Dynamic examination of athletes is of great interest for sports medicine specialists, as it allows measuring changes in athletes’ functional state in parallel with increasing athletic performance in a one-year training cycle. The aim of the work is to assess dynamic changes in parameters of heart rate variability, central hemodynamics and physical performance in short-distance swimmers during preparatory and competitive periods of the training process. Materials and methods. The swimmers (n = 94) qualified from the second-class sport qualification to Master of Sports of International Class were examined during the preparatory and competitive periods of the training process. Short ECG recordings of 5 minutes were used for the heart rate variability (HRV) analysis according to the International Standard. Results. In the preparatory period, the autonomic equilibrium index had a mean value of 3.104 ± 0.494 1/s2, and in the competitive period – 2.459 ± 0.248 1/s2 (P = 0.295). The initial distribution of athletes depending on the value of autonomic tone, according to the classification proposed by R. M. Bayevskiy, had the following ratio in the preparatory period: 75.0 % / 20.0 % / 5.0 %, vagotonic, normotonic and sympathotonic individuals, respectively, statistically significantly indicating the prevalence of athletes with vagotonia over normotonic individuals (P = 0.0005). In the competitive period, this ratio was 60.0 % / 40.0 % / 0 %. The central hemodynamic indices showed a downward trend as evidenced by a decrease in the cardiac index from 2.954 ± 0.126·l·min-1·m-2 to 2.862 ± 0.088 l‧min-1‧m-2 (Р = 0.510), although these values matched to the eukinetic circulatory type (CT) during both training periods. However, the ratio of hypokinetic, eukinetic and hyperkinetic CT in the preparatory period was 45.0 % / 45.0 % / 10 0 %, and in competitive period – 45.0 % / 55.0 % / 0 %, respectively. The mean value of physical working capacity (PWC170/kg) in the preparatory period was 15.54 ± 0.66 kgm·min-1·kg-1, and in the competitive period it was 18.09 ± 0.53 kgm·min-1·kg-1, making an increase of 16.41 % (Р = 0.0001). The functional state index (FSI) increased significantly by 25.08 % from 5.558 ± 0.322 r. u. to 6.952 ± 0.272 r. u. (Р = 0.00001). The correlation analysis during the preparatory period showed a significant positive correlation between Mo and PWC170/kg (r = 0.46, P = 0.040), ARI and CI (r = 0.50, P = 0.026), IARP and CI (r = 0.53, P = 0.017), stress-index and SI (r = 0.52, P = 0.019) and negative – between Mo and CI (r = -0.56, P = 0.009). In the competitive period, the general tendency of correlation interaction was remained, as evidenced by revealed positive relationships between Mo and FSI (r = 0.53, P = 0.017), ARI and SI (r = 0.51, P = 0.020). Conclusions. Short-distance swimmers in the competitive period had significantly higher level of physical working capacity (by 16.4 %), the functional state index (by 25.1 %), as well as parasympathetic tone of ANS in comparison with the preparatory period. The above-mentioned hemodynamic changes and autonomic balance indicators were associated with the increase in athletic performance: 4 (20 %) swimmers qualified for the title of Master of Sports of Ukraine, 2 (10 %) swimmers – for Candidate Master of Sports, and 2 (10 %) swimmers – for first-class sport qualification.

The aim of this study was to compare the indices of heart rate variability, central hemodynamics and physical working capacity in female swimmers with different sports qualifications. Materials and methods. The indices of heart rate variability (HRV), central hemodynamics (CH) and physical development (PD) were studied in 44 female swimmers (mean age 15.00 ± 0.36 years, swimming experience – 7.40 ± 0.35 years) depending on their sports qualifications (MSIC, MS, CMS, first- and second-class athletes). To analyze the autonomic regulation of cardiac activity, power spectral and time-domain indices of HRV were used. CH were examined by the method of automated tetrapolar rheography according to W. Kubiček et al. (1970) in Y. T. Pushkar’s et al. modification (1970). Physical working capacity was measured according to the generally accepted technique on a cycling ergometer using the PWC170 submaximal test. The functional state index (FSI) was calculated using the formula patented by authors. Results. Significant differences were found between the indices of HRV, CH and PD in female swimmers with different qualifications. Thus, in the athletes with the MSIC–MS sports qualifications, heart rate was 61.0 ± 3.8 bpm, cardiac index (CI) – 2.978 ± 0.098 L·min-1·m-2 (there was a trend towards the eukinetic type of hemodynamics (TH)), stress index (SI) – 51.16 ± 12.66 relative units (r.u.), PWC170/kg – 16.98 ± 1.22 kgm·min-1·kg-1, FSI – 6.511 ± 0.422 r.u. A decrease in heart rate among them was correlated with a decrease in SI, and an increase in Mo – with a decrease in CI. In female CMS swimmers, heart rate was 61.37 ± 2.83 beats/min-1, CI – 3.021 ± 0.112 l -1min -1·m -2 , a trend towards the predominantly eukinetic TH, SI – 53.73 ± 9.41 r.u., PWC170 /kg– 14.66 ± 0.683 kgm·min-1·kg -1, FSI – 5.683 ± 0.324 r.u. Reduced values of SI and CI were associated with increased values of Mo and PWC170/kg. In first- and second-class female swimmers, heart rate was 63.05 ± 2.22 beats/min, SI – 50.62 ± 6.4 r.u. This group tended to be eytonic and eukinetic. The mean value of the PWC170/kg was 14.19 ± 0.589 kgm·min-1·kg-1 and FSI – 5.953 ± 0.337 r.u. Correlation analysis confirmed the relationship between the decrease in heart rate and CI and the increase in Mo and PWC170/kg. Conclusions. Long-term training in female swimmers at the distance of 50 to 200 meters is accompanied by the significant increase in the PWC170/kg values with qualification improving, 14.19 ± 0.589 kgm·min-1·kg-1, 14.66 ± 0.683 kgm·min-1·kg-1; 16.98 ± 1.22 kgm·min-1·kg-1, respectively, improvements in HRV (decrease in stress index and increase in Mo) and decrease in CI.

