Introduction. The lecture covers the current state of issues regarding the etiology, pathogenesis, diagnosis, classification, and treatment of infective endocarditis (IE), the acute, especially staphylococcal untreated cases of which are absolutely lethal. Attention is drawn to a significant increase in the incidence of IE in recent decades.

Etiology. Currently, more than 130 causative agents of IE have been identified, belonging to bacteria and fungi. Risk factors include pre-existing conditions, interventional diagnostic studies, cardiac surgery and endovascular interventions, programmed hemodialysis, injection drug use, immunosuppressive therapy, and advanced age. IE of implantable devices is becoming increasingly important.

Three components are necessary for infective endocarditis: the presence of a pathogen, tissue damage (heart valve or endocardium), and a weakened immune system.

Pathogenesis. Damage to the layer of endothelial cells of the endocardium causes rapid platelet adhesion and fibrin deposition. Microorganisms readily settle on this clot, grow rapidly, leading to IE.

Clinical Picture. The most serious organ pathology is primarily cardiac. IE leads to destruction and insufficiency of valves, impaired intracardiac hemodynamics, heart failure, possible myocarditis, pericarditis, and myocardial infarction.

The most formidable and frequent manifestation of IE is thromboembolic complications, ischemic stroke, glomerulonephritis.

Diagnosis. Major and minor diagnostic criteria are used: major criteria include positive microbiological blood tests and imaging results; minor criteria include a history of cardiac pathology, marked fever, vascular, and immunological phenomena. Combinations of criteria are the basis for a diagnosis of definite or probable IE. Patients with IE often enter the clinic already in the stage of organ damage, demonstrating different masks – cardiac (acute myocardial infarction, angina pectoris, arrhythmia), cerebral (ischemic stroke), renal, vascular, and pulmonary forms.

Treatment. Treatment of infectious endocarditis includes etiotropic antimicrobial pharmacotherapy, correction of hemostasis, immunological and other complications, surgical methods, and sanitation of foci of chronic infection. All patients diagnosed with IE are urgently admitted.

Wide application of intravital methods of visualization of internal cardiac structures in clinical practice allows identifying anatomical features of the organ structure and pathological intracardiac formations. Due to heterogeneity and variability of intracardiac formations found in a normal heart, difficulties arise in differential diagnostics with pathological formations (thrombus, tumor) and decision on further tactics. Normal intracardiac structures are usually not accompanied by pathological clinical manifestations, they are discovered during life by chance or during autopsy, however, occasionally their topographic and morphological variants cause cardiac arrhythmias or thromboembolism. To prevent false diagnoses in the development of pathological symptoms, other structural heart diseases (ischemic heart disease, cardiomyopathy, myocarditis, etc.) are excluded. The main available method for studying intracardiac structures and minor cardiac anomalies is transthoracic echocardiography, the results of which are supplemented by transesophageal examination, if necessary – computed tomography and magnetic resonance imaging. In case of arrhythmic syndrome, an electrophysiological study is performed to establish the causes of arrhythmia. Multimodal visualization using modern research methods, electrophysiological study and knowledge of the topography of anatomical variants of internal structures and minor anomalies of the heart will allow timely differential diagnostics and planning of further treatment or observation tactics.

Background. Today, the use of selective embolization of blood vessels become widespread in combating obstetric and gynecological bleeding, including as one of the steps during surgical delivery in cases of abnormal invasive placenta. There is a need to develop precise angiographic criteria for predicting bleeding risks and choosing further tactics when placenta invasion is detected.

Aim: To identify angiographic criteria for various forms of placental invasion.

Material and Methods. The study included 59 pregnant women with a uterine scar and complete placenta previa, who underwent cesarean section at different gestational ages, with the use of uterine artery embolization due to signs of placental invasion detected during antenatal ultrasound. Subtraction angiograms obtained during selective uterine artery angiography were analyzed.

Results. In the group with complete placental invasion, the most specific criteria included: contrast enhancement of vascular lacunae groups or one exceeding 1/5 of the entire placental zone (95%) with positive predictive value (PPV) of 90%, early shunting venous drainage from the placental bed (100%) with PPV 100%, detection of limited arteriovenous shunt in the form of microfistulous arteriovenous malformation (AVM) (95%) with PPV 83.3%, detection of diffuse arteriovenous shunt as macrofistulous AVM (100%) with PPV 100%. Correspondingly, the most accurate diagnostics of complete placental invasion demonstrated: contrast enhancement of vascular lacunae groups or one exceeding 1/5 of the placental zone (93.3%), early shunting venous drainage (96.7%), detection of limited AV shunt (80%), detection of macrofistulous AVM (96.7%).

