Heart-transplant and mono-amine oxidase inhibitors

A case of anesthesia for a heart-transplant operation on a patient on mono-amine oxidase inhibitors (M.A.O.I.) is reported. This 63-year-old farmer was in end-stage cardiac failure due to familial cardiomyopathy. For 24 hours before surgery, he was on a dobutamine infusion (3 mcg/kg/min). He had been taking nialamide (100 mg/day) for 8 years for reactional depression and had not stopped it, despite advice. Anesthesia was induced with etomidate and succinylcholine, and maintained with fentanyl (25 mcg/kg/min) and pancuronium. Cardio-vascular stability was maintained during induction and first stage of surgery, up to cardectomy. Graft ischemia was 188 minutes. Successful defibrillation occurred after verapamil 3 mg. Weaning from C.P.B. was easy with dopamine (5 mcg/kg/min) and isoprenaline (0.01 mcg/kg/min). Post-operatively, on day 1, hypertension appeared and needed a nitroprusside infusion. On day 3, the patient needed another anesthetic for removal of pericardial clots, without problems. He remained very confused and disorientated during all his stay in hospital, but improved greatly with a neuroleptic. He left the hospital on day 28 in a good shape, with an anxiolytic, captopril and immunosuppressors. One month later, he was back on nialamide. The pharmacology of the M.A.O.I. is reviewed and their interactions with anesthesia are discussed as well as the use of inotropes. In this case, the denervated heart-graft, free from M.A.O. inhibition, behaved normally when transplanted in a chronically M.A.O.I. treated recipient.