Loeffler Endocarditis

Loeffler endocarditis is an eosinophilic-mediated restrictive cardiomyopathy occurring as part of the spectrum of hypereosinophilic syndromes. First described by W. Loeffler in 1936, Loeffler endocarditis is associated with peripheral eosinophilia and is one of the rare complications of hypereosinophilic syndromes. Extensive eosinophilic infiltration and damage to multiple organs characterize hypereosinophilic syndromes. Loeffler endocarditis results in impaired heart relaxation with impaired diastolic filling.  The predominant pathology of Loeffler endocarditis is diffuse eosinophilic infiltration of the myocardium. Cardinal manifestations of Loeffler endocarditis include left or right heart failure, thromboembolic events (stroke, limb ischemia, renal infarction), or arrhythmia. Life-threatening clinical presentations warrant immediate initiation of therapy, including steroids or immunosuppressive therapy. Eosinophilic endomyocardial disease or fibroblastic endocarditis can be used interchangeably for Loeffler endocarditis. Endomyocardial fibrosis is a disease closely resembling the late stage of Loeffler endocarditis.