Conclusions. Identification of several criteria with high levels of specificity, accuracy, and PPV: contrasting groups of vascular lacunae with either one area of more than 1/5 of the entire placentation zone, early bypass venous discharge from the placental site, identification of a limited and diffuse arteriovenous shunt in the form of a macroor microfistulous AVM is most likely to indicate the presence of complete or partial ingrowth. In the absence of the above signs and the identification of low-specific criteria (dilation of the arterial bed of the placental lobules (less than 1/5 of the entire placental area), contrasting single vascular lacunae in the placental area, while maintaining normal venous discharge of venous outflow) is most likely to indicate the absence of complete and partial placental ingrowth.

Adipose tissue is attracting more and more attention of researchers from the position of an endocrine organ that implements its functions through a wide range of biomolecules called adipokines (adipocytokines). The dysfunction of adipose tissue with obesity leads to pathological secretion of these biomolecules, which causes the development of cardiovascular diseases of atherosclerotic genesis, type 2 diabetes mellitus, dyslipidemia. The review presents the latest data on the main adipose tissue depots, their cellular composition, key functions, as well as recent studies in the field of metabolic activity of adipose tissue of various localizations. PubMed and Google Scholar databases were used to search for literature. Studies conducted on patients over the age of 18 were included. The analysis did not include reviews, animal studies, drug studies, and the effects of diet and surgical treatment of obesity were not evaluated.

Background. Early detection of left ventricular adverse remodeling and its predictors can improve the accuracy of postoperative monitoring and optimize personalized treatment strategies for high-risk patients. A promising approach is radiomics – a high-level medical image processing method that converts imaging data into quantitative indicators for precise characterization of pathological tissue changes.

Aim: To investigate radiomic features prognostic value based on noncontrast cine cardiac magnetic resonance imaging (MRI) for assessing the risk of adverse left ventricular remodeling in patients with ischemic cardiomyopathy.

Material and Methods. This observational, cohort, retrospective, single-center study included patients (n = 44, 59.2 ± 8.1 years old) with an established diagnosis of ischemic cardiomyopathy (ICM) and indications for surgery. Preoperatively, all patients underwent cardiac MRI with according to clinical indications (to assess myocardial viability). In the early postoperative period and one year after surgery, all patients underwent echocardiography. The criterion for continued LV remodeling was an increase in end diastolic volume ≥10% one year after surgery according to echocardiography. Two study groups were formed: group 1 (n = 23) – patients with ICM without LV aneurysm, who underwent isolated coronary artery bypass grafting; group 2 (n = 21) – patients with ICM and LV aneurysm, who underwent coronary artery bypass grafting in combination with aneurysmectomy and LV plastic surgery. The control group included 28 patients without morphofunctional and structural changes in the LV myocardium according to contrast-enhanced cardiac MRI. Radiomics analysis was performed on noncontrast cine cardiac MRI images at end-diastole.

Results. Texture analysis was performed on 72 regions of interest in cine images, corresponding to areas of visually intact myocardium on post-contrast images in patients with ICM (n = 44) and to areas of myocardium in patients in the control group (n = 28). In a year after surgery, continued LV remodeling was detected in 12 patients: 6 patients in groups 1 and 2, respectively. The highest number of statistically significant features with high and moderate predictive ability were identified in the group of patients with ICM and LV aneurysm who underwent a combined procedure – coronary artery bypass graft combined with aneurysmectomy and LV reconstruction. In contrast, in the group of patients who underwent coronary artery bypass graft alone, radiomic features demonstrated low differentiating ability. The most significant radiomic features belong to the category of second-order features: GLRLM (Run Percentage), GLSZM (Zone Percentage) and GLDM (Dependence Non Uniformity Normalized).

Conclusion. Non-contrast cine cardiac MRI Radiomics is a promising tool for stratifying the risk of adverse LV remodeling in patients with ICM, particularly after combined surgical procedures. Further development and validation of these approaches may facilitate personalized patient management and improve long-term clinical outcomes.

Introduction. Atrial fibrillation (AF) is a common and complex problem in patients with heart failure (HF). At the same time, AF and HF form a synergistic interaction. Cardiac resynchronization therapy (CRT) is an effective method of treating certain groups of patients with HF. In view of this fact, the negative dynamics of echocardiographic parameters in patients with effective CRT and nonparoxysmal AF is of interest for study.

