Loeffler Endocarditis Complicated by Cardiogenic Shock and Angioinvasive Fusarium fujikuroi Infection: A Case Report

Background Loeffler endocarditis is a form of restrictive cardiomyopathy that affects up to half of patients with hypereosinophilic syndromes. Patients undergoing treatment of Loeffler endocarditis with immunosuppression are at increased risk of mixed cardiogenic and septic shock due to its restrictive ventricular physiology and treatment with immunosuppressive therapy. Case Summary A 64-year-old female with peripheral eosinophilia and heart failure with mildly reduced ejection fraction reported six months of fatigue, worsening lower extremity edema, palpitations, dyspnea on exertion, and orthopnea. She was diagnosed with Loeffler endocarditis based on cardiac magnetic resonance imaging and was initiated on high-dose prednisone and rituximab. While undergoing treatment of a subsequent angioinvasive fungal infection, she developed mixed cardiogenic and septic shock requiring inotropic support and broad-spectrum antimicrobials. She was eventually weaned off inotropic support and was continued on long-term posaconazole for the angioinvasive fungal infection. Discussion Patients undergoing treatment of Loeffler endocarditis with immunosuppression are at an increased risk of mixed cardiogenic and septic shock. Late-stage Loeffler endocarditis predisposes to cardiogenic shock due to restrictive ventricular physiology and thrombi obliterating the ventricular cavities, while immunosuppressive therapy increases risk of opportunistic infections. If immunosuppression is initiated before ventricular fibrosis occurs, progression of Loeffler endocarditis can be halted or reversed.