Combination therapy with corticosteroid and mycophenolate mofetil in a case of refractory cardiac sarcoidosis

Management of cardiac sarcoidosis (CS) can be challenging. The first-line therapy for this condition is corticosteroids, but other immunosuppressive agents are sometimes co-administered to reduce the dosage of corticosteroid and to thereby avoid steroid-induced adverse effects or to increase its therapeutic efficacy. Mycophenolate mofetil (MMF) is a prodrug of mycophenolic acid, an inhibitor of inosine monophosphate dehydrogenase that acts more selectively on T and B lymphocytes when compared with azathioprine. A 40-year-old man was diagnosed with CS after presenting with ventricular fibrillation. His left ventricular ejection fraction was severely reduced (30%), and cardiac positron emission tomography (PET) showed abnormal uptake of ¹⁸F-fluorodeoxyglucose. A cardioverter-defibrillator was implanted and prednisolone (30 mg/day) was administered. He was re-admitted with recurrent sustained ventricular tachycardia and a positive PET finding despite a 5-month course of prednisolone, and MMF (1000 mg/day) was administered. Six months later, he had not required re-hospitalization for heart failure or arrhythmia. We conclude that combination therapy with MMF and corticosteroids is useful for refractory CS. .