Dataset Information

Spatial Heterogeneity of Cx43 is an Arrhythmogenic Substrate of Polymorphic Ventricular Tachycardias during Compensated Cardiac Hypertrophy in Rats.

ABSTRACT:

Background

Ventricular remodeling increases the propensity of ventricular tachyarrhythmias and sudden death in patients. We studied the mechanism underlying these fatal arrhythmias, electrical and structural cardiac remodeling, as well as arrhythmogeneity during early, compensated hypertrophy in a rat model of chronic pressure overload.

Methods

Twenty-six Wistar rats were subjected to transverse aortic constriction (TAC) (n?=?13) or sham operation (n?=?13). Four weeks postoperative, echo- and electrocardiography was performed. Epicardial (208 or 455 sites) and transmural (30 sites) ventricular activation mapping was performed on Langendorff perfused hearts. Subsequently, hearts were processed for (immuno)histological and molecular analyses.

Results

TAC rats showed significant hypertrophy with preserved left ventricular (LV) function. Epicardial conduction velocity (CV) was similar, but more dispersed in TAC. Transmural CV was slowed in TAC (37.6?±?2.9?cm s(-1)) compared to sham (58.5?±?3.9?cm s(-1); P?ConclusionIn TAC rats with compensated cardiac hypertrophy, dispersion of conduction correlated to arrhythmogenesis, an increased heterogeneity of Cx43, and a partial substitution with non-phosphorylated Cx43. These alterations may result in the increased vulnerability to polymorphic VTs.

SUBMITTER: Boulaksil M

PROVIDER: S-EPMC4773605 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Publications

Spatial Heterogeneity of Cx43 is an Arrhythmogenic Substrate of Polymorphic Ventricular Tachycardias during Compensated Cardiac Hypertrophy in Rats.

Boulaksil Mohamed M Bierhuizen Marti F A MF Engelen Markus A MA Stein Mèra M Kok Bart J M BJ van Amersfoorth Shirley C M SC Vos Marc A MA van Rijen Harold V M HV de Bakker Jacques M T JM van Veen Toon A B TA

Frontiers in cardiovascular medicine 20160302

<h4>Background</h4>Ventricular remodeling increases the propensity of ventricular tachyarrhythmias and sudden death in patients. We studied the mechanism underlying these fatal arrhythmias, electrical and structural cardiac remodeling, as well as arrhythmogeneity during early, compensated hypertrophy in a rat model of chronic pressure overload.<h4>Methods</h4>Twenty-six Wistar rats were subjected to transverse aortic constriction (TAC) (n = 13) or sham operation (n = 13). Four weeks postoperativ ...[more]

PMID: 26973841

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Dataset Information

Spatial Heterogeneity of Cx43 is an Arrhythmogenic Substrate of Polymorphic Ventricular Tachycardias during Compensated Cardiac Hypertrophy in Rats.

Background

Methods

Results

Publications

Spatial Heterogeneity of Cx43 is an Arrhythmogenic Substrate of Polymorphic Ventricular Tachycardias during Compensated Cardiac Hypertrophy in Rats.

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