Aim: To assess impact of non-paroxysmal AF on clinical and echocardiographic parameters in CRT responders at the late postoperative period.

Material and Methods. A single-center retrospective observational study was performed on 608 patients who underwent primary implantation of the CRT (-R / -D) between 2009 and 2022. The response to CRT was assessed at the time of the best dynamics of the parameters. 139 patients were selected. All patients with non-paroxysmal AF underwent radiofrequency ablation (RFA) of the atrioventricular node. Two groups of patients were formed based on this criterion. The primary endpoint was all-cause mortality in the long-term follow-up period.

Results. Descriptive statistics did not reveal a significant intergroup difference in demographic and basic clinical characteristics (p > 0.05), with the exception of a higher incidence of TIA/He also has a lower functional status in the group with AF. The results of echocardiographic data in the preand postoperative periods differed in most linear and volumetric parameters, with the exception of finite diastolic volume (CDV) and LVEF. In the sinus rhythm group, there was a statistically significant decrease in the incidence of severe valvular insufficiency, as well as significantly lower atrial volume and size of the right heart (p < 0.05). Postoperative analysis revealed positive dynamics of most parameters in both groups, however, there was no significant dynamics in the size of the pancreas and the TP gradient. In the long-term period, intergroup differences in LVEF, CDOs, and MR degree did not reach statistical significance, however, patients after RF AB connection had large right heart chambers. A single-factor analysis revealed statistically significant associations of overall mortality with art. (OR = 6.0; 95% CI 1.1–32.5), TR 3 art. (OR = 8.7; 95% CI 1.3–57.0) and MR 3 art. (OR = 9.6; 95% CI 2.9–31.7). According to the results of multifactorial regression analysis, the presence of severe MR in the preoperative period was associated with an increased chance of mortality (OR = 7.2; 95% CI 1.7 – 30.1). The overall mortality rate was 19.4% (n = 27), and there was no intergroup difference in long-term survival (p = 0.202).

Conclusion. Linear and volumetric parameters of the right heart chambers in CRT responders with nonparoxysmal AF were higher than those in patients with sinus rhythm. This group was more likely to have significant regurgitation of both AV valves, which persisted into the long-term follow-up. The association between AF and long-term all-cause mortality did not reach statistical significance.

Introduction. Cardiac magnetic resonance (CMR) is the gold standard for assessing myocardial remodeling after myocardial infarction. Particular attention is paid to myocardial tissue characteristics assessed using late gadolinium enhancement (LGE). Textural heterogeneity parameters of LGE are a novel quantitative metric that reflects the structural heterogeneity of left ventricular (LV) myocardial tissue changes.

Aim: To investigate the association between textural parameters, assessed by quantitative analysis of signal intensity heterogeneity on late gadolinium enhancement CMR, and the development of major adverse cardiovascular events (MACE) in patients with acute myocardial injury.

Material and methods. This retrospective study included 108 patients admitted to the emergency cardiology department with a diagnosis of primary ST-elevation or non-ST-elevation myocardial infarction (STEMI or NSTEMI). A composite primary endpoint was established, which included the following clinical outcomes: cardiovascular death, all-cause death, non-fatal myocardial infarction, and non-fatal acute stroke. Inclusion criteria were: 1) performance of contrast-enhanced CMR within 4–7 days of hospitalization; 2) CMR findings consistent with acute ischemic injury of the LV; and 3) satisfactory image quality. CMR criteria for acute ischemic injury included: a high-intensity signal on T2-weighted images (T2WI) with co-localized LGE in a segment(s) demonstrating an ischemic pattern of contrast distribution. Quantitative CMR analysis was performed using the dedicated post-processing software CVI42 (Circle Cardiovascular Imaging, Canada). Myocardial texture analysis was conducted using the 3D Slicer application, version 5.2.2 (The Slicer Community, USA). For the analysis, LGE images were used. From each slice, textural features of signal intensity (SI) heterogeneity were extracted separately for the following regions of interest (ROIs): the LV myocardial injury zone, intact myocardium, and the entire LV (comprising both injured and intact myocardium).

