Loeffler endocarditis and restrictive cardiomyopathy with biventricular apical thrombi

Loeffler endocarditis is a serious complication of idiopathic hypereosinophilic syndrome (HES) characterized by a peculiar type of fibrosing endomyocarditis [1]. It results in various cardiac disorders and systemic embolism due to intracardiac thrombus, and these manifestations are the major causes of morbidity and mortality. Although there is still no definite therapy for Loeffler endocarditis and the prognosis is poor with high mortality rates, steroid therapy may be effective if treated at the appropriate period. Echocardiography is a mandatory evaluation in HES patients and useful to detect cardiac manifestations. A 33-year-old man with medical history of pulmonary embolism and hepatitis B was admitted to our institution with activity-induced dyspnea and systemic edema. An abnormal blood eosinophil count (1820 per lL) was also reported. Bone marrow was normocellular on examination. Echocardiography demonstrated the presence of pronounced biventricular apical thrombi, and enlarged atriums with normal LV dimension and ejection fraction (Fig. 1). Transmitral flow pattern was restrictive with increased E/A ratio (4.3) and shortened deceleration time (85 ms). Cardiac catheterization demonstrated markedly elevated biventricular end-diastolic pressure, which differed by 11 mmHg, as well as pulmonary artery pressure of 55 mmHg with a normal LV ejection fraction of 63 % (Fig. 2). These hemodynamics were consistent with restrictive cardiomyopathy. Endomyocardial biopsy remains the diagnostic gold standard, because only biopsy can detect endocardial infiltration. Thus, despite the iatrogenic complications such as embolism, endomyocardial biopsy was performed, revealing infiltration of eosinophils into the myocardium. Together, these findings confirmed a diagnosis of Loeffler endocarditis. Oral anticoagulation with Coumadin and high-dose steroid therapy was promptly initiated, resulting in improvement of clinical symptoms and reduction of E/A ratio (4.3 to 3.0).