His Bundle Pacing Versus Coronary Sinus Pacing for Cardiac Resynchronization Therapy

The goal of this study is to compare the effectiveness of pacing from a physiologic His bundle (HB) lead position versus with the standard coronary sinus (CS) lead position in subjects with heart failure undergoing cardiac resynchronization therapy (CRT). While placement of left ventricular leads via the coronary sinus has anatomic limitations, we hypothesis that the achievement of QRS narrowing with His bundle capture will be superior for improving systolic function by echocardiographic indices (ejection fraction and strain) and quality of life and decreased rehospitalization and mortality.