Results. The mean age of the patients was 59.56 ± 10.7 years, with 75% (n = 81) being male. STEMI was present in 89.3% of the entire cohort. The follow-up period was 1095 ± 23 days. Follow-up data were obtained for all 108 patients (100% of the sample). Based on the occurrence of the primary endpoint, two groups were formed: the group without cardiovascular events (“–MACE”) and the group that reached the endpoint (“+MACE”). Analysis of LV myocardial tissue characteristics assessed in the LGE phase revealed no significant differences between the study groups for almost all parameters, with the exception of the global LV SI elevation on T2-WI, which was significantly lower in the “+MACE” group. Quantitative analysis of SI heterogeneity across the entire LV using textural features revealed differences in first-order statistics, with higher values of these indices in the “+MACE” group. Patients who experienced a MACE during the follow-up period were characterized by a more asymmetric and complex signal texture, featuring abrupt variations in gray-level intensity, higher gray-level irregularity, shorter lengths of homogeneous areas and run lengths, and a predominance of small heterogeneous areas. Analysis of the intact myocardium in the LV also demonstrated higher heterogeneity and gray-level irregularity, with a high number of small heterogeneous regions.

Conclusion. Heterogeneity parameters assessed by CMR reflect the changes occurring in the LV myocardium after MI, are associated with cardiac functional indices, and may be considered prognostic factors for an adverse clinical course. Given the limitations of this study, further research is needed to investigate the relationship between LV tissue characteristics on CMR, entropy, and adverse outcomes after acute myocardial injury. 

Background. Coronary microvascular obstruction (CMVO, no-reflow) syndrome develops in 5–20% of patients with myocardial infarction (MI) during percutaneous coronary intervention (PCI). The negative impact of CMVO on prognosis was known long ago. However, clinical practice in MI treatment has changed significantly. The introduction of new approaches to the prevention and treatment of CMVO requires a reassessment of its prognostic role using modern statistical methods. Furthermore, aspects such as the causes of death in patients with CMVO and the impact of this complication on radiation exposure also remain understudied.

Aim: To compare in-hospital and long-term outcomes in patient groups with MI and PCI, complicated or uncomplicated by CMVO in current clinical practice.

Material and Methods. A single-center cohort study was conducted on patients with MI and PCI, complicated or not complicated by the development of CMVO. The CMVO criteria were a TIMI flow grade of < 3 or a Myocardial blush grade of < 2. To assess patient radiation exposure during PCI, the dose area product (DAP) was analyzed. Propensity score matching was used to adjust for intergroup differences. Multivariate analysis of the risk of long-term mortality was performed using Cox regression, accounting for time-dependent effects. Kaplan – Meier curves were plotted, and the Log-rank test was used to compare survival.

Results. A total of 1264 patients were enrolled. After matching, 418 patients remained: 209 patients without CMVO and 209 with non-CMVO. In the CMVO group, the DAP was 59.9 [39.8; 94.5] Gycm², compared to 82.8 [59.2; 135.5] Gycm² in the CMVO group (p < 0.001). At the in-hospital stage, 9 (4.3%) and 22 (11.0%) patients died, respectively (p = 0.015). Long-term outcomes were tracked in 46% of patients (median follow-up 498 [294; 1001] days). In the long-term period, death was recorded in 15 (7.2%) patients in the group without CMVO and in 37 (18%) in the group with CMVO (p = 0.001). Multivariate analysis of the risk of long-term mortality was performed using Cox regression, accounting for time-dependent effects. Kaplan – Meier curves were plotted, and the Log-rank test was used to compare survival. Among the causes of long-term death, decompensation of chronic heart failure was more frequent in the CMVO group compared to the successful reperfusion group (41% vs. 0%, respectively, p = 0.002).

Conclusion. The development of CMVO during PCI in patients with MI is associated with an extremely high risk of death in the early postoperative period and leading to worse long-term survival overall. The occurrence and perioperative treatment of CMD lead to greater radiation exposure for the patient. Decompensation of chronic heart failure is the leading cause of long-term death in patients with CMD.

Introduction. Patients with coronary artery disease (CAD) have a residual risk of adverse vascular events. The multifactorial and heterogeneous nature of this risk requires an integrative approach to assessment, which is a pressing issue in cardiology. The role of lipoprotein (a) (Lp(a)) as a marker of residual risk has been demonstrated. In this article the role of advanced glycation end products (AGEs) is being investigated in the progression of residual risk in patients with CAD.

Aim: To evaluate the relationship between the autofluorescence index of advanced glycation end products and lipoprotein (a) levels to determine residual risk in patients with stable coronary artery disease and dyslipidemia receiving intensive lipid-lowering therapy.

