COVID-19-Associated Myocarditis Managed With High-Dose Steroids: A Case of Rapid Clinical and Biochemical Recovery

Myocarditis is an uncommon but serious complication of SARS-CoV-2 infection. Its diagnosis remains challenging due to clinical features overlapping with acute coronary syndromes and the lack of standardized criteria; yet, early recognition is crucial to prevent fulminant progression. We report a case of a 74-year-old woman with a recent COVID-19 infection presenting with chest discomfort, new-onset atrial fibrillation, and rising troponin levels. Despite initial treatment for non-ST elevation myocardial infarction, she experienced worsening respiratory symptoms and chest pain. Workup, including echocardiography and left heart catheterization, excluded obstructive coronary disease and revealed inferior wall hypokinesis with preserved ejection fraction. Elevated inflammatory markers (C-reactive protein (CRP), interleukin-6 (IL-6)) and clinical deterioration supported the diagnosis of COVID-19-associated myocarditis. Initiation of high-dose intravenous methylprednisolone (500 mg daily for 3 days) resulted in rapid clinical and biochemical improvement. She was discharged on a tapering dose of steroids. Six weeks of follow-up showed resolution of myocarditis with normal troponin. While evidence for steroid use in viral myocarditis is mixed, emerging case reports and reviews support immunosuppressive therapy in COVID-19-associated myocarditis. This case highlights the therapeutic benefit of high-dose corticosteroids, likely by mitigating cytokine-mediated myocardial injury. COVID-19-associated myocarditis should be considered in patients with unexplained cardiac injury and recent SARS-CoV-2 infection. Our case demonstrates that the timely administration of high-dose corticosteroids may lead to favorable outcomes. Further research is warranted to establish standardized treatment protocols and validate the efficacy of immunosuppressive therapy in this population.