Radiation therapy may affect all of the layers of the heart (epicardial arteries, pericardium, valves, and myocardium). This is especially true after mediastinal or breast irradiation. Coronary artery disease, with resultant myocardial infarction, is the most common cause of death. We present a patient who developed typical constrictive pericarditis as well as valve lesions typical of radiation toxicity (the mitral valve leaflets were thickened at their bases, with the tips spared). The pericardial constriction was manifested by all of the typical echo Doppler findings, namely septal bounce, dilated inferior vena cava, significant respiratory drop in inspiratory mitral E velocity with a normal tissue Doppler e', and expiratory reversal of flow into the hepatic veins.