title: Incidence of heart disease and functional significance of changes in the electrocardiogram 10 years after radiotherapy for breast cancer.
abstract: Late cardiac complications after radiotherapy for breast cancer was studied in 197 patients examined before, 6 months after, and 10 years after treatment. The 10-year follow-up was done by survey of the files of patients who had died and re-examination of patients who were alive and free of cancer. Among 95 patients who died, 3 died of cardiopulmonary diseases. Autopsy in 32 patients showed serious cardiac abnormalities in 3. Of 102 patients alive at follow-up, 3 reported heart symptoms. Sixty-nine patients participated in the re-examination. Electrocardiogram (ECG) abnormalities were found in 19% of these patients before treatment; in 45% at 6 months, essentially due to T-wave changes in patients who had received left-sided irradiation; and in 45% at 10 years, with fewer T-wave abnormalities but more ST depression and ectopic beats. Average working capacity was 83 W before, 81 W at 6 months, and 84 W at ten years. Average heart volume was 680 ml before, 689 ml at 6 months, and 718 ml (P less than 0.01) 10 years after treatment. In conclusion, there was a high incidence of ECG T-wave changes, but they were reversible, and the perimyocardial damage indicated was functionally insignificant. The incidence of serious cardiac complications was low.
mesh_terms: D001344:Autopsy; D001943:Breast Neoplasms / Q000401:mortality / Q000532:radiotherapy* / Q000601:surgery; D002306:Cardiac Volume; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006331:Heart Diseases / Q000209:etiology* / Q000503:physiopathology; D006801:Humans; D009362:Neoplasm Metastasis; D005082:Physical Exertion; D011878:Radiotherapy / Q000009:adverse effects*; D011879:Radiotherapy Dosage; D013147:Spirometry; D014938:Work Capacity Evaluation