:An interpolated premature ventricular contraction (PVC) may produce either complete block of the next sinus impulse or depression of A-V nodal conduction with a prolonged A-H interval. When a PVC results in partial depression of a A-V nodal conduction, the effect on subsequent premature atrial stimuli is unknown. The ...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(77)80025-3
更新日期：1977-01-01 00:00:00
abstract：:VPC morphology was studied in the surface 12-leads ECGs (resting) in one hundred and thirty-six patients over a none-month period (January-September, 1978). Seventy four (54%) of these had coronary artery disease proven by cardiac catheterization (61) or by evidence of acute transmural myocardial infarction (13) diagn...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(80)80083-5
更新日期：1980-10-01 00:00:00
abstract：BACKGROUND AND PURPOSE:Descriptions of the significance of ST segment or QRS abnormalities in myocarditis are limited because documentation of the diagnosis has previously required myocardial biopsy. Late gadolinium enhancement (LGE) and T2 weighted imaging in the midventricular wall on cardiac magnetic resonance imagi...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2014.07.018
更新日期：2014-11-01 00:00:00
abstract：:A low-cost micro-processor combined with a standard 3-channel electrocardiographic recorder was adapted to polar coordinate conversion of Frank orthogonal lead signals and display of the resultant polarcardiogram. The processor also functions as a computer of average transients for the ECG complexes and provides autom...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(82)80047-2
更新日期：1982-01-01 00:00:00
abstract：:In the last 10 years the molecular substrate of a diversity of primary electrical diseases has been unraveled. Disease-causing mutations in ion-channel genes have been identified and have challenged clinical and basic electrophysiologists to mechanistically link the observed genetic aberrancies to the phenotype. Indee...
journal_title：Journal of electrocardiology
pub_type： 杂志文章,评审
doi：10.1016/j.jelectrocard.2005.06.103
更新日期：2005-10-01 00:00:00
abstract：:Clinically based studies have indicated that patients who have suffered myocardial infarction (MI) exhibit lower heart rate variability (HRV). Such associations have not been reported at the population level. To investigate whether MI is related to lower HRV in the general population, the authors examined a stratified...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(96)80082-3
更新日期：1996-07-01 00:00:00
abstract：:Thoracic electromaps were recorded before and after sublingual nitroglycerin (NG) in 26 subjects 15 and 30 days after acute myocardial infarction (MI), in order to evaluate the effect of the drug on injury potentials. Ten patients with documented left ventricular aneurysm were also studied 5 to 46 months after acute M...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(81)81007-2
更新日期：1981-10-01 00:00:00
abstract：:Left ventricular systolic function, determined mainly by final infarct size, has a major influence on prognosis after acute myocardial infarction (MI). It was found that infarct size and left ventricular ejection fraction can be predicted using the Selvester QRS-score in patients not receiving reperfusion therapy. We ...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1054/jelc.200.20345
更新日期：2000-01-01 00:00:00
abstract：:Recent studies have shown that ventricular myocardium is composed of at least 3 electrophysiologically distinct cell types: epicardial, endocardial, and M cells. Action potentials recorded from epicardial and M cells, unlike those recorded from endocardium, display a spike-and-dome morphology, the result of a prominen...
journal_title：Journal of electrocardiology
pub_type： 杂志文章,评审
doi：10.1016/s0022-0736(99)90074-2
更新日期：1999-01-01 00:00:00
abstract：:There is an increased risk of sudden cardiac death (SCD) and sudden cardiac arrest (SCA), in African Americans, the basis of which is likely multifactorial. African Americans have higher rates of traditional cardiac risk factors including hypertension, left ventricular hypertrophy, diabetes, coronary heart disease, an...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2014.07.023
更新日期：2014-11-01 00:00:00
abstract：BACKGROUND:Electrocution injury (EI) is a major problem in developing countries. The aim of this study is to investigate the effect of EI on electrocardiographic (ECG) parameters. METHODS:A total of 43 patients hospitalized with diagnosis of EI were prospectively enrolled. Admission ECGs were compared with follow-up E...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2015.06.009
更新日期：2015-09-01 00:00:00
abstract：:A successive RR interval plot was developed to analyze arrhythmia. The plot consisted of a set of points with the x-value of (N)th RR interval and the y-value of (N + 1)th RR interval. This method was applied in the arrhythmia analysis of Holter electrocardiograms obtained from 35 patients. In the analysis of ventricu...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/0022-0736(90)90163-v
更新日期：1990-07-01 00:00:00
abstract：BACKGROUND:The ventricular repolarization (VR) response to short-lasting coronary occlusion has been characterized by 3-dimensional vectorcardiography during angioplasty in humans; the T-vector loop becomes distorted (increased T(avplan)) and more circular (decreased T(eigenvalue)), but these changes have not been rela...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2008.11.001
更新日期：2009-05-01 00:00:00
abstract：:Left bundle branch block (LBBB), traditionally viewed as an electrophysiologic abnormality, is increasingly recognized for its profound hemodynamic effects. LBBB causes asynchronous myocardial activation, which, in turn, may trigger ventricular remodeling. Exercise nuclear studies frequently show reversible perfusion ...
journal_title：Journal of electrocardiology
pub_type： 杂志文章,评审
doi：10.1054/jelc.2000.20330
更新日期：2000-01-01 00:00:00
abstract：:Initial electrical forces emanating from interventricular septal depolarization, being directed to the right and anteriorly, normally produce an initial negative deflection or Q wave in leads I, aVL and V6 and an initial positive deflection or R wave in leads V1 and V2. The observations of hypertrophied interventricul...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(81)80044-1
更新日期：1981-01-01 00:00:00
abstract：:Precordial electrocardiographic leads V1, V2, V5, V6, and limb leads I and II were recorded simultaneously utilizing radio transparent electrodes and wire leads during coronary angiography in 35 patients with obstructive coronary disease and in 17 subjects with normal coronary angiograms. The pattern of electrocardiog...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(76)80047-7
更新日期：1976-01-01 00:00:00
abstract：BACKGROUND:Electrocardiogram (ECG) biometrics is an advanced technology, not yet covered by guidelines on criteria, features and leads for maximal authentication accuracy. OBJECTIVE:This study aims to define the minimal set of morphological metrics in 12-lead ECG by optimization towards high reliability and security, ...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2016.07.021
更新日期：2016-01-01 00:00:00
abstract：:A 53-year-old woman with sinus node dysfunction underwent dual-chamber pacemaker implantation through a persistent left superior vena cava draining into the coronary sinus, which was detected at the time of implantation. We managed to fix the ventricular lead in the right ventricular (RV) apex by forming a clockwise l...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2007.05.016
更新日期：2007-11-01 00:00:00
abstract：:Using standard biopolar, temporary pacing catheters, thresholds were measured in four configurations: (1) bipolar (distal electrode negative, proximal electrode positive); (2) distal unipolar (distal electrode negative, right arm electrode positive); (3) proximal unipolar (proximal electrode negative, right arm electr...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(76)80077-5
更新日期：1976-04-01 00:00:00
abstract：:Magnesium ion infusion has been reported for treatment of hypomagnesemia often associated with myocardial infarction and with surgeries involving cardiopulmonary bypass (CPB). Magnesium infusion before CPB has been reported to adversely affect the ability to defibrillate after CPB. However, there are also reports of m...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(98)90045-0
更新日期：1998-04-01 00:00:00
