Resynchronizing Ventricular Contraction in Heart Failure

Abstract

One quarter to one third of patients with congestive heart failure have some form of intraventricular conduction abnormality that is manifested as an increased QRS duration on the electrocardiogram.^1,2 The most common pattern is left bundle-branch block. In patients with left bundle-branch block, electrical activation of the lateral aspect of the left ventricle can be substantially delayed in relation to that of the right ventricle and interventricular septum. Dyssynchronous electrical activation results in dyssynchronous contraction, which is mechanically inefficient. Regional myocardial workload is distributed unequally, and regional myocardial blood flow and metabolism may be altered. As a result, the . . .