Abstract:
INTRODUCTION:Regional dispersions of repolarization (DOR) are arrhythmogenic perturbations that are closely associated with reentry. However, the characteristics of DOR have not been well defined or adequately analyzed because previous algorithms did not take into account spatial heterogeneities of action potential durations (APDs). Earlier simulations proposed that pathologic conditions enhance DOR by decreasing electrical coupling between cells, thereby unmasking differences in cellular repolarization between neighboring cells. Optical mapping indicated that gradients of APD and DOR are associated with fiber structure and are largely independent of activation. We developed an approach to quantitatively characterize APD gradients and DOR to determine how they are influenced by tissue anisotropy and cell coupling during diverse arrhythmogenic insults such as hypoxia and hypothermia. METHODS AND RESULTS:Voltage-sensitive dyes were used to map APs from 124 sites on the epicardium of Langendorff-perfused guinea pig hearts during (1) cycles of hypoxia and reoxygenation and (2) after 30 minutes of hypothermia (32 degrees to 25 degrees C). We introduce an approach to quantitate DOR by analyzing two-dimensional spatial autocorrelation of APDs along directions perpendicular and parallel to the longitudinal axis of epicardial fibers. A spatial correlation length L was derived as a statistical measure of DOR. It corresponds to the distance over which APDs had comparable values, where L is inversely related to DOR. Hypoxia (30 min) caused a negligible decrease in longitudinal thetaL (from 0.530 +/- 0.138 to 0.478 +/- 0.052 m/sec) and transverse thetaT (from 0.225 +/- 0.034 to 0.204 +/- 0.021 m/sec) conduction velocities and did not alter thetaL/thetaT or activation patterns. In paced hearts (cycle length [CL] = 300 msec), hypoxia decreased APDs (123 +/- 18.2 to 46 +/- 0.6 msec; P < 0.001) within 10 to 15 minutes and enhanced DOR, as indicated by reductions of L from 1.8 +/- 0.9 to 1.1 +/- 0.5 mm (P < 0.005). Hypothermia caused marked reductions of thetaL (0.53 +/- 0.138 to 0.298 +/- 0.104 m/sec) and thetaT (0.225 +/- 0.034 to 0.138 +/- 0.027 m/sec), increased APDs (128 +/- 4.4 to 148 +/- 14.5 msec), and reduced L from 2.0 +/- 0.3 to 1.3 +/- 0.6 mm (P < 0.05). L decreased with increased time of hypoxia and recovered upon reoxygenation. Hypoxia and hypothermia reduced L measured along the longitudinal (L(L)) and transverse (L(T)) axes of cardiac fibers while the ratio of L(L)/L(T) remained constant. CONCLUSION:Conventional indexes of DOR (i.e., APD "range" or "standard deviation," evaluated with extracellular electrodes) did not convey the spatial inhomogeneities of repolarization revealed by L. Spatial autocorrelation analysis provides a statistically significant measurement of DOR, which can take into account intrinsic heterogeneities of APDs and fiber orientation. The data show that hypoxia and hypothermia produce reductions of L, even though they have different effects on mean APD and conduction velocity. The preservation of a constant L(L)/L(T) ratio during hypoxia and hypothermia, despite large reductions in L, is consistent with a mechanism in which reduced cell-to-cell coupling unmasks intrinsic dispersions of APD and reduces L(L) and L(T) by the same factor. Thus, the spatial autocorrelation of APDs provides a sensitive index of DOR under normal and arrhythmogenic conditions. It incorporates the anisotropic nature of the myocardium and therefore is preferable to conventional indexes of DOR.
journal_name
J Cardiovasc Electrophysioljournal_title
Journal of cardiovascular electrophysiologyauthors
Salama G,Kanai AJ,Huang D,Efimov IR,Girouard SD,Rosenbaum DSdoi
10.1111/j.1540-8167.1998.tb00897.xsubject
Has Abstractpub_date
1998-02-01 00:00:00pages
164-83issue
2eissn
1045-3873issn
1540-8167journal_volume
9pub_type
杂志文章abstract:INTRODUCTION:Previous studies have underscored the importance of the interpulmonary isthmus in the initiation and maintenance of atrial fibrillation (AF). The efficacy of additional radiofrequency energy delivery in the interpulmonary isthmus following pulmonary vein antral isolation (PVAI) was investigated. METHODS A...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章,随机对照试验
doi:10.1111/jce.12399
更新日期:2014-07-01 00:00:00
abstract::Due to the growing number of patients treated with cardiac implantable electronic devices (CIEDs) there is an increased need for lead management, evaluation, and extraction. While CIED lead extraction has many indications, a consistent approach to preprocedural planning should be applied in all cases, including a thor...
