Abstract：
:This study employs a bifurcation analysis approach to elucidate the effect of the key ion channels on cardiac arrhythmias and thereby explain the efficacy of antiarrhythmic drugs in controlling arrhythmias. The model used for the analysis contains the key ion channels involved in the ventricular action potential--fast sodium, slow calcium, and background potassium channels. The cardiac tissue is modeled by a ring structure. The bifurcation diagram reveals that at a certain ring size, the amplitude of the action potential suddenly shrinks and the conduction velocity (CV) becomes unstable. Instability in CV leads to termination of reentrant arrhythmias. This ring size (ie, the critical ring size [CRS]) depends of the type of channel blocker. Blocking of the sodium channel leads to a decrease in the CRS, which in turn enhances stable reentry (proarrhythmia). Although calcium channel blockers do not alter the CV, they can exert the proarrhythmic effect by drastically shortening the CRS. The potassium channel blockers, on the other hand, are effective in controlling reentry in ventricular tissues by lengthening the CRS. Near blocking of the potassium channel, however, brings about another type of arrhythmia--the formation of ectopic foci. In the neighborhood of the CRS, the cycle length oscillates with an interesting pattern that depends on ring size and drug type. Although a critical reentrant loop length for stable reentrant excitation has been investigated for a long time, this study is the first demonstration of how the key ion channels in the plasma membrane affect the loop length. Furthermore, the analysis approach provides a theoretical basis for the increased mortality associated with class I drug use in the Cardiac Arrhythmia Suppression Trial Team.
journal_name
J Electrocardioljournal_title
Journal of electrocardiologyauthors
Chay TRdoi
10.1016/s0022-0736(95)80055-7subject
Has Abstractpub_date
1995-01-01 00:00:00pages
191-7eissn
0022-0736issn
1532-8430journal_volume
28 Supplpub_type
杂志文章abstract：:The authors investigated the usefulness of the Karhunen-Loeve technique applied to body surface maps to study regional cardiac excitation. Eigenvectors were derived from the body surface potential maps of 120 healthy adults using the Karhunen-Loeve expansion theory. Then, in the maps of various types of ventricular hy...
journal_title：Journal of electrocardiology
pub_type： 临床试验,杂志文章
doi：10.1016/0022-0736(90)90148-u
更新日期：1990-01-01 00:00:00
abstract：:Hypertrophic cardiomyopathy (HCM) have been reported to display impaired heart rate variability, although little is known regarding its prognostic value. By using fast Fourier transformation of 24-hour Holter recordings in 73 HCM patients at a stable clinical condition, we computed 4 spectral components: very low freq...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2003.08.005
更新日期：2003-10-01 00:00:00
abstract：:Repetitive nonreentrant ventriculoatrial synchrony during dual-chamber pacing is characterized by long intervals alternating with short intervals. This arrangement activated automatic mode switching in a St Jude dual-chamber pacemaker in which the algorithm requires an atrial sensed event for automatic mode switching ...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2012.04.003
更新日期：2012-07-01 00:00:00
abstract：BACKGROUND:ECG cable interchange can generate erroneous diagnoses. For algorithms detecting ECG cable interchange, high specificity is required to maintain a low total false positive rate because the prevalence of interchange is low. In this study, we propose and evaluate an improved algorithm for automatic detection a...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2014.08.006
更新日期：2014-11-01 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：:Many electrocardiographic criteria have been proposed for the differentiation of ventricular extrasystole and supraventricular conduction with aberrancy in atrial fibrillation but the validity of these have not been confirmed by intracardiac studies. We recorded His bundle electrograms in nineteen patients (eleven men...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(85)80033-9
更新日期：1985-01-01 00:00:00
abstract：:Takotsubo cardiomyopathy (TTC) is characterized by acute and reversible ventricular dysfunction in the absence of significant coronary artery disease, typically triggered by acute emotional or physical stress. In the acute phase of TTC, the electrocardiogram (ECG) shows ST-segment elevation, which rapidly evolves into...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2013.02.005
更新日期：2013-07-01 00:00:00
abstract：BACKGROUND:Electrocardiogram (ECG) screening in athletes enhances the detection of conditions associated with sudden cardiac death (SCD), but concerns remain for false positive results when conducted outside of specialized centers. This study compared ECG interpretation in college athletes between local physicians and ...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2020.08.002
更新日期：2020-01-01 00:00:00
abstract：OBJECTIVE:The purpose of this study is to investigate the effect of cardiac resynchronization therapy (CRT) on P wave maximum duration (PWM) and P wave dispersion (PWD) in patients with advanced heart failure. METHODS:Forty-six patients (33 men; mean age, 60 +/- 11 years) with CRT were enrolled in the present study. P...
