A Rare Case Of Eosinophilic Myocarditis Due To Subacute Sars-cov-2 Illness

BACKGROUND: Eosinophilic myocarditis is a rare inflammatory cardiomyopathy with a poor prognosis. SARS-CoV-2 (COVID-19) illness has been associated with myocarditis, particularly of lymphocytic etiology. Although there have been cases of eosinophilic myocarditis associated with COVID-19 vaccination, there have been few reported cases secondary to COVID-19 illness, with the majority being diagnosed via post-mortem autopsy. CASE: A 44-year-old woman with no significant medical history other than recent COVID-19 illness 6 weeks prior presented with progressive dyspnea. Patient developed acute dyspnea and diffuse pruritic rash after taking hydroxyzine. Labs were significant for mild eosinophilia. Echocardiography showed biventricular systolic dysfunction with left ventricular ejection fraction of 40%, and a moderate pericardial effusion that was drained percutaneously. She underwent left heart and right heart catheterization showing elevated biventricular filling pressures, Fick cardiac index of 1.6 L/min/m(2), and no coronary disease. She was started on intravenous diuretics and transferred to our facility for further management. Her course was complicated by cardiogenic shock requiring intra-aortic balloon pump (IABP) support. Mixed venous saturations continued to decline and the patient was placed on veno-arterial extracorporeal membrane oxygenation (VA-ECMO) support. The patient underwent endomyocardial biopsy (EMB) showing marked interstitial infiltration of eosinophils and macrophages with myocyte injury (see image). She was intubated with mechanical ventilation as well due to worsening pulmonary edema and hypoxemia. She was started on intravenous steroids with improvement of hemodynamics and myocardial function and eventually VA- ECMO was decannulated to low-dose inotropic support which in turn was ultimately weaned after 3 days of mechanical support. CONCLUSION: Eosinophilic myocarditis is a rare and under-recognized sequela of acute COVID-19 infection associated with high mortality rates. It requires prompt diagnosis and aggressive supportive care, including temporary mechanical circulatory support. There are few literature-reported cases of COVID-19 myocarditis requiring use of both IABP and VA-ECMO, none of which were used in biopsy-proven eosinophilic myocarditis, with most of these cases resulting in either fatal or unreported outcomes. Most cases of covid myocarditis required IV glucocorticoids therapy in conjunction with IVIG or interferon therapy. Here, we present a rare case of cardiogenic shock secondary to biopsy-proven eosinophilic myocarditis associated with recent COVID-19 illness with a survival outcome after temporary use of IABP and VA-ECMO support, as well as aggressive immunosuppressive therapy.