Heart size and function after radiation therapy to the mediastinum in patients with Hodgkin's disease.

: Changes in the transverse heart diameter and cardiothoracic ratio were determined by comparing the pretreatment and last follow-up posteroanterior chest x-rays of 96 patients with stage I-III Hodgkin's disease who had received radiation therapy (RT) to the mediastinum, with the same parameters observed in 20 similar patients whose mediastinum was not irradiated. A significantly higher proportion of patients who had received RT to the mediastinum had a decrease in transverse heart diameter and cardiothoracic ratio. Among patients presenting with a large mediastinal mass, these changes were more pronounced as compared to the other groups; however, this difference was not of statistical significance. First-pass left ventricular ejection fraction (LVEF) performed with 99mTc pertechnetate (obtained in 55 of these patients 30-120 months after RT to the mediastinum) was compared with the LVEF of 20 normal controls. The control group had a significantly higher LVEF than the group of patients who had received RT to the mediastinum. No correlation was observed between changes in these parameters and the use of adjuvant, salvage, or no chemotherapy after mediastinal RT. None of these patients presented congestive heart failure or constrictive pericarditis, but our findings indicate a subclinical cardiomyopathy in more than one-half of the patients who received RT to the mediastinum, suggesting that the incidence of heart damage after mediastinal RT might be higher than expected. Prospective studies are necessary to elucidate the incidence and implications of this potentially serious complication.