Introduction

Join Thomas Jefferson University FITs, Drs. Sean Dikdan, Rachel Debenham and Harsh Doshi, as well as Cardionerds, Dan Ambinder and Karan Desai, on this incredible story of a young man who presented with ventricular arrhythmias and cardiogenic shock. The TJU Cardionerds expertly walk us through a rare diagnosis, his course over several years and his ultimate treatment with heart transplantation. From the evaluation of cardiogenic shock to the role of endomyocardial biopsy to facing inequities in organ allocation, there are learning pearls for every listener!   CME is unavailable for this episode. Jump to: Patient summary - Case media - Case teaching - References Episode Graphic by Dr. Carine Hamo CardioNerds Case Reports PageCardioNerds Episode PageCardioNerds AcademyCardionerds Healy Honor Roll CardioNerds Journal ClubSubscribe to The Heartbeat Newsletter!Check out CardioNerds SWAG!Become a CardioNerds Patron! Patient Summary A 35 year old healthy male presents with cardiogenic shock and new heart failure with reduced ejection fraction. He has ventricular instability and is diagnosed with giant cell myocarditis by endomyocardial biopsy. His course over several years includes LVAD bridge to heart transplantation. He then has a recurrence of giant cell myocarditis in the transplanted heart which is successfully treated with high dose immunosuppression.  Case Media ABClick to Enlarge A. ECG, B. CXR Episode Schematics & Teaching CardioNerds Myocarditis, updated 1.20.21 Giant Cell Myocarditis Pearls Giant cell myocarditis (GCM is a rare – and often fatal - cause of acute myocarditis. A hallmark of GCM is the presence of multinucleated giant cells; however, these may take 1-2 weeks to appear and can also be seen in sarcoidosis.Most etiologies of fulminant myocarditis do not have bradyarrhythmias as a prominent feature, and their presence should increase the suspicion for sarcoidosis, Chagas disease, or GCM.While non-specific, a clue to the diagnosis of GCM amongst other causes of myocarditis could be rapid clinical deterioration with minimal response to guideline directed therapy, including a lack of spontaneous recovery on mechanical support which more commonly occurs in fulminant lymphocytic myocarditis.Mechanical support is typically needed in the management of GCM, either as a bridge to transplantation or recovery.GCM can recur in the transplanted heart. This happens in up to 25% of transplant patients and warrants aggressive immunosuppression which usually is sufficient to ensure disease remission. Notes - Giant Cell Myocarditis What is Giant Cell myocarditis (GCM)?Giant cell myocarditis (GCM) is an extremely rare – and often fatal – cause of acute non-infectious myocarditis. The pathophysiology of GCM is poorly understood, but thought to be a T-cell mediated autoimmune process leading to diffuse or multifocal inflammatory infiltrate, including lymphocytes with multinucleated giant cells (note multinucleated giant cells are not exclusive to GCM and can be seen in sarcoidosis as well). It has been estimated to occur at a rate of 0.13 cases per 100,000 people (one in a million).It typically affects the myocardium in isolation and may not have any extracardiac manifestations, presenting with rapid hemodynamic deterioration, ventricular arrhythmias, and at times bradyarrhythmias.  The rate of death or cardiac transplantation has been estimated at 89%, with a median survival of 5.5 months from the onset of symptoms to the time of death or transplantation.When should you be suspicious of GCM?The classic presentation is in a middle-aged Caucasian male who develops acute or subacute nonischemic cardiomyopathy (NICM) with clinical heart failure that progressively worsens. These patients often develop cardiogenic shock or arrhythmic instability – including both ventricular arrhythmia and conduction delays/heart block.