Surgical treatment for Löffler's endocarditis with left ventricular thrombus and severe mitral regurgitation: a case report.

A 65-year-old female was admitted to our hospital because of dyspnea. Laboratory examinations revealed hypereosinophilia at a local hospital. Transthoracic and transesophageal echocardiography showed normal left ventricular dimension and function. The left ventricular apex was obliterated and the posterior and lateral walls were thickened by an abnormal mass. The posterior mitral leaflet was encapsulated by this abnormal mass. The limited motion of the posterior mitral leaflet caused mitral malcoaptation, resulting in severe mitral regurgitation. Hypereosinophilia was considered to be idiopathic, as no other disorders known to cause secondary eosinophilia were found. No other organ dysfunction was associated with the condition. Thus, the diagnosis was Loffler's endocarditis associated with hypereosinophilic syndrome. The patient was given conservative medical treatment immediately on admission. However, heart failure caused by mitral regurgitation would be difficult to treat with conservative medical treatment, so we chose a surgical strategy. The symptoms obviously improved after valve replacement and removal of the abnormal mass, and the patient was discharged. However, she died of cerebral infarction at a local hospital 3 months later.