COVID-19 and Myocarditis: Findings from Cardiac Magnetic Resonance Imaging and Endomyocardial Biopsies

Diagnosing myocarditis is still challenging due to its varying presentation ranging from none or mild symptoms to sudden cardiac death. Clinical presentation, electrocardiography, and cardiac biomarkers seem not to be sufficient for a reliable diagnosis. In fact, an unequivocal myocardial characterization is needed, applying endomyocardial biopsy (EMB) and cardiac magnetic resonance (CMR), a technique which demonstrates high accuracy to histology. Besides the assessment of functional parameters (volumes, ejection fraction), established late gadolinium enhancement and recent T1 and T2 mapping techniques including the calculation of extracellular volume fraction allow distinct myocardial tissue analysis by a noninvasive approach without the need of radiation. However, EMB is the only method which allows the identification of the underlying etiology of cardiac inflammation. Since myocardial damage and inflammation seem to be prevalent in a considerable number of patients even in the mid-term range after COVID-19, CMR and EMB seem to be adequate tools to further investigate these findings. In this article, we will (1) review current knowledge about the role of CMR in the COVID-19 pandemic and (2) report about our own EMB findings in COVID-19 patients in the Cardiopathology Center of our University Hospital.