Successful Catheter Ablation as a Substitute for Cardiac Resynchronization Therapy in Patient with an Accessory Pathway-induced Cardiomyopathy.

A 50-year-old man presented with exertional dyspnea and orthopnea. An electrocardiogram showed a delta wave and a wide QRS complex, similar to left bundle branch block. Cardiac echocardiography revealed diffuse severe hypokinesis and dyssynchrony. The patient was diagnosed with congestive heart failure. We considered that the patient's condition was caused by an accessory pathway-induced cardiomyopathy after heart failure compensation with guideline-oriented medical therapy. We therefore performed catheter ablation for right-sided pre-excitation syndrome as cardiac resynchronization therapy. The left ventricular dyssynchrony was resolved immediately after the procedure, and the patient's ventricular contraction improved, with a reduced cardiac volume at 6 months after the procedure-thus suggesting that the accessory pathway had affected the patient's cardiac function.