The treatment of thyrocardiac disease with radioactive iodine

Abstract

Summary We have presented our experience with 1,603 hyperthyroid patients treated from 1947 to 1954 from our material of over 3,000 patients treated to date. There were 187 with congestive failure, 30 with angina pectoris and 32 with both congestive failure and angina pectoris. In addition, there were 107 patients with atrial fibrillation but without congestive failure or angina. The females had a lower incidence of angina pectoris and pure fibrillation than could be expected on a statistical basis. Advancing age increased the incidence of all cardiac manifestations. The duration of the thyrotoxicosis before treatment had only a relatively slight effect on the appearance of cardiac symptoms. There was no difference in the total number of doses of I 131 necessary to control the cardiac and the noncardiac patients in this series. The total dose of I 131 administered was higher in the cardiac patients but part of this overdosage was deliberate. Corrected for age, nodular goiter seemed more likely to produce cardiac symptoms, particularly in the older age groups. Tachycardia, of almost similar degree, was present in both the and the non-cardiacs and responded almost equally well to I 131 therapy. Atrial fibrillation was present in 15 per cent of the entire series and in 51 per cent of the cardiacs before treatment. All but one of those with pure fibrillation reverted to sinus rhythm and 24 per cent of the continued to have atrial fibrillation. Atrial fibrillation was uncommon with angina pectoris. Hypertension, systolic and diastolic, was more frequent in the and after therapy the systolic pressure fell and diastolic pressure rose both in the and in the others. There was striking improvement in all types of thyrocardiac disease as a result of I 131 therapy. Angina and uncomplicated atrial fibrillation were relieved in almost 100 per cent of the cases. The permanent myxedema rate for the entire series was 7 per cent. For the cases of angina pectoris it was 13 per cent. Part of this increase was deliberate. The cardiac patients contributed a disproportionately large number of the total deaths. The recurrence rate was 0.75 per cent for the entire series and 1.2 per cent for the cardiac group.