Utility of cardiac magnetic resonance imaging in diagnosing eosinophilic myocarditis in a patient recently recovered from COVID-19: a grand round case report

Abstract

Background Eosinophilic myocarditis secondary to eosinophilic granulomatosis with polyangiitis is a rare disease, for which cardiac magnetic resonance imaging is a useful non-invasive modality for diagnosis. We present a case of eosinophilic myocarditis in a patient who recently recovered from COVID-19 and discuss the role of cardiac magnetic resonance imaging and endomyocardial biopsy to differentiate between COVID-19 associated myocarditis and eosinophilic myocarditis. Case summary A 20-year-old Hispanic male with history of sinusitis and asthma, and recently recovered from COVID-19, presented to the emergency room with pleuritic chest pain, dyspnea on exertion, and cough. His presentation labs were pertinent for leukocytosis, eosinophilia, elevated troponin, and elevated ESR and CRP. EKG showed sinus tachycardia. Echocardiogram showed an ejection fraction of 40%. The patient was admitted, and on day two of admission, he underwent cardiac magnetic resonance imaging which showed findings of eosinophilic myocarditis and mural thrombi. On hospital day three patient underwent right heart catheterization and endomyocardial biopsy which confirmed eosinophilic myocarditis. Patient was treated with steroids and mepolizumab. He discharged on hospital day 7 and continued outpatient heart failure treatment. Discussion This is a unique case of eosinophilic myocarditis and heart failure with reduced ejection fraction as a presentation of eosinophilic granulomatosis with polyangiitis, in a patient recently recovered from COVID-19. In this case, cardiac magnetic resonance imaging and endomyocardial biopsy were critical to identify the cause of myocarditis and helped in optimal management of this patient.