Rate-related left bundle branch block with chest pain and normal coronary arteriograms treated by exercise training.

A clinical observation of chest pain associated with the onset of rate-related left bundle branch block has been described in patients with normal coronary arteriograms. The authors used standard cardiac rehabilitation techniques for exercise training in a 47-year-old woman with these manifestations. Serial treadmill tests revealed that during the course of 3 months of exercise training, the heart rate at onset of LBBB gradually rose from 133 to 175 beats per minute, and she no longer developed symptoms during her routine daily activities or exercises. Exercise training was a successful nonpharmacologic strategy that delayed the onset of rate-related LBBB and chest pain in this patient and avoided the need for beta blocker therapy.