Abstract 4338261: Astrovirus-Myopericarditis Leading to Sudden Cardiac Arrest; An Unusual Complication of Common Gastroenteritis

Case Description: A 27-year-old male with unremarkable past medical history presented with non-bloody diarrhea and nausea and vomiting of 5 days duration. While in the emergency department, he reported substernal non-pleuritic and non-radiating chest pain. On cardiac monitor he was noted to have frequent premature ventricular complexes (>5%) arising with superior portion of left ventricle and ECG showed new ST elevation in lead II and aVF. Emergent coronary angiogram showed no coronary artery stenosis or vasospasm. Post cardiac catheterization he had Torsade de Pointes requiring defibrillation. Electrolytes were in normal range, but elevated cardiac biomarkers were elevated. Right heart catheterization showed elevated filling pressures with normal cardiac output and index, 5.6 L/min, and 2.3 L/in/m2, respectively. Endomyocardial biopsy was negative for lymphocytic, giant cell, or granulomatous inflammation. A Prussian blue iron stain for hemochromatosis and Congo red for amyloidosis were negative. Echocardiogram showed no structural heart disease with normal right and left ventricular size but mildly decreased function (LVEF 40-45%). Cardiac MRI showed large areas of left ventricular linear subepicardial gadolinium enhancement not in a coronary territory associated with pericarditis. He had leukocytosis and an infectious work up including gastrointestinal panel was positive for Astrovirus. He was treated with beta blockers, angiotensin receptor blocker and high dose steroids. No recurrent ventricular arrythmia noted in one week and premature ventricular complex burden decreased. He was scheduled for subcutaneous defibrillator and follow up with cardiac MRI. Discussion: Astrovirus causes gastroenteritis in about 2-5% of children and rarely adults. Murine models of Astrovirus infection showed its cardiovascular tropism. Here we present the first case of astrovirus-myopericarditis. Ventricular arrhythmias may occur due to electrolyte abnormalities that are commonly seen in a gastroenteritis as well as direct cardiac injury and inflammation caused by viral replication or bystander immune response. The localization of premature ventricular complexes shows possible origin from superior portion of left ventricle with active inflammation noted in T2 weighted cardiac MRI. Electrical instability requiring defibrillation placed our case in stage D myopericarditis.