Echocardiograms were performed in 11 patients with constrictive pericarditis or effusive-constrictive pericarditis confirmed by cardiac catheterization and pericardiectomy. Three echocardiographic patterns of pericardial disease were noted and were related to three types of pericardial pathology. Parallel moving echoes separated by a clear space were reflected from chronically fibrosed and thickened pericardium without associated pericardial exudate. Effusive-constrictive pericarditis or subacute wet pericarditis was characterized on the echocardiogram by a posterior echo-free space representing the liquid pericardial effusion and multiple ultrasonic lines from the thickened visceral pericardium. Subacute dry pericarditis was associated with numerous ultrasonic signals filling the space between the visceral pericardium and the relatively flat parietal pericardium. These ultrasonic signals were reflected from coagulated pericardial exudate which was adherent both to the parietal pericardium and the visceral pericardium. Parallel moving echoes or dense bands of echoes were reflected from either or both thickened visceral and parietal pericardium.