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Purpose. The purpose of this paper is to include comparison of results of the modeling and calculation in the Mentor Siemens software MotorSolve and experiment of the brushless permanent magnet motor. Methodology. Numerical investigation using licensed software MotorSolve is performed. Calculations of motor parameters and characteristics are made using Finite Element Method. The experimental investigations were made on the hysteresis dynamometer AHD-603. Results. The results of the investigations show that the calculations of the parameters and characteristics of the motor in MotorSolve software almost match with the results of the experiments. Practical value. The high efficiency of the MotorSolve software for the modeling, calculation and research of the brushless permanent magnet motors are confirmed.

Aim. To evaluate the long-term impact of endovascular left atrial appendage occlusion (LAAO) on heart failure (HF) course in patients with atrial fibrillation (AF).Materials and Methods: The prospective cohort study included patients with AF, HF, and a high risk of thromboembolic events, of which 39,6% underwent LAAO, 60,4% — received standard preventive therapy for cardioembolic events. Changes in BNP levels in the LAAO and control groups were analyzed throughout the observation period. The incidence of unfavorable HF outcomes (decompensated HF, hospitalizations related to HF, worsening HF class) was compared using the Cox-regression analysis with the log-rank test. A univariate analysis using Cox regression was conducted to identify independent predictors of endpoint achievement, involving all clinical and historical factors. Subsequently, a multivariate analysis was carried out, with predictors selected through the Wald exclusion test from those factors with a p-value less than 0.2 in the univariate analysis. Each factor was found to be a statistically significant independent predictor of the endpoint, with the overall model significance of p

Aim. To study the outcomes frequency and structure in patients with atrial fibrillation (AF) depending on the cardioembolic events preventing method: left atrial appendage (LAA) isolation, direct oral anticoagulants (DOACs) or warfarin.Material and methods. A prospective observational study included patients with AF and high risk of cardioembolic complications and without contraindications to anticoagulants. Patients who refused long-term oral anticoagulants taking underwent LAA isolation, the rest of the patients received DOACs or warfarin. The observation period was 3 years. Mortality, cardioembolic complications and major bleeding (according to GARFIELD criteria) cumulative incidence was assessed.Results. We included 245 patients: 46 patients were treated with LAA isolation, 100 with warfarin, and 99 with DOACs. Multivariate regression analysis demonstrated a statistically significant advantage of LAA occluder in terms of combined endpoint achieving frequency compared to warfarin (hazard ratio [HR] 3.10; 95% confidence interval [CI] 1.01-9.54; p=0.049), and to DOACs (HR 3.44, 95% CI 1.15-10.29; p=0.027). A similar result was obtained for all-cause mortality (HR 5.24; 95% CI 1.12-24.55; p=0.036 and HR 5.58; 95% CI 1.22-25.49; p=0.027, respectively). There were no significant differences in bleeding rates between the groups.Conclusion. This observational study demonstrates the superiority of LAA isolation as a first-line therapy over DOACs and warfarin in patients with AF and high risk of cardioembolic complications. Randomized trials are required to confirm these observations.

Aim. To identify risk factors for low adherence and develop a scale for its pre­diction. To evaluate the association of the predictive score with actual low adherence according to the 8-item Morisky Medication Adherence Scale, self-drug withdrawal, and adverse outcomes in patients with atrial fibrillation (AF).Material and methods. The study included patients with AF and a high risk of thromboembolic events according to the CHA2DS2-VASc scale, who were hospitalized from January 2011 to December 2017. Potential risk factors for non-adherence, selected from the literature, were tested in a multivariate regression analysis followed by the development of an adherence prediction scale. The asso­ciation of predicted low adherence with actual adherence was assessed.Results. The study included 199 patients. The analysis identified following predictors of low adherence: low income, history of bleeding, prior stroke, 4 positive responses to the adherence questionnaire, warfarin. Based on these predictors, a scale for predicting adherence was developed, while a threshold value of 3 points was identified (sensitivity, 90,2%, specificity, 98,4%). A significant association of low predicted adherence on the developed scale with actual adherence and adverse outcomes was demonstrated.Conclusion. We have developed a scale for predicting adherence to anticoagulant therapy, and also determined its threshold value. In case of a high risk of low adherence, clinicians should try to increase adherence in order to prevent comp­lications.

Objective: comparison of general anesthesia (GA) and intravenous conscious sedation during left atrial appendage occlusion (LAAO).Materials and Methods. The study included 120 patients from LAAO Register at the National Medical Research Center of Cardiology, who were divided into GA (n = 100) and intravenous sedation (n = 20) groups. In-hospital outcomes were assessed, as well as outcomes and data of transesophageal echocardiography (TEE) at 45 days and 6 months.Results. 3 patients required intraoperative conversion of the anesthetic method to GA. The duration of the procedure, the time of fluoroscopy, the amount of contrast medium, and the technical success did not differ signifcantly between the two groups. The incidence of in-hospital complications in the GA group was 10%, and 15% in the intravenous sedation group (p = 0.453). There were no statistically signifcant differences between the groups in long-term outcomes and TEE data after 45 days and 6 months.Conclusion. Combined intravenous sedation with local anesthesia is an effective and fairly safe method of anesthesiological support for implantation of the occluder of the left atrial auricle. It can be used in patients with a high risk of GA, with predictable difculties of tracheal intubation, as well as if the patient wishes accordingly. The limitations of the use of intravenous sedation in combination with local anesthesia are anatomical variants of SFM that are difcult for occluder implantation, as well as the patient's low tolerance to ECG in consciousness.

Aim. To compare the incidence of thromboembolic and hemorrhagic events after left atrial appendage occlusion (LAAO) or without prevention of thromboembolic events (TEEs) during prospective follow-up of patients with atrial fibrillation (AF) and a high risk of ischemic stroke (IS) who have contraindications to long-term anticoagulant therapy.Material and methods. The study included 134 patients with AF, a high risk of IS, and contraindications to long-term anticoagulation. Patients were divided into 2 groups as follows: the first group included patients who underwent LAAO (n=74), while the second one — those who did not undergo any TEE prevention (n=60). The follow-up period was 3 years. The cumulative rate of all-cause mortality, IS, transient ischemic attacks (TIA), and systemic embolism (SE) was taken as the primary efficacy endpoint. The primary safety endpoint included major bleeding according to GARFIELD registry criteria.Results. The rate of composite efficacy endpoint in the LAAO group was significantly lower than in the group without thromboembolic prophylaxis (5,2 vs 17,4 per 100 patient-years; adjusted odds ratio (OR), 4,08; 95% confidence interval (CI): 1,7-9,5; p=0,001). The rate of major bleeding was comparable in both groups (2,4 in the LAAO group vs 1,3 per 100 patient-years in the group without thromboembolic prophylaxis; adjusted OR, 0,55; 95% CI: 0,1-3,09; p=0,509). In addition, the event rate of net clinical benefit (all-cause mortality + ischemic stroke/TIA/SE + major bleeding) in the LAAO group was also significantly lower (5,9 vs 18,2 per 100 patient-years; adjusted OR, 3,0; 95% CI: 1,47-6,36; p=0,003).Conclusion. Among patients with AF and contraindications to long-term anticoagulation after 3 years of follow-up, LAAO demonstrated the significant reduction of cumulative rate of all-cause mortality and non-fatal thromboembolic events. At the same time, the frequency of major bleeding was comparable between the groups, even taking into account access-site bleeding and postoperative antithrombotic therapy (ATT)-associated bleeding in the LAAO group. Further randomized clinical trials are required to confirm these data.