Prognostic implications of myocardial injury in patients with and without COVID-19 infection treated in a university hospital

INTRODUCTION AND OBJECTIVES: Cardiac troponin, a marker of myocardial injury, is frequently observed in patients with COVID-19 infection. Our objective was to analyze myocardial injury and its prognostic implications in patients with and without COVID-19 infection treated in the same period of time. METHODS: The present study included patients treated in a university hospital with cardiac troponin I measurements and with suspected COVID-19 infection, confirmed or ruled out by polymerase chain reaction analysis. The impact was analyzed of cardiac troponin I positivity on 30-day mortality. RESULTS: In total, 433 patients were distributed among the following groups: confirmed COVID-19 (n = 186), 22% with myocardial injury (n = 41); and ruled out COVID-19 (n = 247), 21.5% with myocardial injury (n = 52). The confirmed and ruled out COVID-19 groups had a similar age, sex, and cardiovascular history. Mortality was significantly higher in the confirmed COVID-19 group than in the ruled out group (19.9% vs 5.3%, P < .001). In Cox multivariate regression analysis, cardiac troponin I was a predictor of mortality in both groups (confirmed COVID-19 group: HR, 3.54; 95%CI, 1.70-7.34; P = .001; ruled out COVID-19 group: HR, 5.57; 95%CI, 1.70-18.20; P = .004). The predictive model analyzed by ROC curves was similar in the 2 groups (P = .701), with AUCs of 0.808 in the confirmed COVID-19 group (0.750-0.865) and 0.812 in the ruled out COVID-19 group (0.760-0.864). CONCLUSIONS: Myocardial injury is detected in 1 in every 5 patients with confirmed or ruled out COVID-19 and predicts 30-day mortality to a similar extent in both circumstances.