Myocardial Injury in Severe COVID-19 Compared to Non-COVID Acute Respiratory Distress Syndrome.

Background: Knowledge gaps remain in the epidemiology and clinical implications of myocardial injury in COVID-19. Our goal was to determine the prevalence and outcomes of myocardial injury in severe COVID-19 compared to acute respiratory distress syndrome (ARDS) unrelated to COVID-19. Methods: We included intubated COVID-19 patients from 5 hospitals between March 15 and June 11, 2020 with troponin levels assessed. We compared them to patients from a cohort study of myocardial injury in ARDS. We performed survival analysis with primary outcome of in-hospital death associated with myocardial injury. We performed linear regression to identify clinical factors associated with myocardial injury in COVID-19. Results: Of 243 patients intubated with COVID-19, 51% had troponin levels > upper limit of normal (ULN). Chronic kidney disease, lactate, ferritin and fibrinogen were associated with myocardial injury. Mortality was 22.7% among COVID-19 patients with troponin 10xULN (P< 0.001). The association of myocardial injury with mortality was not statistically significant after adjusting for age, sex and multi-system organ dysfunction. Compared to non-COVID ARDS patients, patients with COVID-19 were older with higher creatinine and less favorable vital signs. After adjustment, COVID-19 was associated with lower odds of myocardial injury compared to non-COVID ARDS (OR 0.55 95% CI 0.36-0.84, P=0.005). Conclusions: Myocardial injury in severe COVID-19 is a function of baseline comorbidities, advanced age and multisystem organ dysfunction similar to traditional ARDS. The adverse prognosis of myocardial injury in COVID-19 relates largely to multisystem organ involvement and critical illness.