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更新日期:2020-07-01 00:00:00
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journal_title:Journal of cardiovascular electrophysiology
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doi:10.1046/j.1540-8167.2001.01010.x
更新日期:2001-09-01 00:00:00
abstract:INTRODUCTION:Longer observational time and adenosine challenge have proven to be able to detect pulmonary vein (PV) reconnections. The aim of this study was to assess incidence of spontaneous and adenosine-induced PV reconnection after ablation with second-generation cryoballoon (CB-Adv). METHODS AND RESULTS:Fifty con...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1111/jce.12421
更新日期:2014-08-01 00:00:00
abstract:INTRODUCTION:The success of pulmonary vein isolation (PVI) for atrial fibrillation (AF) may be improved if stable AF sources identified by Focal Impulse and Rotor Mapping (FIRM) are also eliminated. The long-term results of this approach are unclear outside the centers where FIRM was developed; thus, we assessed outcom...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章,多中心研究
doi:10.1111/jce.12474
更新日期:2014-09-01 00:00:00
abstract::The evidence that antiarrhythmic compounds that act by slowing conduction velocity increase mortality in patients with cardiac disease is now compelling. Emphasis is now shifting to agents that act by lengthening repolarization and have additional antiadrenergic properties. There is preliminary evidence that pure Clas...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章,评审
doi:10.1111/j.1540-8167.1995.tb00365.x
更新日期:1995-10-01 00:00:00
abstract:INTRODUCTION:Radiofrequency (RF) ablation of ventricular tachycardia (VT) late after myocardial infarction may be difficult due to characteristics of the infarct containing the reentry circuit. RF lesions in these infarcts in humans have not been characterized. METHODS AND RESULTS:Catheter mapping and ablation of VT o...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1111/j.1540-8167.1995.tb00439.x
更新日期:1995-08-01 00:00:00
abstract:INTRODUCTION:Recent work has suggested a role for organized sources in sustaining ventricular fibrillation (VF). We assessed whether ablation of rotor substrate could modulate VF inducibility in canines, and used this proof-of-concept as a foundation to suppress antiarrhythmic drug-refractory clinical VF in a patient w...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1111/jce.12753
更新日期:2015-10-01 00:00:00
abstract::The search for a mechanism to explain atrial fibrillation (AF) has lasted for over a century and continues. Significant progress in understanding this arrhythmia accelerated with the era of operative treatment of this arrhythmia and intensified with the advent of catheter ablation. Through considerable trial and some ...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 历史文章,杂志文章
doi:10.1111/j.1540-8167.2006.00738.x
更新日期:2007-04-01 00:00:00
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pub_type: 临床试验,杂志文章
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journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1111/j.1540-8167.2000.tb00029.x
更新日期:2000-06-01 00:00:00
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journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1111/j.1540-8167.2008.01378.x
更新日期:2009-06-01 00:00:00
abstract:UNLABELLED:Atrial Defibrillator. INTRODUCTION:The atrial defibrillator empowers patients to cardiovert themselves from atrial arrhythmias at a time that is socially and physically acceptable, thereby preventing hospitalization. The long-term psychosocial effects of repeated use of the patient-activated atrial defibril...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 临床试验,杂志文章
doi:10.1046/j.1540-8167.2003.03108.x
更新日期:2003-08-01 00:00:00
abstract::We describe the case of 2-year-old baby with compound heterozygosity for paternal and maternal alleles mutation of α-subunit of the cardiac sodium channel (SCN5A), sinus node dysfunction, atrial flutter recurrences, and drug induced long-QT syndrome. In this setting, we chose at first to perform linear ablation of cav...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1111/jce.12570
更新日期:2015-03-01 00:00:00
abstract:INTRODUCTION:Several single-center short-term studies have demonstrated the feasibility, safety, and positive clinical outcomes of permanent His bundle pacing (HBP). We performed a retrospective study to evaluate long-term technical and safety performances of HBP in a large population of pacemaker patients from two dif...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章,多中心研究
doi:10.1111/jce.14063
更新日期:2019-09-01 00:00:00
abstract:INTRODUCTION:In isolated rabbit hearts, repetitive endocardial focal discharges (REFDs) were consistently observed during ventricular fibrillation (VF) with prolonged (>5 minutes) global ischemia (GI). We hypothesized that BAPTA-AM, a calcium chelator, can suppress these REFDs. METHODS AND RESULTS:Using a two-camera o...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1111/j.1540-8167.2011.02067.x
更新日期:2011-10-01 00:00:00
