Heart failure was a major and increasing public healthproblem, with an almost “epidemic” increase in thenumber of patients. Despite recent advances inpharmacotherapy, the prognosis remains poor. Cardiacresynchronization therapy (CRT), by pacing right and leftventricles, has been proved to improve symptoms andreduce mortality for heart failure patients with cardiacdyssynchrony. However, 20% to 30% of patients didnot respond to CRT. The good cardiac synchronicitybefore CRT and the remaining atrioventricular, inter-and Heart failure was a major and increasing public healthproblem, with an almost “epidemic ” increase in then ofmber of patients. Despite recent advances inpharmacotherapy, the prognosis remains poor. Cardiac resynchronization therapy (CRT), by pacing right and leftventricles, has been proved to improve symptoms andreduce mortality for heart failure patients with cardiacdyssynchrony. However, 20% to 30% of patients didnot respond to CRT. The good cardiac synchronicity before CRT and the remaining atrioventricular, inter-and