[Clinical considerations in the treatment of atrial fibrillation (in thyrotoxicosis patients)].

Altogether 136 patients with thyrotoxicosis complicated by atrial fibrillation were treated. After drug treatment alone and strumectomy if indicated, over two-thirds of the patients showed sinus rhythm recovery after the attainment of euthyrosis even before institution of the treatment with antiarrhythmic drugs. It is concluded that in patients with removed thyrotoxicosis, uneliminated atrial fibrillation does not interfere with surgery which should not be postponed, since 10% of the patients demonstrate unaided sinus rhythm recovery in the immediate postoperative period. The disappearance of fibrillation consequent on the treatment of thyrotoxicosis patients including those over 50 years suggests that reversible alterations in the myocardium and in its thyrotoxicosis-induced dystrophy underlie heart rhythm disorders seen in thyrotoxicosis.