Myocardial hypertrophy (MH) due to cardiac pathology is characterized by an increase in QT interval duration and dispersion, while the findings for exercise-induced myocardial hypertrophy are contradictory. The majority of published research findings have not explored this relationship, but there have only been a few conducted studies using 24-hour ECG monitoring. The aim of the study was to determine the QT interval duration and dispersion in short-term and 24-hour ECG in endurance athletes with myocardial hypertrophy and without it. Methods: A total of 26 well-trained rowers underwent a resting 12-lead ECG, 24-hour ECG monitoring and echocardiography. Results: Athletes with MH (n = 7) at rest did not show any increase in QTc interval duration and dispersion, or mean and maximal QTc duration in Holter monitoring compared to athletes without MH (n = 19). Left ventricular mass was not significantly correlated with any QTc characteristics. Furthermore, athletes with MH had significantly longer mean QT (P = 0.01) and maximal QT (P = 0.018) intervals in Holter monitoring and higher 24-hour heart rate variability indexes due to stronger vagal effects. Conclusions: The present study demonstrated that athlete's heart syndrome with myocardial hypertrophy as a benign phenomenon does not lead to an increase in QT interval duration, or increases in maximal and mean duration in a 24-hour ECG. An increase in QT interval duration in athletes may have an autonomic nature.

Реферат. Проведено исследование влияния новокаиновых блокад внутригрудных артерий на вегетативный статус 42 больных ИБС по результатам вариабельности ритма сердца. Ключевые слова: ИБС, вегетативный статус, новокаиновая блокада. CHANGES OF THE VEGETATION STATUS IN PATIENTS WITH ISCHEMIC HEART DISEASE AFTER COMPLEXIAL TREATMENT USING NOVOCAIN BLOCKADE OF ARTERY THORAX INTER I.V. Bilalov, R.R. Bilalova Kazan State Medical University, Department of Surgical Diseases № 2Abstract. Investigation about infl uence of Novocain blockade artery thorax inter on the vegetation status of the 42 patients with ischemic heart disease by the results of heart rate variability has been made.