Abstract:
:To show that cycle-length (CL) prolongation occurring at the onset of reentrant tachycardias may be associated with an increase in conduction time (CT), and to investigate the involvement of Na+ and Ca2+ channel activity, reentrant activity was induced by programmed stimulation in thin ventricular muscle slices with a central cryothermal lesion, as documented with 7 to 12 bipolar recordings. We studied the course of the CL measured in successive tachycardia beats, as well as the course of conduction times after abrupt transition from a pacing CL of 1,000 to 400 ms (pacing paradigm). The majority of the tachycardias displayed a dynamic behavior in which CL increased progressively, with an exponential rate constant of 37 +/- 35 beats (mean +/- SD), stabilizing at 325 +/- 67 ms after a total increase of 17 +/- 17 ms. In the pacing paradigm, CT was prolonged from 68 +/- 21 ms to 79 +/- 24 ms according to a biphasic course consisting of an abrupt increase in the first response to 400 ms, followed up by an exponential increase, stabilizing with a rate constant of 18 +/- 23 beats. Lidocaine 5 x 10(-5) mol/L induced an increase in steady-state CT, which was not further modified by adding verapamil 10(-5) mol/L. However, verapamil prolonged the rate constant of the exponential course by 60 +/- 40 beats. Thus, the onset dynamics of reentrant tachycardias share common features with the dynamic behavior of CT in the pacing paradigm, in which both Na+ channel activity and Ca2+-modulated cellular coupling appear to be involved.
journal_name
J Electrocardioljournal_title
Journal of electrocardiologyauthors
Lemarbre F,Vinet A,Vermeulen M,Cardinal Rdoi
10.1054/jelc.2000.18107keywords:
subject
Has Abstractpub_date
2000-10-01 00:00:00pages
349-60issue
4eissn
0022-0736issn
1532-8430pii
S0022073600259670journal_volume
33pub_type
杂志文章abstract:INTRODUCTION:This study is to investigate ventricular repolarization on electrocardiogram (ECG) in a pediatric population receiving methylphenidate (MPH), risperidone (RIS) and combined therapy. METHODS:A total of 215 patients between 6 and 12years with ADHD/conduct disorder receiving methylphenidate, risperidone and ...
journal_title:Journal of electrocardiology
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更新日期:2017-01-01 00:00:00
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journal_title:Journal of electrocardiology
pub_type: 杂志文章
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abstract:INTRODUCTION:Measures of heart rate variability (HRV) can be divided in time domain and frequency domain parameters. It is frequently ignored that estimation of frequency-domain parameters is a 2-step procedure where statistical error from the first step (spectral estimation) is neglected in subsequent analyses. METHO...
journal_title:Journal of electrocardiology
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abstract::Vagally mediated paroxysmal atrial fibrillation is typically described to occur in otherwise healthy young-to-middle aged males during periods of high vagal tone. We report a case of cardioinhibitory type neurocardiogenic syncope associated with atrial fibrillation in an elderly female during episodes of nausea. This ...
