Myocardial lesions in patients with COVID-19. Autopsy case series

Introduction. Morphological data on SARS-CoV-2-associated heart damage and its mechanisms are rather limited. However, clinical and morphological features of myocardial lesions in COVID-19 patients have been described and include myocardial ischemia, acute coronary syndrome, and acute myocarditis. The prevailing features of myocardial lesions and their consequences are still controversial. The aim of our research was to evaluate the morphological features of myocardial lesions in patients with severe COVID-19, using routine histological examination and immunohistochemistry (CD45) to confirm myocardial inflam-matory infiltration. Materials and methods. We analyzed samples of the left ventricular myocardium obtained during autopsy examination of 48 patients with severe COVID-19 who died from SARS-CoV-2-associated pneumonia. We used histological description and immunohistochemical methods. Results. The results revealed several histopathological features of COVID-19-associated myocardial lesions, including acute ischemia (25% of cases) and mild inflammatory changes termed borderline myocarditis (18.75% of cases). Other significant findings in the myocardium included microcirculatory vessel thrombosis. Conclusion. The study confirms the existing data on damage to myocardium in severe COVID-19. However, further studies are warranted. It may contribute to the development of new management strategies for severe COVID-19 patients. Keywords: SARS-CoV-2, heart, ischemia, myocarditis