Novel coronavirus infection has become one of urgent health problems of the 21st century. The associated disorders often result in the development of cardiopulmonary pathology, which requires creation of a new paradigm in diagnosis and treatment. Studies performed during the pandemic have demonstrated an important role of echocardiography (EchoCG) in diagnosis of right ventricular (RV) dysfunction in patients with respiratory insufficiency in COVID-19. The analysis of EchoCG parameters with a high prognostic value showed that in EchoCG, a special attention should be paid to right heart dimensions, RV contractility, and pulmonary artery (PA) systolic pressure, which are the most sensitive indexes of RV afterload and indirect markers of pulmonary disease severity. RV FAC can be recommended for evaluation of the RV systolic function as the most informative variable. Also, it was demonstrated that the RV longitudinal strain has an additional significance for early identification of signs of systolic dysfunction and risk stratification in patients with COVID-19. In addition to the effectiveness and reproducibility of this method, an important advantage of EchoCG is its availability, possibility of saving images for remote interpretation by other specialists, and tracking changes in morphological and functional parameters of the heart. Thus, the analysis of international literature suggests that EchoCG plays an important role in prediction of severe cardiopulmonary disorders and timely selection of the treatment for patients with COVID-19. For these reasons, EchoCG should serve as an additional method of clinical evaluation, particularly in persons with moderate or severe disease.

Aim      To evaluate the incidence of prolonged corrected QT interval (QTc) by remote single-channel electrocardiogram (ECG) monitoring in primary oncological patients with elective polychemotherapy (PCT).

Material and methods  This study included 49 oncological patients with elective PCT. A single-channel portable CardioQVARK electrocardiograph was used to record single-channel, one-lead ECG between the first and second courses of PCT.

Results Analysis of QTc interval detected a prolonged QTc interval >500 msec in 8.2 % of cases, prolonged QTc >480 msec in 18.3 % f cases, and prolonged QTc interval >60 msec compared to baseline in 12.2 % of cases.

Conclusion      Remote recording of single-channel ECG using a portable electrocardiograph is an effective method for recording and detecting various forms of heart rhythm disorders.

Aim      To analyze the cost-effectiveness of pneumococcal vaccination in 40- and 65-year-old patients with chronic heart failure (CHF).

Material and methods  Analysis was performed by Markov modeling from the perspective of the healthcare system. The evaluation was based on Russian epidemiological data taking into account results of international studies. The analyzed schedule of vaccination included one dose of 13-valent pneumococcal conjugate vaccine (PCV13) followed by 23-valent polysaccharide vaccine (PPSV23) after one year and vaccination with only one dose of PCV13. The time horizon of the study was 5 years. Costs and life expectancy were discounted at 3.5% per year.

Results The cost-effectiveness of vaccination for both 65-year-old and 40-year-old CHF patients is very high: the incremental cost of one additional QALY (Quality-Adjusted Life Year) for PCV13+PPSV23 vaccination is 113.24 thousand rubles, while vaccination with PCV13 entails a reduction in costs by 556.50 rubles per one vaccinated patient. For vaccination of 40-year-old CHF patients with PCV13+PPSV23, the incremental costs per 1 QALY will be 519.72 thousand rubles, while for vaccination with PCV13 it will be 99.33 thousand rubles.

Conclusion      Pneumococcal vaccination of CHF patients reduces the associated morbidity and mortality and is highly cost effective.

Aim      Comparative analysis of the effectiveness of a new approach, "SMART rehabilitation of patients after heart valve replacement", which includes, in addition to face-to-face training, Internet technologies in the form of video conferencing, the mobile application "Calculation of the warfarin dose", and a traditional program for educating patients after correction of valvular defects.

Material and methods  The study included 190 patients with prosthetic heart valves. The main group consisted of 98 patients who completed a distance learning course. The control group included 92 patients participating in face-to-face training. Clinical and instrumental examinations (electrocardiography, echocardiography, determination of international normalized ratio (INR)), and surveys to evaluate awareness, compliance with treatment, and quality of life (QoL) were performed.

Results At baseline, the awareness, compliance and QoL did not differ between the compared groups. After 6-month follow-up, the mean score of awareness increased by 53.6 % (р=0.0001). The compliance with treatment increased 3.3 times in the main group and 1.7 times in the control group (p=0.0247). Patients of the main group were more prone to self-management (p=0.0001), had better medical and social awareness (p=0.0335), medical and social communicability (p=0.0392), confidence in the therapeutic strategy of the attending physician (p=0.0001), and treatment effectiveness (p=0.0057). Analysis of QoL showed increases in living activity 2.1 times (р=0.0001), social functioning 1.6 times (р=0.0001), and mental health 1.9 times (р=0.0001).

