Fulminant Myocarditis in Fontan Patient Treated with Mechanical Circulatory Support and Heartmate 3

Abstract

Introduction Cardiogenic shock is a rapidly progressive condition associated with high mortality, often necessitating the use of mechanical circulatory support. Single ventricle physiology with Fontan presents many unique anatomical and hemodynamic challenges, and there is limited published experience with left ventricular assist devices (LVAD) in this population. Case Report A 30 year old female with pulmonary atresia with intact ventricular septum and lateral tunneled Fontan presented with chest pressure followed by sustained ventricular tachycardia (VT). Her echo demonstrated severely reduced left ventricular (LV) function with ejection fraction of 15-20%. Endomyocardial biopsy showed lymphocytic myocarditis, and she was treated with pulse steroids and IVIG. Given worsening shock and multiorgan failure with rapid vasopressor escalation, she was placed on femoral VA ECMO with Impella CP for venting. She eventually had LV apical cannulation and aortic graft via an upper hemisternotomy and left thoracotomy as a left ventricular assist device (KVAD). Her course was notable for persistent VT, shock liver, and renal failure requiring dialysis. After 3 weeks of mechanical support, she demonstrated recovery in end organ function and normalization of mental status, allowing for extubation and physical therapy. Given her high BMI and inability to list for a heart transplant, she underwent successful implant of a Heartmate 3 LVAD (via the original left thoracotomy using the previously placed aortic graft). Despite repeatedly negative surveillance and preoperative COVID19 tests following her initial recovery, postoperatively she developed de novo COVID19 infection complicated by respiratory failure, vasodilatory shock, renal failure, complement deposition, inflammatory storm, and concern for Fontan thrombosis. Despite aggressive treatment, she passed away from her COVID19 complications. Summary We present a case of fulminant cardiogenic shock due to lymphocytic myocarditis in a patient with Fontan physiology that was bridged with VA ECMO and KVAD and eventually received a Heartmate 3. Unfortunately, she passed away from de novo COVID19 infection. This case highlights several unique aspects such as the management of profound cardiogenic shock in complex congenital heart disease and the use of mechanical support in single ventricle Fontan physiology.