COVID‐19‐associated myocardial injury: A case report

Coronavirus disease 2019 (COVID‐19) is often accompanied by pneumonia and can be fatal. We report a case of COVID‐19‐associated myocardial injury mimicking fulminant myocarditis. Endomyocardial biopsy revealed numerous von Willebrand factor‐rich microthrombi with small myocardial necrotic areas, complement deposits in small vessels/microthrombi, and macrophage‐predominant interstitial infiltration. These findings, distinct from those of typical lymphocytic myocarditis, show diffuse endothelial injury, complement activation, and activated macrophages as characteristic features of COVID‐19‐associated pathogenesis. Dysregulated serum cytokine profiles predicting severe/critical COVID‐19‐associated myocardial injury were also determined. This case emphasizes the occurrence of fatal cardiac manifestation with microthrombotic injury in the early stage of COVID‐19.