Cardiac compromise in patients recovered from COVID-19 without troponin elevation assessed by cardiac magnetic resonance imaging

Background: The disease caused by coronavirus (COVID-19) affects the cardiovascular system, whether by direct viral aggression or indirectly through systemic inflammation and multiple organ compromise. A widely used method to determine cardiac injury is troponin measurement. The aim of this study is to evaluate the prevalence of cardiac involvement (CINV) in a population recovered from COVID-19, referred to cardiac MRI (CMR), who did not present troponin elevation. Methods: There were 156 patients that recovered from COVID-19 and who did not present troponin elevation referred to CMR. CINV was considered to be the presence of: late gadolinium enhancement (LGE), edema, myocarditis, pericarditis, left ventricular systolic dysfunction (LVSD) and/or depressed right ventricular systolic dysfunction (RVSD). Results: Prevalence of CINV was 28.8%, being more frequent in men (p=0.002), in patients who required hospitalization (p=0.04) and in those who experienced non-mild cases of infection (p=0.007). RVSD (17.9%) and LVSD (13.4%) were the most frequent findings. The rate of myocarditis was 0.6%. LGE manifested in 7.1% of patients and its presence was related to less left ventricular ejection fraction (LVEF) (p=0.0001) and right ventricular ejection fraction (RVEF) (p=0.04). Conclusion: In patients who recovered from CO -VID-19, 28.8% of CINV was found. It was more frequent in men, in patients who required admission and in patients with cases of non-mild infection. The patients that presented LGE had less LVEF and RVSF.