Recurrent giant cell myocarditis following orthotopic heart transplant resulting in urgent redo orthotopic heart transplantation: a case report.

Background: Giant cell myocarditis (GCM) is a severe and rapidly progressing condition that can lead to end-stage heart failure. We present a case of a 51-year-old male with a history of orthotopic heart transplantation (OHTx) for GCM, who experienced recurrent GCM in the allograft, leading to progressive heart failure and the need for a second heart transplant.

Case Summary: A 51-year-old male with a history of OHTx for GCM presented with rapidly worsening heart failure symptoms. Despite initial stability, he deteriorated to cardiogenic shock and required intensive support. His clinical course was complicated by recurrent COVID-19 infections, worsened left ventricular ejection fraction, and withdrawal of guideline-directed medical therapy. Imaging showed extensive scar burden, and subsequent investigations ruled out coronary artery disease. With declining functional status and worsening cardiogenic shock, he was re-listed for OHTx and successfully underwent a second heart transplant.

Discussion: Giant cell myocarditis poses challenges due to its aggressive nature. Early, aggressive immunosuppression and mechanical circulatory support are crucial. The recurrence rate of GCM post-OHTx is notable, often within the first year, and the optimal immunosuppressive regimen remains uncertain. In this case, GCM recurrence following OHTx led to continued deterioration despite treatment, necessitating a second heart transplant. This unique case emphasizes the complexity of managing recurrent GCM post-OHTx.