201Tl scintiscanning of the myocardium following radiotherapy of the thoracic region

40 patients were examined by 201Tl scintiscanning after radiotherapy of the thoracic region in breast cancer and metastasizing testicular tumors, resp. The results allowed to evaluate the clinical and electrocardiographic findings in 105 follow-up patients. From 40 patients with the greater part having no cardiac symptoms, 22 revealed irreversible 201Tl fixation disturbances and 10 storage deficiency under stress with repletion after rest. These findings are interpreted as myocardial fibrosis or ischemic reaction due to radiotherapy and conclusions for follow-up checks are recommended