A 65-year-old man presented to a medical center with dyspnea, peripheral edema, and orthopnea. Diagnosis of chronic systolic and diastolic biventricular heart failure secondary to Löffler endocarditis and endomyocardial fibrosis was made. A transthoracic echocardiograph showed a reduced left ventricular ejection fraction and severe right ventricular systolic dysfunction. The right ventricular cavity was nearly obliterated by a homogeneous mass, and spectral Doppler ultrasonography demonstrated diminished antegrade systolic flow across the pulmonic valve. Anticoagulation therapy with heparin was initiated. Cardiac magnetic resonance image revealed diffuse hyperenhancement of the right ventricular free wall on delayed gadolinium enhancement (image A, arrow). Catheterization of the right side of the heart with contrast ventriculogram revealed a nearly obliterated (image B, dotted line) right ventricle with interatrial passage of contrast and subsequent left ventricular opacification (image B, arrows). A 35-cm ultrasound-accelerated thrombolysis catheter was placed in the left pulmonary artery. Hemodynamic measurements demonstrated atrialization of the right ventricular pressure waveform. Hemodynamics failed to improve after 18 hours of thrombolysis, and the patient died of complications of biventricular heart failure 10 days after presentation. 

Löffler endocarditis and endomyocardial fibrosis, when encountered together, is rare and characterized by peripheral eosinophilia and the development of endomyocarditis, intracardiac thrombosis, and eventual cardiac fibrosis.¹ Patients with peripheral eosinophilia have been successfully treated with systemic steroids or eradication of the underlying parasitic infection.^2,3 Thrombectomy to manage intracardiac thrombosis secondary to Löffler endocarditis has been reported with variable results.^4,5