Effects of Multisite Biventricular Pacing in Patients with Heart Failure and Intraventricular Conduction Delay

The aging of the population has made chronic heart failure an increasingly important health problem. 1 It is the leading medical cause of hospitalization, and its economic cost continues to increase. Despite important therapeutic advances with angiotensin-converting–enzyme (ACE) inhibitors 2 , 3 or angiotensin II–receptor blockers, 4 beta-blockers, 5 and spironolactone, 6 the prognosis of patients with chronic heart failure remains poor. The benefit of medical treatment is probably short-lived, 7 , 8 merely delaying the inevitable progression to heart failure that is refractory to drug treatment. As the disorder progresses, the well-being and exercise tolerance of patients deteriorate dramatically, and the rates of hospitalization increase. Nonpharmacologic therapies . . .