Cibenzoline intoxication necessitating implantation of a biventricular assist system in a patient with severe cardiomyopathy.

A 46-year-old man was admitted to our hospital in cardiogenic shock. A BVS-5000s biventricular assist system (BVAS) was implanted after establishment of extracorporeal membrane oxygenation. At admission, the patient's serum cibenzoline level was extremely high, 6336 ng/ml. As the cibenzoline level dropped, his cardiac function recovered gradually. The patient was weaned from the right ventricular assist system after pulmonary vein isolation ablation for atrial tachycardia on postoperative day 17, and from left ventricular assist system on day 33. There is the first report of a patient with severe cardiomyopathy induced by cibenzoline intoxication that necessitated implantation of a BVAS. This case illustrates the importance of checking cibenzoline levels regularly in patients receiving long-term therapy with this drug so as to avoid the possibility of severe drug-induced heart failure.