Severe postcardiac-transplant rejection associated with recurrence of giant cell myocarditis.

Giant cell myocarditis is a disease of unknown etiology with several controversial aspects: clinical course, therapeutic management, recurring risk after heart transplantation, and histopathological factors. We report a case of giant cell myocarditis that recurred after orthotopic heart transplantation and an uneventful postoperative period. The myocardial inflammatory process in this patient showed various evolutive phases: an acute onset of diffuse giant cell myocarditis, an evolution into a granulomatous form of inflammation within the explanted heart, and a recurrence with multiple giant cell inflammatory infiltrates in the transplanted heart. Moreover, the patient presented a severe clinical course after surgery with precocious and continuous acute rejections despite the repeated immunosuppressive treatments. In this article we discuss the morphological aspects of the disease and the postoperative course of this case in relation to the possible immune dysregulation of patients affected by myocarditis before heart transplantation.