Evolution to dilated cardiomyopathy from acute eosinophilic pancarditis in Churg-Strauss syndrome

We describe the clinical manifestations of a patient with Churg-Strauss syndrome who presented with severe acute cardiac involvement and whose disease evolved to dilated cardiomyopathy (DCM), with special reference to the histopathological findings. Endomyocardial biopsies, conducted sequentially, three times within 10 months, revealed severe eosinophilic endomyocarditis in the acute phase, interstitial fibrosis in the subacute phase, and endocardial thickening with mural thrombi, at 10 months. Although acute inflammation associated with elevation of eosinophil granule proteins subsided with steroid therapy, left ventricular dilatation with reduced contractility progressed. A subgroup of DCM is not considered to be idiopathic but, rather, an aftereffect of hypereosinophilic heart disease.