PMID: 9180130Jun 1, 1997Paper

Electrophysiologic effects of sodium channel blockade on anisotropic conduction and conduction block in canine myocardium: preferential slowing of longitudinal conduction by flecainide versus disopyramide or lidocaine

Journal of the American College of Cardiology
T KondoH Tomoike

Abstract

The purpose of this study was to determine the effects of sodium channel blockade on anisotropic excitation propagation in the intact canine left ventricle. Anisotropic ventricular conduction- electric conductivity dependent on the myocardial fiber direction-is one of the important mechanisms of ventricular arrhythmia. However, the effects of sodium channel blockade, especially the differential effect of a subclass of this agent, on the anisotropic properties remain unknown. In 28 anesthetized, open chest dogs, a small cannula was inserted into the left anterior descending coronary artery. Saline (control), disopyramide, lidocaine or flecainide was infused selectively into the cannula. An array of 64 epicardial electrodes was placed on the anterior surface of the ventricle. Activation time (AT) was measured along the longitudinal (L) and transverse (T) directions. High dose flecainide (100 microg/kg body weight per min) delayed the AT along the L direction markedly (mean [+/-SE] 227 +/- 38%, p < 0.02) and mildly (121 +/- 10%, p < 0.02) along the T direction in regular beats (p < 0.007, L vs. T). Lidocaine and disopyramide did not show direction-dependent prolongation of the AT on regular beats. When examined on premature beats,...Continue Reading

References

Jan 1, 1990·Annals of the New York Academy of Sciences·A L WitB Waldecker
Jul 1, 1985·The American Journal of Cardiology·D C Harrison
Mar 1, 1988·Japanese Circulation Journal·I Kodama, J Toyama
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May 1, 1995·The American Journal of Emergency Medicine·D M SalernoP R Pentel

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Citations

Dec 18, 1998·Japanese Circulation Journal·T WatanabeH Tomoike
Jul 11, 2000·Japanese Heart Journal·T WatanabeH Tomoike
Mar 8, 2003·American Journal of Physiology. Heart and Circulatory Physiology·J Jason SimsNicholas A Wiegert
Sep 14, 1999·The American Journal of Physiology·T WatanabeH Tomoike
Feb 7, 2012·American Journal of Physiology. Heart and Circulatory Physiology·Leroy L CooperGideon Koren

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