Tachycardia-induced cardiomyopathy could present with acute heart failure, and an electrophysiology study with ablation was proven effective treatment in these circumstances. However, an invasive emergency procedure could always carry an increasing risk of complication, which could be devastating in a failing heart. We reported a case with incessant refractory supraventricular tachycardia and the ablation therapy complicated by ventricular fibrillation. Despite such a mishap, we managed to eliminate the accessory pathway as the cause of the tachycardia, and the patient was successfully treated with percutaneous cardiopulmonary support.