Stimulation cardiaque et insuffisance cardiaque

Abstract

Cardiac activation and heart failure. Dilated cardiomyopathies are frequently associated with atrioventricular and intra ventricular conduction disorders. Such conduction disorders modify the cardiac activation sequence and impair left ventricular systolic and diastolic function. The aim of pacing in dilated cardiomyopathy is to restore a cardiac activation sequence as normal as possible. Conventional dual-chamber pacing was first proposed to treat drug-refractory heart failure but was soon replaced by multisite biventricular pacing. The aim of biventricular pacing is to correct intraventricular asynchrony by pacing the two ventricles simultaneously. Acute studies have shown that biventricular pacing could improve hemodynamic parameters in patients with dilated cardiomyopathy and severe intraventricular conduction disorders. More recently, chronic studies demonstrated a significant improvement in exercise tolerance and quality of life with biventricular pacing in patients with drug-refractory heart failure and with intraventricular conduction disorders. To safely pace the left ventricle specific materials and tools had to be developed. With those developments, biventricular pacing is now a feasible and safe technique. Regarding the results of several clinical studies, biventricular pacing could now be proposed to treat patients with drug-refractory heart failure in the setting of chronic left ventricular systolic dysfunction and with major intraventricular conduction disorders.