Objective: To detect residual platelet aggregation following the switch from generic (GC) to brand clopidogrel (BC) in male patients after ST-elevated myocardial infarction (STEMI). Methods: The study was designed as an open-label, prospective cohort trial. Thirty-three male STEMI patients were enrolled. All patients received dual antiplatelet therapy with aspirin (100 mg/daily) and one of six GC at a daily dose of 75 mg. After 2 weeks, all patients were switched to BC. Adrenaline- and adenosine diphosphate (ADP)-induced platelet aggregation was assessed twice: on day 14 (before the switch) and on day 21 (after 1 week of BC therapy). Results: Adrenaline-induced platelet aggregation did not differ among clopidogrel formulations. In contrast, residual 5 µM ADP-induced platelet aggregation after BC differs from GC by 14% (28.0 ± 2.5 vs. 23.9 ± 2.1%; p = 0.03). When 20 µM ADP was used as agonist, the difference was smaller (36.2 ± 2.9 vs. 34.6 ± 2.8%) but still significant (p = 0.04) favoring BC. Conclusions: After 2 weeks of therapy, switching from GC to BC was associated with a mild but significant reduction in ADP-induced platelet aggregation in male post-STEMI patients. The observed differences between GC and BC should be confirmed in a larger randomized study, but may represent a risk in underdeveloped countries, where GC therapy is mandatory for post-MI inpatients.

Наявність ожиріння у хворих на ішемічну хворобу серця призводить до її прогресування і підвищення смертності. З метою дослідження взаємозв'язку між мозковим натрійуретичним пептидом і структурно-функціональними параметрами серця у 69 хворих на хронічну серцеву недостатність ішемічного генезу, що асоційована з надмірною масою тіла та ожирінням, за допомогою еходопплеркардіографії й імуноферментного аналізу вивчили структурно-функціональні особливості ремоделювання міокарда лівого шлуночка і рівень N-кінцевого фрагмента мозкового натрійуретичного пептиду. Встановили, що у хворих на хронічну серцеву недостатність з ожирінням у порівнянні із групами нормальної і надлишкової маси тіла визначають нижчі рівні NT-proBNP незалежно від функціонального класу. Рівень NT-proBNP у хворих на хронічну серцеву недостатність з ожирінням має вірогідний взаємозв'язок зі структурно-геометричними параметрами серця, які характеризують процеси ремоделювання міокарда лівого шлуночка переважно концентричного типу і діастолічну дисфункцію за типом порушення релаксації.

The aim of the work is to assess dynamic changes in heart rate variability (HRV), central hemodynamics and physical performance in female swimmers at a distance of 50–200 meters and female runners at a distance of 400 meters in the preparatory and competitive periods of the training process. Materials and methods. At the beginning of the preparatory period and at the end of the competitive period, 11 female swimmers were examined, including 1 athlete – Master of Sports of Ukraine (MSU), 7 athletes – Candidate Masters of Sports (CMS), 1 – first-class athlete, 2 – second-class athletes, and 22 female runners, including 1 athlete – Master of Sports of Ukraine of International Class (MSUIC), 3 athletes – Candidate Masters of Sports, 7 first-class athletes, 8 – second-class athletes and 3 – third-class athletes. Time- and frequency domain methods of HRV analysis were used to assess the mechanisms of heart neurohumoral regulation. Central hemodynamic parameters were examined by an automated tetrapolar rheography according to W. Kubiček et al. (1970) modified by Yu. T. Pushkar et al. (1970). Physical working capacity (PWC) was measured using a submaximal PWC170 test. The functional state index (FSI) was calculated according to the formula that we had proposed and patented. Results. Analysis of HRV indices in female swimmers revealed the prevalence of parasympathetic influences in the competitive period. There was a central hemodynamics-related significant decrease in cardiac index (CI) in the competitive period, although its value corresponded to the eukinetic circulatory type (CT). The ratio of CTs was 18.2 %: 81.8 %: 0.0 %, hypokinetic, eukinetic and hyperkinetic CT, respectively, indicating a tendency towards eukinetic CT prevalence over hypokinetic one (P = 0.075) and the absence of athletes with physiologically unfavorable hyperkinetic CT. The PWC170/kg value increased by an average of 12.44 %, from 12.860 ± 0.732 kgm·min-1·kg-1 to 14.460 ± 0.823 kgm·min-1·kg-1 (P = 0.002), and FSI – of 22.21 % (P = 0.0005) and corresponding to “below average” score. In the competitive period, 2 CMS female athletes qualified for MSU, 1 first-class athlete qualified for CMS, and 2 second-class athletes achieved the first-class sport qualification. Conclusions. Female swimmers demonstrated the significant prevalence of parasympathetic effects of the ANS, the tendency towards the eukinetic CT predominance and the absence of hyperkinetic CT, significantly increased PWC170/kg value by 12.44 % and FSI – by 22.21 % in the competitive period as compared with the preparatory period. The correlation analysis to assess both periods revealed the important relationship between heart rate (HR) and autonomic rhythm index (ARI), HR and indicator of the adequacy of regulation processes (IARP), indicating that training-induced bradycardia shifted the autonomic balance towards the predominance of the parasympathetic arm of the ANS. Decreased ARI caused the decrease in СI, resulting in the transformation of hyperkinetic CT into eukinetic one and the absence of physiologically unfavorable hyperkinetic CT in the athletes. The increased functional state of female swimmers in the competitive period helped to achieve improvements in their athletic performance.