Contracted form of primary endocardial fibroelastosis in a young adult without congestive heart failure.

A case of a 24-year-old man with the contracted form of primary endocardial fibroelastosis diagnosed by left ventricular endomyocardial biopsy showing a markedly thickened endocardium with fibroelastic proliferation is reported. He had no evident symptoms of congestive heart failure except for shortness of breath on moderate exertion. Echocardiogram showed thickened and dense echoes from the left side of the septum and from the posterior left ventricular endocardium. Hemodynamic and angiographic studies revealed marked elevation of right and left ventricular end-diastolic pressures with dip and plateau pressure contours, moderate pulmonary hypertension, left atrial enlargement and mild mitral regurgitation. Further elevation of right and left ventricular diastolic pressures and pulmonary artery pressure was observed at the second evaluation after 5 years. Our patient suggests that primary endocardial fibroelastosis should be included in the differential diagnosis of adult patients with obscure types of cardiac disease.