journal_title：Journal of electrocardiology
pub_type： 临床试验,杂志文章
doi：10.1016/j.jelectrocard.2009.02.005
更新日期：2009-07-01 00:00:00
abstract：:15-Year-old man's cardiac event monitor showed an episode of wide complex tachycardia which transitioned into narrow complex tachycardia. The tachycardia cycle length was shorter during wide complex tachycardia compared with narrow complex tachycardia. He underwent electrophysiology study in which an orthodromic atrio...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2020.02.002
更新日期：2020-01-01 00:00:00
abstract：:This article concerns a currently reported hypothesis explaining the alternations of conduction time during intra atrioventricular (AV) nodal reentrant tachycardia (AVNRT). This hypothesis supposes simple mutual influence of sequences of intranodal conduction during reentry tachycardia that use the same circuit in dif...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/0022-0736(89)90024-1
更新日期：1989-01-01 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：:Body surface isopotential maps around early ventricular activation were investigated in 30 normal subjects by the use of the authors' signal-averaged body surface mapping system. The number of beats averaged was 96-154 (mean, 127). Two distinct patterns were recognized in the appearance of a maximum at the onset of ve...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/0022-0736(91)90025-h
更新日期：1991-07-01 00:00:00
abstract：BACKGROUND:An association between paroxysmal supraventricular tachycardias (PSVT) and elevated cardiac troponin I (cTnI) has been reported in small studies, even in the absence of significant coronary artery or structural heart disease. We sought to explore the prognostic significance of elevated cTnI among patients pr...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2020.09.001
更新日期：2020-01-01 00:00:00
abstract：INTRODUCTION:The right ventricular myocardial infarction (RVMI) has traditionally been mainly related to inferior wall ST elevation myocardial infarction (STEMI). This study assessed the RVMI electrocardiographic (ECG-RVMI) signs in relationship to ECG-based STEMI localization and to the infarct related artery in patie...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2016.08.001
更新日期：2016-01-01 00:00:00
abstract：:While ST-segment elevation (STE) on ECG is widely recognized as representing myocardial infarction or injury such as coronary occlusion or pericarditis, STE may occasionally ensue from non-cardiac etiologies. Indeed, gastrointestinal disorders causing STE are not well documented in the literature. We present a case wh...
journal_title：Journal of electrocardiology
pub_type： 杂志文章,评审
doi：10.1016/j.jelectrocard.2017.04.001
更新日期：2017-01-01 00:00:00
abstract：:We studied the use of cardiac magnetic field mapping to detect patients with CAD without subjecting them to stress. Fifty-nine healthy control subjects and 101 patients with CAD without previous MI were included. The optimal positions for detecting CAD were located in the left superior parasternal and in the inferior ...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2007.03.013
更新日期：2007-09-01 00:00:00
abstract：OBJECTIVE:Assess effect of right ventricular pacing (RVP) on left ventricular (LV) activation in heart failure patients with left bundle branch block (LBBB). BACKGROUND:LV activation during RVP is regarded as similar to LBBB; hence novel CRT algorithms may avoid RVP by adopting "fusion" pacing with intrinsic RBB-media...
