Constrictive pericarditis masquerading as mitral stenosis.

The five patients presented were considered to have mitral stenosis because of a history of dyspnea on exertion or paroxysmal atrial fibrillation, the presence of a loud first heart sound with an "opening snap," a loud pulmonary component of the second heart sound, electrocardiographic evidence of right axis deviation and left atrial enlargement or radiological evidence of cardiomegaly, especially left atrial and right ventricular enlargement. The correct diagnosis of constrictive pericarditis was made by cardiac catheterization and confirmed at surgery. The echocardiogram was found to be very helpful in the differential diagnosis. The demonstration of normal motion of the anterior mitral leaflet ruled out the presence of mitral stenosis.