Coronavirus-19 (COVID-19), while primarily a respiratory virus, affects multiple organ systems, including the cardiovascular system. The relationship between COVID-19 and Myocarditis has been well established, but there are limited large-scale studies evaluating outcome of COVID-19 related Myocarditis. Using National Inpatient Sample (NIS) database, we compared patients with Myocarditis with and without COVID-19 infection. The primary outcome was in-hospital mortality. Secondary outcomes were acute kidney injury requiring hemodialysis, vasopressor use, mechanical ventilation, cardiogenic shock, mechanical circulatory support, sudden cardiac arrest, and length of hospitalization. A total of 17,970 patients were included in study; Myocarditis without COVID (n = 11,515, 64%) and Myocarditis with COVID-19 (n = 6,455, 36%). Patients with COVID-19 and Myocarditis had higher in-hospital mortality compared to those with Myocarditis alone (30.7% vs 6.4%, odds ratio 4.8, 95% CI 3.7-6.3, P< 0.001). That cohort also had significantly higher rates of vasopressor use, mechanical ventilation, sudden cardiac arrest, and acute kidney injury requiring hemodialysis. Given the poor outcome seen in COVID-19 related Myocarditis cohort, further work is needed for development of directed therapies for COVID-19-related Myocarditis.
