Regression of a "Tachycardia-Induced Cardiomyopathy" aftet Radiofrequency A-V Node Ablation

pp 357-360

Abstract

The existence of a cardiomyopathy-like syndrome related with abnormally high and persistent heart rates has been reported in several articles. Appropriate control of heart rates frequently results in marked hemodynamic improvement with normalization of ventricular function and regression of cardiac dilatation. Two male patients (aged67 and75 years old) were admitted because of incessant supraventricular tachycardias and signs of left ventricular dysfunction. The mechanism of the tachyarrhythmia determined at the electrophysiologic study was an intra atrial reentry in case 1. Three types of atrial tachycardias were documented in case 2. Both patients underwent an AV node radiofrequency ablation procedure and had a permanent rate responsive pacemaker implanted. They were followed with evaluation of their functional class and echocardiographic parameters. Ejection fraction was also evaluated in case 1. After the ablation procedure a progressive reduction of left ventricular diastolic and systolic diameters and improvement in functional class (NYHA) occurred in both patients. An increase in the ejection fraction of the left ventricle was observed in case 1. Detection of tachycardia-induced cardiomyopathy may lead to the early indication of recently developed therapeutic procedures such as radiofrequency ablation in order to avoid the deletereous consequences of persistently high heart rates.