Rapid Disappearance of Intraventricular Mobile Structures with Steroids in Eosinophilic Granulomatosis with Polyangiitis

Abstract Endomyocarditis in Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare complication, commonly involving an apical mass compatible with a thrombus. However, no previous report has discussed mobile structures detected by echocardiography in a patient with EGPA. A 53-year-old man with asthma presented with low-grade fever, consciousness disturbance, and vomiting. Magnetic resonance imaging showed multiple acute infarctions in the bilateral cerebrum and cerebellum. Remarkable eosinophilia was observed, and transthoracic echocardiography showed multiple mobile structures originating from the left ventricular septum. The day after admission, he developed left partial hemianopia and intracranial hemorrhage was identified in his right occipital lobe. Skin biopsy showed infiltration of eosinophils in the arterial wall, and we diagnosed EGPA. Myocardial biopsy was performed from the right ventricular wall, and eosinophilic infiltration into the endocardium and myocardium was observed. Endomyocarditis secondary to EGPA was confirmed, and steroid therapy was immediately initiated. Ten days after steroid therapy, the mobile structures in the left ventricle disappeared completely. He suffered no recurrence of stroke with continued steroid therapy. Mobile structures in the left ventricle in patients with active EGPA could be treated conservatively with steroid therapy.