Heart failure has become one of the major epidemics of the modern era. Despite optimal standard drug therapy, the prognosis of patients with heart failure remains poor. It has been noted that 15% of all HF patients and 30% of those with NYHA class III and IV HF have intraventricular conduction delay, with a QRS duration >120 ms, most commonly manifested as LBBB. These electrical disturbances result in LV dyssynchrony, seen as a paradoxical septal wall motion activity, suboptimal ventricular filling and mitral regurgitation; thus further compromising an already dysfunctioning left ventricle. Ventricular dyssynchrony has been associated with increased mortality in patients with heart failure.