abstract:INTRODUCTION:Fusion of left ventricular pacing with intrinsic conduction provides superior resynchronization compared to biventricular pacing. His bundle pacing (HBP) preserves intrinsic conduction and allows for constant fusion with left ventricular pacing. This study evaluated sequential His bundle and left ventricul...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1111/jce.14674
更新日期:2020-09-01 00:00:00
abstract:INTRODUCTION:Catheter ablation can terminate persistent atrial fibrillation (AF). However, atrial tachycardia (AT) often arises after termination of AF. METHODS AND RESULTS:Of 215 patients who underwent index stepwise ablation for persistent AF, 141 (66%) patients (64 ± 9 years) in whom AF terminated during the ablati...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1111/jce.13187
更新日期:2017-05-01 00:00:00
abstract::Catheter ablation for ventricular tachycardia (VT) is becoming an essential component of the successful management of patients with structural heart disease and refractory ventricular arrhythmias. Despite detailed mapping and ablation from the endocardium, nearly a third of VT circuits remain inaccessible. Pericardial...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章,评审
doi:10.1111/j.1540-8167.2008.01427.x
更新日期:2009-06-01 00:00:00
abstract::The incidence of atrial fibrillation (AF) in Brugada syndrome (BrS) has been reported at between 9% and 53% by different series, but the true prevalence is unknown. However, AF may be the presenting feature in some patients. The underlying mechanisms for AF may be a combination of multiple factors, genetic or acquired...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章,评审
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journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1046/j.1540.8167.90317.x
更新日期:2003-10-01 00:00:00
abstract:INTRODUCTION:Atrial fibrillation (AF) is the most frequent arrhythmia seen in clinical practice. Until recently, antiarrhythmic medications have been the only commonly employed treatment for maintaining sinus rhythm. However, antiarrhythmic medications have a modest long-term efficacy and the potential for serious side...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章,多中心研究,评审
doi:10.1111/j.1540-8167.2008.01285.x
更新日期:2009-02-01 00:00:00
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journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1111/jce.12140
更新日期:2013-08-01 00:00:00
abstract:INTRODUCTION:The degree of organization in ventricular fibrillation (VF) is not known. As an objective measurement of spatial order, spatial correlation functions and their characteristic lengths were estimated from epicardial electrograms of pigs in VF. METHODS AND RESULTS:VF was induced by premature stimulation in f...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1111/j.1540-8167.1993.tb01242.x
更新日期:1993-10-01 00:00:00
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journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1111/j.1540-8167.2009.01672.x
更新日期:2010-06-01 00:00:00
abstract:INTRODUCTION:Accurate analysis of the arrhythmia substrate is important for successful radiofrequency ablation of sustained ventricular tachycardia (VT) after myocardial infarction (MI). METHODS AND RESULTS:A multielectrode "basket" catheter capable of endocardial recording and pacing was inserted percutaneously into ...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1111/j.1540-8167.1999.tb00209.x
更新日期:1999-11-01 00:00:00
abstract:UNLABELLED:Amiodarone/Silymarin Treatment for Sustained Atrial Flutter. INTRODUCTION:Because amiodarone generates free radicals that may mediate amiodarone's toxicity, simultaneous therapy with an antioxidant might be beneficial if the antioxidant did not impair amiodarone's antiarrhythmic action. We tested whether si...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1046/j.1540-8167.2003.02446.x
更新日期:2003-08-01 00:00:00
abstract:INTRODUCTION:EnSite NavX (NavX) is a novel mapping and navigation system that allows visualization of conventional catheters for diagnostic and ablative purposes and uses them to create a three-dimensional (3D) geometry of the heart. NavX is particularly suitable for ablation procedures utilizing an anatomic approach, ...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1046/j.1540-8167.2004.04064.x
更新日期:2004-10-01 00:00:00
abstract::Atrial fibrillation and heart failure are increasing in prevalence, and frequently coexist. Despite the desire to restore sinus rhythm in heart failure patients, large studies comparing rate control to pharmacologic rhythm control have failed to show superiority of either approach. This may in part be due to the ineff...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章,评审
doi:10.1111/jce.13497
更新日期:2018-07-01 00:00:00
abstract:BACKGROUND:Data comparing dabigatran with rivaroxaban regarding the resolution of left atrial/left atrial appendage (LA/LAA) thrombus in patients with nonvalvular atrial fibrillation (AF) are scarce. This study aimed to compare the efficacy and safety of dabigatran vs rivaroxaban regarding the resolution of LA/LAA thro...
journal_title:Journal of cardiovascular electrophysiology
pub_type: 杂志文章
doi:10.1111/jce.14365
更新日期:2020-03-01 00:00:00