journal_title：Journal of electrocardiology
pub_type： 临床试验,杂志文章
doi：10.1016/j.jelectrocard.2014.09.002
更新日期：2015-01-01 00:00:00
abstract：:Acute coronary syndromes due to involvement of the left main trunk usually present with subtotal occlusion and electrocardiographic pattern with predominant ST depression (non-ST-elevation myocardial infarction). The cases with complete occlusion frequently present an ST-elevation myocardial infarction pattern, but th...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2012.05.001
更新日期：2012-09-01 00:00:00
abstract：:Sources of error in averaging for late ventricular potentials include variations in the magnitude and timing of late potentials as well as variability in the temporal alignment of successive cardiac cycles during averaging. Since these errors can both attenuate high frequency signals and add artifactual components to ...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：
更新日期：1987-10-01 00:00:00
abstract：:The electrophysiologic actions of epinephrine (10(-9) M, 10(-8) M, and 10(-7) M) were evaluated in canine Purkinje fibers pretreated with the class III antiarrhythmic drugs clofilium (10(-7) M) or d,l-sotalol (10(-6) M). Clofilium and d,l-sotalol prolonged action potential duration at 50% and 90% of repolarization wit...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(97)80007-6
更新日期：1997-07-01 00:00:00
abstract：OBJECTIVE:We have previously used a 12-lead, signal-processed ECG to calculate blood potassium levels. We now assess the feasibility of doing so with a smartphone-enabled single lead, to permit remote monitoring. PATIENTS AND METHODS:Twenty-one hemodialysis patients held a smartphone equipped with inexpensive FDA-appr...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2017.06.008
更新日期：2017-01-01 00:00:00
abstract：:The purpose of this study was to describe the effects of gender and age on heart rate variability (HRV) in healthy volunteers (n = 111; 40 men and 71 women) and in persons after sudden cardiac arrest (SCA) (n = 95; 79 men and 16 women). Frequency-domain measurements and six time-domain measurements of HRV (SDANN, 24-h...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(94)80037-5
更新日期：1994-01-01 00:00:00
abstract：:One of the most important components of mechanoelectric coupling is stretch-activated channels, sarcolemmal channels that open upon mechanical stimuli. Uncovering the mechanisms by which stretch-activated channels contribute to ventricular arrhythmogenesis under a variety of pathologic conditions is hampered by the la...
journal_title：Journal of electrocardiology
pub_type： 杂志文章,评审
doi：10.1016/j.jelectrocard.2010.05.014
更新日期：2010-11-01 00:00:00
abstract：INTRODUCTION:The mechanisms of torsade de pointes tachycardia (TdP) are incompletely understood. We aimed to investigate the mechanisms underlying TdP tachycardia in patients with spontaneous high-degree atrioventricular block (AVB). METHODS AND RESULTS:This retrospective study reviewed old TdP recordings after ventri...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2019.05.007
更新日期：2019-01-01 00:00:00
abstract：:The goal of the 2007 PhysioNet/Computers in Cardiology Challenge was to try to establish how well it is possible to characterize the location and extent of old myocardial infarcts using electrocardiographic evidence supplemented by anatomical imaging information. A brief overview of the challenge and how different cha...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2008.07.022
更新日期：2008-11-01 00:00:00
abstract：AIM:The aim of this study was to investigate whether interventricular asynchrony (IVA) can be measured by electrocardiography. METHODS:Sixty-two patients (New York Heart Association heart failure functional class III: age, mean +/- SD: 64 +/- 9 years; ejection fraction, mean +/- SD: 24% +/- 8%; dilative cardiomyopathy...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2009.12.006
更新日期：2010-05-01 00:00:00
abstract：:Two cases of transient hemiblock occurring during the course of acute myocardial infarction are reported. The transient manifestation permits the accurate evaluation of the diagnostic features of the hemiblocks as modified by acute infarction. One case reflects the development of left bundle branch block due to bilate...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(78)80109-5
更新日期：1978-04-01 00:00:00
abstract：BACKGROUND:While J-waves were observed in healthy populations, variations in their reported incidence may be partly explicable by the ECG filter setting. METHODS:We obtained resting 12-lead ECG recordings in 665 consecutive patients and enrolled 112 (56 men, 56 women, mean age 59.3±16.1years) who manifested J-waves on...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/j.jelectrocard.2013.10.001
更新日期：2014-01-01 00:00:00
abstract：:This study was designed to clarify the mechanism of reperfusion arrhythmia. In the mongrel dogs, the left anterior descending coronary artery was occluded for 15 min and then the ligation was released. The dogs were divided into two groups: one was the control group, and the other the indomethacin group in which indom...
journal_title：Journal of electrocardiology
pub_type： 杂志文章
doi：10.1016/s0022-0736(82)81012-1
更新日期：1982-10-01 00:00:00
