The angle between theQRSandTvectors reflects the consistency or inconsistency of the processes of de- and repolarization of the ventricles of the heart and is considered one of the indicators of global electrical heterogeneity of myocardium. In recent years, the prognostic value of theQRS-Tangle has been demonstrated in relation to total and cardiovascular mortality, both in the population and in various groups of patients. The mechanisms of this phenomenon are not completely clear. The review analyses studies published over the past five years on the relationship between theQRS-Tangle and mortality, as well as coronary heart disease and heart failure. Possible mechanisms for increasing theQRS-Tangle are discussed. Data are given on the use of theQRS-Tangle in diagnostic and prognostic scales, including in combination with other indicators of global electrical heterogeneity of myocardium.

The aim of the work is to compare vectorcardiographic (VCG) variables - spatial QRS-T angle and electrocardiographic ventricular gradient (VG) with echocardiography (EchoCG) data in patients with idiopathic pulmonary hypertension (IPH) and chronic thromboembolic pulmonary hypertension (CTEPH). Materials and methods. In 40 patients with IPH and 40 patients with CTEPH at the age of 45±12 years, systolic pulmonary artery pressure (SPAP); the sizes of heart chambers, parameters of RV systolic and diastolic function were evaluated with EchoCG. The QRS-T and VG angles were calculated on the VCG, derived from 12-lead digital ECG. Results. In all patients SPAP was greater than 40 mm Hg (mean 83±18 mm Hg), EchoCG data indicated hypertrophy and dilatation of RV, its systolic and diastolic function; dilatation of the right atrium (RA). Prognostically unfavorable changes in EchoCG were observed: the presence of pericardial effusion in 35 (44%) patients, RA area greater than 26 cm2 in 18 (23%) patients; TAPSE less than 1.5 cm in 37 (46%) patients. EchoCG and VCG variables had statistically significant differences in patients with III-IV functional class in comparison with I-II functional class. Statistically significant moderate correlations between VCG and EchoCG variables were revealed. VCG variables allowed to separate patient groups with the presence and absence of prognostically unfavorable changes in EchoCG with sensitivity from 54 to 78% and specificity from 66 to 87%. Conclusion. In patients with IPH and CTEPH, changes of QRS-T angle and VG correlate with SPAP, the size of RV and RA, parameters of RV systolic and diastolic function. The possibility of the use of QRS-T angle and VG for the detection of patients with prognostically unfavorable echocardiographic changes in the general group of patients with IPH and CTEPH has been shown.

No abstract

Introduction. The prevalence of arterial hypertension (AH) among the adult population of Russia is high; up to 48% of deaths are due to its complications. Recently, prognostic indicators of the electrocardiogram (ECG) have attracted the attention of researchers. One of them is the QRS-T spatial angle (sQRS-Ta).The aim of the work is to study what clinical, laboratory and echocardiographic parameters are associated with increased sQRS-Ta in patients with AH.Material and methods. The study included 240 AH patients (48% men), mean age 62 ± 11 years. The study did not include patients with valvular disease, bundle branch block, preexcitation and ventricular pacing. Orthogonal leads were synthesized from digital ECGs in 12 leads and sQRS-Ta was calculated as a spatial angle between the integral QRS and T vectors. sQRS-Ta ≥ 90° was considered enlarged. We assessed the associations sQRS-Ta ≥ 90° with the following indicators by the method of logistic regression: sex; the presence of cardiovascular diseases; 5 age groups; overweight, obesity; smoking; heart rate (HR); systolic blood pressure (SBP), diastolic blood pressure; pulse blood pressure; blood glucose; total cholesterol; end-diastolic dimension (EDD) of the left ventricle (LV), LV wall thickness, relative LV wall thickness, left ventricular myocardial mass (LVMM), LVMM/body surface area (BSA); LVMM/height in the degree of 2,7, the presence of LV diastolic dysfunction.Results. According to univariate logistic regression, sQRS-Ta ≥ 90° associations were found with age, SBP, obesity, heart rate, LV EDD, LVMM, LVMM/BSA, and LVMM/ height2,7. In multivariate logistic regression models, the contribution of SBP ≥ 140 mmHg (odds ratio (OR) 2,22, 95% CI 1,20–4,10; p=0.01), age 55–64 years (OR 1,87; 1,01–3,44; p=0 .04), increased LV EDD (OR 2,70; 95% CI 1,27–5,72; p=0.01) and HR (OR 2,27; 95% CI 1,10–6,05; p =0.01) was independent.Conclusions. According to multivariate analysis, independent predictors of an increase in sQRS-Ta in patients with AH were SBP ≥ 140 mm Hg, an increase in LV EDD, HR > 80 beats/min, and age 55–64 years.