Heart Rhythm Changes in Patients With Thyroid Dysfunction

Thyroid hormones are considered the main metabolic regulators of the cardiovascular system. Their imbalance may lead to cardiac rhythm disturbances in children. Objective. To clinically and instrumentally assess changes in cardiac rhythm in children with thyroid dysfunction. Methods. A total of 65 patients aged 7–17 years with thyroid dysfunction (hypothyroidism – 34, hyperthyroidism – 31) and 30 healthy children were examined. All participants underwent ECG, echocardiography, and thyroid hormone analysis. Results. In the hypothyroidism group, sinus bradycardia (41.2%), prolonged PQ interval (23.5%), and ventricular extrasystole (11.7%) were more common. In children with hyperthyroidism, sinus tachycardia (54.8%), supraventricular extrasystole (22.5%), and shortened PQ interval (19.3%) were observed (p0.05). Echocardiography revealed diastolic relaxation disorders and myocardial hyperkinesia. Conclusion. Various types of cardiac rhythm disturbances were observed in children with thyroid dysfunction. In hypothyroidism, bradycardia and conduction disorders were predominant, while in hyperthyroidism, tachycardia and extrasystole were more pronounced. Cardiac monitoring is necessary in cases of endocrine imbalance.