Physical examination revealed congestive heart failure, atrial fibrillation, a 4/6 systolic murmur, and pulsatile hepatomegaly. A chest radiograph showed pulmonary congestion and prominence of the cardiac border. The ECG showed atrial fibrillation (mean heart rate, 75 beats/min) and a right bundle branch block. Hematologic tests showed moderate eosinophilia (600 × 106 eosinophils/L) with partially degranulated eosinophils. The coproculture was negative for parasitic infections. Echocardiography showed left and right ventricular hypertrophy (interventricular septum, 16 mm; left ventricular [LV] posterior free wall, 13 mm; right ventricular free wall, 22 mm), LV dilation (LV end-diastolic diameter, 61 mm; LV end-systolic diameter, 50 mm), and LV dysfunction (LV ejection fraction, 35%). The right ventricular ejection fraction was 40%, and a tricuspid regurgitation ratio of 2+/4+ (in which 2+ is the grade of regurgitation and 4+ is the maximal degree of observed severity, rated on a 4-point scale as follows: 1+, minimal; 2+, mild; 3+, moderate; 4+, severe) was present. The pulmonary valve was characterized by the presence of large floating masses resulting in severe valvular stenosis (maximum gradient, 55 mm Hg). An additional mass was adherent to the atrial surface of the anterior mitral valve leaflet, causing a mild stenosis and moderate regurgitation. The aortic valve showed multiple vegetations, causing mild stenosis. Both atria were dilated. The presence of multiple valvular masses first suggested infectious endocarditis, but the results of serial hemocultures and serologic tests, including the assessment of antineutrophil cytoplasmic antibodies, were negative for that condition.