Conclusion      The novel approach of distance learning, "SMART rehabilitation of patients after heart valve replacement", provides improvements in awareness, compliance with treatment and QoL.

Aim      Evaluating the redox potential of white blood cells (WBC) in acute coronary syndrome (ACS) depending on the presence or absence of type 2 diabetes mellitus (DM2).

Material and methods  The study included 100 men and women aged 35 to 65 years who were managed for ACS at the Primary Vascular Department (PVD) of the Vladivostok Clinical Hospital #1. The control group consisted of 30 healthy volunteers matched with ACS patients in major anthropometric characteristics. Examinations were performed according to clinical recommendations. Blood was withdrawn for measuring cell activity of enzymes (superoxide dismutase, SOD; succinate dehydrogenase, SDH; and glutathione reductase, GR) and serum concentration of malonic dialdehyde (MDA). Based on the ACS type, all patients were divided into 3 main ACS groups, and then the groups were subdivided into subgroups based on the presence of DM2.

Results Development of ACS was associated with changes in WBC redox potential. These changes were characterized by a significant decrease in SDH activity in all ACS patients, irrespective of their ACS type, and a moderate decease in GR in patients with myocardial infarction compared to patients with unstable angina and healthy volunteers. At the same time, the SOD activity and MDA concentration were practically unchanged compared to the control group. There were practically no significant differences in the enzyme activities between the ACS subgroups with or without DM2.

Conclusion      The WBC activities of SDH and GR on day 1 of ACS can be considered as the indicators for early diagnosis of mitochondrial dysfunction resulting from the cardiovascular catastrophe as well as the markers for impaired primary cell defense. MDA and SOD values are not informative for determining the intensity of oxidative stress and further damage of the antioxidant system.

Background    Very short-lasting episodes of AF-like activity (micro-AF) may be precursors of undiagnosed silent episodes of atrial fibrillation. In this study, we examined the relationship between increased left atrial sphericity index (LASI) and stroke in patients with micro-AF.
Material and Methods    A total of 100 consecutive patients with micro-AF enrolled in this study. The histories, cranial magnetic resonance, and computed tomography images of these patients were scanned from the hospital database. The patients were divided into two groups according to whether or not they had a stroke. LASI was calculated as a fraction of the left atrial maximum volume to the left atrial volume of the sphere in a 4‑chamber view. Atrial electromechanical delay (AEMD) intervals were calculated from the atrial wall and atrioventricular valve annulus levels by using tissue Doppler imaging (TDI). These two groups were compared in terms of stroke predictors.
Results    A history of stroke was present in 25 (25 %) patients diagnosed with micro-AF (Group 1). 75 patients did not have stroke (Group 2). There was a significant difference between the two groups in terms of left atrial lateral wall electromechanical delay (LA lateral AEMD) times, left atrial volume index (LAVI), and left atrial sphericity index (LASI). Findings: LAVI, 40.9±3.72 vs. 29.9±3.84, p<0.001; LASI, 0.84±0.07 vs. 0.66±0.07, p<0.001; LA lateral AEMD, 77.2±4.85 vs. 66.5±3.66, p<0.001.
Conclusions    Stroke precautions should be taken in patients with micro-AF. New predictive indexes should be given importance. Changes in LASI, LAVI and LA lateral AEMD values may be a predictor of stroke in patients with micro AF.

Aim    The aim of this study was to determine the average minimum number of slow pathway ablation procedures required to reach a steady success rate among inexperienced operators.
Material and Methods    We analyzed the consecutive AVNRT ablation procedures of three inexperienced operators for the rate of operational success and complications.
Results    Operators performed a total of 156 AVNRT ablation procedures. There was no statistical significance between the three operators regarding the rate of success (p=0.69) and complications. There were significant differences between the operators in terms of procedure time, fluoroscopy time, and cumulative air kerma. The variability of procedure time and cumulative air kerma, both among three operators and within each operator, decreased significantly after the 25th case. Each operator was analyzed individually for the probability of success as related to the cumulative number of ablations. All trainee operators reached a success rate of 90 % at the 27th procedure.
Conclusion    An average of 27 slow pathway ablation procedures should be performed by a beginner operator to achieve proficiency.

