Giant Cell Myocarditis: Long Term Survival Following Left Ventricular Assist Device Implantation

Giant cell myocarditis (GCM) is a rapidly progressing and frequently fatal disease. Long term survival has been associated previously only with mechanical support and immunosuppression as a bridge to transplant. Here we present two patients with GCM who received advanced heart failure (HF) therapies with mechanical support and who survived with left ventricular assist device (LVAD) implantation. 67 y/o man with a history of coronary disease and remote revascularization progressed to stage D HF requiring inotropic therapy followed by an LVAD. At the time of implant, the consensus was that the cardiomyopathy (CM) had been a progression of ischemia. Pathological analysis of the apical core revealed GCM. He continues to be successfully supported by LVAD. 51 y/o man with history of familial CM presented in cardiogenic shock and refractory ventricular tachycardia. He was treated with veno-arterial extracorporeal membrane oxygenation as a bridge to a durable LVAD and then transplantation. Pathology from the core biopsy obtained at the time of LVAD implantation showed no evidence of GCM. He was transplanted after 2 years of mechanical support. His explanted heart showed prominent GCM with prominent fibrosis (Figure). Discussion Mechanical circulatory support (MCS) without immunosuppression, as either destination therapy or a bridge to transplantation, may be a viable option in select cases of GCM. The fact that the diagnosis of GCM is confirmed with pathology and can easily be missed generates an interesting conundrum. Recognition of the disease may change management, as it traditionally includes immunosuppression whose role in patients with durable MCS is not known and is arguably undesirable as the risk of infectious complications may be prohibitive, and its results are dubious at best. Cases like these not only show that MCS may be a viable alternative, but also suggest that such an entity as stable GCM that has not been previously recognized as a survivable entity should be considered. A limitation of MCS therapy would be the lack of right ventricular support. It is evident that further research is needed in order to accurately define, stratify, and ultimately treat this so poorly understood entity.