Giant Cell Myocarditis: Excellent Outcome after Heart Transplant Using Anti-Thymocyte Globulin

Abstract

Giant cell myocarditis (GCM) has a grim prognosis of transplant-free survival of only 70% in 1 year. However, the prognosis of transplanted GCM patients remains unreported. We report an outcome case-series of 7 transplanted patients with excellent outcomes with an aggressive management strategy. Total 7 previously healthy patients underwent heart transplant for GCM. Most patients were >55 years age and 3/7 were females. One death was noted in a median 375 days follow up. Findings are summarized in table 1. All patients presented with cardiogenic shock, multiorgan failure, elevated troponin and recurrent ventricular tachycardia (VT) requiring temporary/durable ventricular assist device placement. Except one, all patients underwent transplant in their index hospitalization to Cedars-Sinai Hospital. Pre-transplant GCM treatment is not available on one patient (#3 in table 1) who was transferred from another facility for sensitization. Of the other 6 patients, four were diagnosed prior to transplant and received antithymocyte globulin (ATG) for 3-5 days, high dose steroid (methylprednisolone 500mg to 3gram x3 days) followed by prednisone taper and an additional immunosuppressant such as tacrolimus, cyclosporine or mycophenolate. The patients diagnosed with GCM post-transplant and patient #3 received ATG for 5 days followed by intravenous immunoglobulin (IVIG) for 2 days. All transplanted patients are currently maintained on mycophenolate, tacrolimus and prednisone. No patient had infectious complications or recurrence of GCM on endomyocardial biopsy. No patient had worse than 1R cellular rejection. Patient #5 had recurrent mild grade cellular rejection (1R) complicated with sinus arrest which was treated with ATG and steroids. The patient however passed away from refractory asystole while being admitted for syncope on the 267th day. We report an excellent survival rate in our GCM cohort without signs of recurrence, using ATG in the peri-transplant period.