journal_title:Journal of electrocardiology
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journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/0022-0736(89)90082-4
更新日期:1989-04-01 00:00:00
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journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2010.11.012
更新日期:2011-03-01 00:00:00
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pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2020.09.001
更新日期:2020-01-01 00:00:00
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journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2011.03.007
更新日期:2011-11-01 00:00:00
abstract:BACKGROUND:Several novel ECG markers are proposed to predict the risk of sudden cardiac death in several clinical conditions in the recent years. However, little is known about the association of pericardial fat or obesity with these markers. OBJECTIVES:To assess the possible relationship between pericardial fat volum...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2018.03.008
更新日期:2018-01-01 00:00:00
abstract::Quantitative analysis of ST-segment deviations (STdev) and their resolution by treatment (STR; calculated from a combined sum of STdev in multiple leads) are used in trials on reperfusion for myocardial infarction (MI). Unreadable or unavailable electrocardiogram (ECG) leads are a common reason for exclusion, decreasi...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(03)00030-x
更新日期:2003-07-01 00:00:00
abstract:BACKGROUND:Coronary artery disease and myocardial ischemia cause substantial morbidity and mortality. While ischemia is traditionally diagnosed on the 12-lead electrocardiogram (ECG) by shifts in the ST segment, electrical changes are also produced within the QRS complex during depolarization of ischemic ventricular ti...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2014.09.005
更新日期:2015-01-01 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::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
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journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2016.03.014
更新日期:2016-05-01 00:00:00
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journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2010.02.003
更新日期:2010-05-01 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::A method has been developed for establishing a "University Without Walls" for the purpose of studying the relationship between electrocardiographic estimation and magnetic resonance imaging measurements of myocardial infarct size. The research team includes faculty and students from 4 medical centers, with expertise e...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1054/jelc.2001.28810
更新日期:2001-01-01 00:00:00
abstract::In patients presenting with signs and symptoms of an acute coronary syndrome (ACS) the combination of multilead ST depression and ST elevation in lead aVR, the electrocardiographic "aVR sign," has been associated with severe left main coronary artery stenosis or diffuse coronary artery disease and a high risk of death...
journal_title:Journal of electrocardiology
pub_type: 杂志文章,评审
doi:10.1016/j.jelectrocard.2019.07.014
更新日期:2019-01-01 00:00:00
abstract::A comparison was made of the electrophysiological properties of the fibers between the previously reported conduction pathways from the left atrium to the right atrium and to the ventricle (left A-V ring pathways) and the ordinary atrial muscle, using perfused isolated rabbit hearts. Each fiber within these pathways s...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(80)80006-9
更新日期:1980-01-01 00:00:00
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journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2006.06.004
更新日期:2008-01-01 00:00:00
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journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2009.07.019
更新日期:2009-11-01 00:00:00
abstract::The Brugada syndrome (BS) accounts for approximately 20% of cases of sudden cardiac death in patients with structurally normal hearts. The electrophysiologic basis for ST-segment elevation in the precordial electrocardiogram (ECG) leads that characterize the Brugada phenotype and its strong linkage to ventricular tach...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/j.jelectrocard.2010.07.008
更新日期:2010-09-01 00:00:00
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journal_title:Journal of electrocardiology
pub_type: 临床试验,杂志文章
doi:10.1016/j.jelectrocard.2011.08.012
更新日期:2012-05-01 00:00:00
abstract::Under healthy conditions, the normal cardiac (sinus) interbeat interval fluctuates in a complex manner. Quantitative analysis using techniques adapted from statistical physics reveals the presence of long-range power-law correlations extending over thousands of heartbeats. This scale-invariant (fractal) behavior sugge...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(95)80017-4
更新日期:1995-01-01 00:00:00
abstract::One-to-two atrioventricular conduction, ie, the double response to a single sinus or atrial impulse, resulting in two QRS complexes for one P wave, is a rare manifestation of dual atrioventricular (AV) nodal pathways. This report describes the case of a 61-year-old woman with continuous episodes of supraventricular ta...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(99)90005-5
更新日期:1999-10-01 00:00:00
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journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(79)80057-6
更新日期:1979-07-01 00:00:00
abstract::Computer analysis of electrocardiograms (ECGs) provides a large amount of ECG measurement data, which may be used for diagnostic classification and storage in ECG databases. Until now, neither error limits for ECG measurements have been specified nor has their influence on diagnostic statements been systematically inv...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(96)80022-7
更新日期:1996-01-01 00:00:00
abstract::In this study it is analyzed by linear and non-linear methods, how the control of instantaneous heart rate (IHR) develops in infants in quiet and active sleep. Ten healthy and term newborns were studied during their first half year of life. Low (LF) and high frequency power (HF) of the spectrum, and the largest Lyapun...
journal_title:Journal of electrocardiology
pub_type: 杂志文章
doi:10.1016/s0022-0736(05)80064-0
更新日期:1995-10-01 00:00:00