Cardiac resynchronization therapy for treatment of chronic heart failure

Cardiac resynchronization therapy (CRT) by means of biventricular pacing is a fairly new procedure that has recently been approved by the United States Food and Drug Administration. Many promising studies have been published that suggest CRT improves patient quality of life (based on the Minnesota Living with Heart Failure Quality of Life Questionnaire), increases distance walked in 6 minutes, improves oxygen uptake, lowers New York Heart Association classification, decreases QRS duration, increases left ventricular ejection fraction, and increases peak oxygen consumption. These studies include the Multisite Stimulation in Cardiomyopathies (MUSTIC), the Multicenter InSync Randomized Clinical Evaluation (MIRACLE), the Pacing Therapy for Congestive Heart Failure (PATH-CHF) multicenter trial, the Medtronic Inc. InSync study, the Ventak CHF/Contak CD study, Vigor CHF and a small study conducted by Alonso and colleagues. There are also a number of studies that are still being conducted, such as the COMPANION trial, which will provide further insight into the effectiveness of cardiac resynchronization therapy.