Five years or more after receiving cardiac radiation, 41 patients with Hodgkin's disease and seminoma in remission were subjected to echocardiography. The abnormalities detected included pericardial thickening in 70%, thickening of the aortic and/or mitral valves in 28%, right ventricular dilatation or hypokinesis in 39%, and left ventricular dysfunction in 39%. In the 23 patients treated by an upper mantle technique with shielding, the incidence of right ventricular abnormalities and valvular thickening was significantly lower than in patients treated with modified techniques. Although no symptoms were attributable to the observed abnormalities, longer follow-up time may reveal important functional implications.