Cardiac effects of severe hyperthyroidism and their changes in the long-term period after surgical treatment

Abstract

Background. The result of surgical treatment of goiter with severe thyrotoxicosis may be an improvement in general condition and physical activity, a decrease and/or elimination of clinical manifestations of thyrotoxic cardiomyopathy (effective treatment), or a worsening of the general condition (ineffective treatment). From the standpoint of such approach, the long­term results of surgical treatment of toxic goiter with severe thyrotoxicosis have not been sufficiently studied. The purpose was to investigate the long­term effects of surgical treatment of patients with toxic goiter and severe thyrotoxicosis with a priority study of changes in cardiac activity and physical activity. Materials and methods. Studies have been carried out in 123 surgically treated patients with severe toxic goiter. Patients’ age ranged from 21 to 74 years. The duration of thyrotoxicosis was from 18 to 74 months. Indications for surgical treatment were frequent relapses of thyrotoxicosis, progression of thyrotoxic cardiomyopathy against the background of thyrostatic therapy with the development of heart rhythm disorders and heart failure. Structural and functional changes in the heart according to B­mode echocardiography, cardiac disorders according to the results of daily Holter monitoring, physical activity according to a six­minute walk test have been studied. Long­term effects of treatment have been evaluated by gradation developed by us: good, satisfactory, unsatisfactory result and ineffective treatment. Results. It has been found that the surgical treatment of patients with toxic goiter and severe thyrotoxicosis allows eliminating thyrotoxicosis and in some patients — heart rhythm disorders, reducing the severity of clinical manifestations of thyrotoxic cardiomyopathy, improving physical activity and general condition. Studies have shown that the results of surgical treatment depended on the severity of heart rhythm disorders and heart failure, i.e. the effects of thyrotoxicosis, which develop against the background of thyrotoxic cardiomyopathy. Good and satisfactory results of surgical treatment have been obtained in 55 (44.7 %) cases, unsatisfactory results — in 40 (32.5 %) patients, and the treatment was ineffective in 28 (22.8 %) persons. Conclusions. Surgical treatment of patients with toxic goiter and severe thyrotoxicosis helps achieve positive results: to eliminate thyrotoxicosis, reduce the severity of clinical manifestations of thyrotoxic cardiomyopathy, improve cardiac activity, physical activity and general condition of patients. The long­term results of surgical treatment of patients with severe thyrotoxicosis depend on the duration of the disease, drug therapy of thyrotoxicosis and the age of the patients. With an increase in these values, treatment results deteriorate. Among existing indications for the surgical treatment of patients with toxic goiter and manifestations of severe thyrotoxicosis, the first and most important one is the presence of thyrotoxic cardiomyopathy with heart rhythm disorders. The universal indicator for predicting long­term results of surgical treatment of patients with toxic goiter is the distance covered during a six­minute walk test.

Keywords

• toxic goiter
• severe thyrotoxicosis
• surgical treatment
• long-term results