[Changes of the Heart Rhythm in Imbalance of Thyroid Gland Hormones and its Morphology in Outbred Rats].

Aim: To analyze the relationship between the occurrence of atrial fibrillation (AF) and thyroid dysfunction caused by low concentrations of free triiodothyronine (FT3), free triiodothyronine and free thyroxine (FT3 and FT4), and high concentrations of free thyroxine (FT4) with normal values of thyroid-stimulating hormone (TSH) in experiments on outbred rats.

Material And Methods: The pathogenesis of AF with low concentrations of FT3, FT3 and FT4, and a high concentration of FT4 was studied in an experiment on 146 outbred rats. In the experiment, hypothyroidism, euthyroidism, and thyrotoxicosis were modeled by changing the concentrations of thyroid hormones, and the effect of these conditions on ECG and the incidence of AF was evaluated.

[The influence of subclinical thyroid dysfunction on cardiac hemodynamic and electrophysiological parameters in patients with coronary heart disease and paroxysmal atrial fibrillation].

The study included 58 patients with CHD and paroxysmal atrial fibrillation divided into 2 groups depending on thyroid hormone and thyrotropin levels. Group 1 was comprised of 24 patients with subclinical hypothyroidism, group 2 of 18 ones with subclinical hyperthyroidism. Control group consisted of l6 patients with CHD, paroxysmal atrial fibrillation and normal thvroid function.

[Thyroid hormones effects on hemodynamic and electrophysiological indices of heart performance and efficiency of antiarrhythmic drugs in paroxysms of cardiac fibrillation in patients with coronary heart disease].

The article provides the results of thyrotropic hormones (TH) influence on spontaneous paroxysms of cardiac fibrillation (CFP), central hemodynamics, electrophysiology (EP) of the heart and effectiveness of antiarrhythmic drugs (AAD) in patients with coronary heart disease (CHD). It is shown that in CFP patients TH should be evaluated in sinus rhythm and in arrhythmia. Fluctuations in TH contribute to CFP.

[Structural and electrophysiological characteristics of the heart function during paroxysmal atrial fibrillation].

Aim: To examine structural and electrophysiological predictors of the onset and establishment as chronic of cardiac fibrillation (CF).

Material And Methods: Echocardiography, transesophageal electrophysiological examination of the heart were performed in 420 cases of paroxysmal cardiac fibrillation (PCF). They were diagnosed as having new-onset (n = 68), rare (n = 92) and frequent (n = 260) PCF.