Electrophysiological properties of right heart and atrioventricular conducting system in patients with alcoholic cardiomyopathy.

Abstract

In 20 men with alcoholic cardiomyopathy, right atrial and right ventricular monophasic action potential, relative repolarization rate of phase 3 and effective refractory period were studied, as well as atrioventricular conduction properties. The duration of right atrial monophasic action potential and effective refractory period recorded in the middle of the right atrium was shorter compared to control patients while the right atrial relative repolarization rate phase 3 was unchanged. In 5 patients with atrial fibrillation, after conversion to sinus rhythm, great variations were found between right atrial monophasic action potential duration at 90% and 50% repolarization, atrial effective refractory period, and right atrial relative repolarization rate of phase 3 recorded in 3 different sites of the right atrium. The right ventricular monophasic action potential duration at 90% repolarization was longer, while right ventricular monophasic action potential duration at 50% and right ventricular relative repolarization rate of phase 3 were shorter in alcoholics compared with the control group. The greatest differences between right ventricular monophasic action potential duration and ventricular effective refractory period obtained in 3 different sites of the right ventricle was observed in alcoholics with frequent ventricular premature beats. The alcoholic patients showed PR prolongation in 35% of cases and intraventricular conduction defects in 50% of cases. In 11 patients His bundle electrograms and atrial pacing showed latent conduction disturbances proximal and distal to the bundle of His.