Objective    To examine the effect of Human Amnion-Derived Multipotent Progenitor (AMP) cells and their novel ST266 secretome on neointimal hyperplasia after arterial balloon injury in rats.
Material and Methods    Sprague-Dawley male rats were randomly divided into four groups (n=7): Control (PBS) group, systemic ST266 group, systemic AMP group and local AMP implant group. Neointimal hyperplasia was induced in the iliac using a 2F Fogarty embolectomy catheter. After surgery, the rats in the ST266 group were treated with 0.1, 0.5, or 1ml ST266 iv daily. In the systemic AMP groups, a single dose (SD) of 0.5 ×106 or 1×106 AMP cells was injected via the inferior vena cava after arterial balloon injury. In local AMP implant groups, 1×106, 5×106, or 20×106 AMP cells were implanted in 300 µl Matrigel (Mtgl) around the iliac artery after balloon injury. The iliac arteries were removed for histologic analysis at 28 days after the surgery. Re-endothelialization index was measured at 10 days after balloon injury.
Results    ST266 (1 ml) group had a lower level of the Neointima / Neointima+Media ratio (N / N+M) 0.3±0.1 vs 0.5±0.1, p=0.004) and luminal stenosis (LS) percentage (18.2±1.9 % vs 39.2±5.8 %, p=0.008) compared with the control group. Single-dose AMP (1×106) decreased LS compared to the control group (19.5±5.4 % vs 39.2±5.8 %, p=0.033). Significant reduction in N / N+M were found between implanted AMPs (20×106) and the control group (0.4±0.1 vs 0.5±0.1, p=0.003) and the Mtgl-only group (0.5±0.1, p=0.007). Implanted AMPs (20×106) decreased the LS compared with both the control (39.2±5.8 %, p=0.001) and Mtgl-only group (37.5±8.6 %, p=0.016). ST266 (1 ml) significantly increased the re-endothelialization index compared to the control (0.4±0.1 vs 0.1±0.1, p=0.002).
Conclusion    ST266 and AMP cells reduce neointimal formation and increase the re-endothelialization index after arterial balloon injury. ST266 is potentially a novel, therapeutic agent to prevent vascular restenosis in human.

Aim    Triglyceride glucose index (TyG index) is a surrogate marker for insulin resistance. No studies have evaluated the TyG index in patients with coronary slow flow phenomenon (CSFP). We investigated TyG index values in CSFP and evaluated whether it had a predictive value for the diagnosis of CSFP.
Material and Methods    132 CSFP patients and 148 subjects with normal coronary arteries were included in the study. Thrombo­lysis in myocardial infarction frame count (TFC) of each patient was calculated. Demographic, clinical features, information regarding medication use and biochemical variables of the patients were obtained from hospital records.
Results    TyG index of patients with CSFP and normal coronary flow were 9.02 (8.65–9.42) and 8.69 (8.39–9.18), respectively (p<0.001). Mean TFC showed positive correlation with the TyG index, glucose, triglyceride, and hemoglobin concentration (r=0.207, r=0.138, r=0.183, r=0.179 and p<0.001, p=0.020, p=0.002, p=0.003, respectively) and negative correlation with high density lipoprotein-cholesterol (HDL–C) level (r=–0.292, p<0.001). Receiver operating characteristic curve analysis of TyG index demonstrated that the value of 8.68 predicted CSFP curve analysis of TyG index demonstrated that the value of 8.68 predicted CSFP with sensitivity of 74.2 % and specificity of 58.6 %. In multivariate logistic regression analysis, HDL–C, hemoglobin and the TyG index were the independent predictors of CSFP.
Conclusions    Our findings supported the hypothesis that insulin resistance play role in CSFP.

Studying the key mechanisms of cardiovascular diseases has opened new possibilities for the pharmacological impact on the pathophysiological mechanisms of heart failure (HF). The signaling pathway, nitric oxide – soluble guanylate cyclase – cyclic guanosine monophosphate (NJ-sGC-cGMP), provides normal functioning of the cardiovascular system in healthy people and serves as a potential target for medicines in HF with reduced ejection fraction (HFrEF). In HFrEF progression, the sGC activity decreases due to endothelial dysfunction and oxidative stress. The increased synthesis of cGMP resulting from sGC stimulation can restrict myocardial fibrosis, reduce stiffness of the vascular wall and induce vasodilation; in this process, the mechanism of action of sGC stimulators does not overlap with other therapeutic targets. According to the results of the international randomized clinical study VICTORIA, the use of the sGC stimulator, vericiguat, in patients with HF, ejection fraction <45%, and a recent episode of decompensation in their history reduced the risk of repeated hospitalization and cardiovascular death. Also, this treatment was characterized by a favorable safety profile when added to standard therapy.