Detection of radiation cardiomyopathy by gated radionuclide angiography.

Twenty-one asymptomatic adults underwent rest and exercise gated radionuclide angiography seven to 20 years after having received mediastinal radiation (2,000 to 7,600 rads) for Hodgkin's disease. None of these patients received cytotoxic chemotherapy. Twelve patients (57 percent) had abnormal left (less than 53 percent at rest and/or greater than 5 percent decrease at peak exercise) and/or right (less than 27 percent at rest and/or greater than 5 percent decrease at peak exercise) ventricular ejection fractions. Previous reports have described myocardial fibrosis occurring late after therapeutic mediastinal radiation; however, the incidence of this occurrence based on clinical follow-up has been low. Rest and exercise radionuclide angiography is a sensitive method for assessing systolic ventricular function and reveals a high prevalence of cardiomyopathy that can be linked to previous radiotherapy.