GIANT CELL MYOCARDITIS: A SILENT BUT DEADLY KILLER

Abstract

SESSION TITLE: Cardiovascular Cases SESSION TYPE: Med Student/Res Case Report PRESENTED ON: 10/22/2019 3:45 PM - 4:45 PM INTRODUCTION: Giant cell myocarditis (GCM) usually affects previously healthy adults and is a rapidly progressive and frequently fatal disease, accounting for approximately 17% of all myocarditis fatalities. Early diagnosis is critical, with evidence showing rapidly instituted cyclosporine-based immunosuppression can improve transplant-free survival. CASE PRESENTATION: A 56 year old male with a history of Type 2 Diabetes presented with 1 week of exertional dyspnea and lightheadedness. Initial exam and tests were remarkable for a mild Troponin leak. EKG revealed Left bundle branch block and transthoracic echocardiogram (TTE) showed a normal ejection fraction (EF) and Left Ventricular (LV) internal Dimension-Diastole of 5.4cm. Stress test, nuclear imaging and Left Heart Catheterization were normal. An event monitor documented exercise induced bradycardia leading to the placement of a dual chamber pacemaker. Repeat ECHO done at the time showed normal EF and a mild circumferential pericardial effusion. In the following two months the patient developed worsening exertional dyspnea (NYHA III). A CT angiogram revealed a large pericardial effusion with tamponade physiology. The aspirate showed 304 cells with 94% monocytes, protein of 4.4g/dl, and cytology revealed reactive mesothelial and chronic inflammatory cells. CRP was elevated. Repeat ECHO showed LV EF of 30% with akinesis of inferior and inferolateral wall as well as diffuse hypokinesis and severely increased RV size and RV thrombus. He was begun on anticoagulation. Subsequently, right heart catherization showed elevated RA pressures and cardiac MRI showed Biventricular dilation and nondiagnostic delayed gadolinium enhancement imaging. Endomyocardial biopsy from RV was not suggestive of GCM. Patient subsequently developed progressive cardiogenic shock requiring dual Ventricular Assist Device placement. On analysing excised core of LV apex for cannula placement, it revealed granulomatous myocarditis with Giant cell formation and pericarditis. He was started on milrinone, high dose steroids and anticoagulation for suspected GCM. An RVAD was placed. Eventually patient returned with fulminant septic shock and died. DISCUSSION: This case reveals the rapidly progressive nature of GCM,which from presentation, has a median survival of 3 months to death or transplant without appropriate therapy. Biopsy is diagnostic in >70% cases if done early, however false negatives are frequent due to the patchy nature of the disease CONCLUSIONS: With immunotherapy, the 5-year survival rate free of transplant is between 52-72%. Transplant is an effective strategy however GCM can recur in around 25% of transplanted hearts. Reference #1: Giant Cell Myocarditis: A Brief Review ; Arch Pathol Lab Med. 2016 Dec;140(12):1429-1434 : Xu J, Brooks EG Reference #2: Diagnosis, Treatment, and Outcome of Giant-Cell Myocarditis in the Era of Combined Immunosuppression;Riina Kandolin, Jukka Lehtonen, Kaisa Salmenkivi: DOI:10.1161/CIRCHEARTFAILURE.112.969261 Reference #3: Idiopathic Giant-Cell Myocarditis — Natural History and Treatment; Leslie T. Cooper, Jr., Gerald J. Berry : N Engl J Med 1997; 336:1860-1866 DISCLOSURES: No relevant relationships by Tanya Chandra, source=Web Response No relevant relationships by Abhas Khurana, source=Web Response No relevant relationships by Osama Mukarram, source=Web Response No relevant relationships by Anand Muthu Krishnan, source=Web Response No relevant relationships by Rudra Ramanathan, source=Web Response No relevant relationships by Nitya Sthalekar, source=Web Response