Materials and Methods: A single-center prospective study was conducted involving 87 men aged 55 to 75 years with CAD and comorbidities. Standard laboratory tests, including Lp(a) levels, and instrumental methods in accordance with clinical guidelines were used. AGEs accumulation was also determined by calculating the autofluorescence index using the portable AGE Reader device. Dyslipidemia was corrected with a fixed combination of rosuvastatin and ezetimibe; alirocumab when indicated. The median follow-up was 12 weeks. Statistical processing was performed using StatTech 4.9.4 (StatTech LLC, Russia).

Results. Study participants were divided into subgroups based on Lp(a) levels >0.5 g/L (n = 41) and <0.5 g/L (n = 46) assessing residual risk. Lipid profile target parameters were achieved in 78.2% of patients (n = 68) with the fixed-dose combination of rosuvastatin and ezetimibe and in 21,8% (n = 19) with triple therapy, of which 17.2% (n = 15) belonged to subgroup 1 and 4.6% (n = 4) to subgroup 2. Autofluorescence index at baseline: 2.8 [2.20; 4.07]. After 6 weeks of intensive lipid-lowering therapy and adequate treatment of comorbid pathology, the autofluorescence index was 2.79 [2.12; 4.00]; after 12 weeks – 2.75 [2.02; 3.88]. According to the color identification of the device, the red autofluorescence index (very high risk) was observed in 54% of patients at the start of the study (n = 47), and after 12 weeks – in 35.6% (n = 31). The study showed a strong direct correlation with the level of AGEs at the start and after 12 weeks for the group with the Lp(a)>0.5 g/l. ROC analysis demonstrated that an increase in the autofluorescence index is a statistically significant predictor of increased residual risk (AUC = 0.976; 95% CI: 0.918–1.000, p < 0.001). The sensitivity and specificity of the predictive model were estimated at 93.3%.

Conclusions: The AGEs autofluorescence index may be used for comprehensive noninvasive assessment of residual risk in patients with stable coronary artery disease and hyperlipoproteinemia (a).

Introduction. The expansion of human fields of activity where ionizing radiation is used (nuclear energy, military affairs, nuclear medicine) poses the task of assessing the individual radiosensitivity of persons in contact or planning to associate their professional activities with the radiation factor.

Aim: To evaluate the degree of methylation of the GNAS, RABL6, RHOD genes and its association with the dose of chronic external radiation and the frequency of chromosomal aberrations in workers of the Siberian Chemical Plant who were exposed to radiation during their professional activities.

Material and Methods. The sample was made up of personnel of the Siberian Chemical Plant, who in the course of their professional activities were not exposed (control group, n = 38) or were exposed (study group, n = 98) to chronic exposure to ionizing radiation at doses from 10 to 656 mSv. The degree of gene methylation was assessed using real-time methyl-sensitive PCR. The frequency of chromosomal aberrations was assessed using a routine cytogenetic method without karyotyping, using Giems dye.

Results. It was found that the degree of methylation of GNAS, RABL6 and RHOD between the control group and the study group did not differ statistically (р > 0.05). However, it is noted that women are older than men in both groups. The frequency of dicentric chromosomes in women in the study group is lower, which may be explained by their lower age compared to the control group and (or) exposure to gamma radiation in “small” doses. There was no correlation of the degree of methylation of the studied genes with an external radiation dose of 10–656 mSv and the frequency of chromosomal aberrations in men.

Conclusion. An additional study of the degree of methylation of GNAS, RABL6 and RHOD at high doses of external exposure to gamma radiation is likely to confirm or deny the absence of a dose dependence of the degree of methylation of these genes.

Background. Advances in genomics and proteomics have facilitated the identification of numerous new candidate biomarkers for the diagnosis and prognosis of coronary heart disease (CHD), as well as for predicting adverse cardiovascular events, including post-coronary artery bypass grafting (CABG) outcomes. MicroRNAs represent a promising category of these biomarkers.

Aim: To investigate the association between the rs2910164 polymorphism in the MIR146A gene and the rs3746444 polymorphism in the MIR499A gene with adverse cardiovascular events and general inflammation markers in CHD patients post-CABG.

Material and Methods. This prospective cohort study involved 158 CHD patients with a median age of 63 years [58; 67]. Patients were assessed at three stages: preoperatively, on postoperative days 8–10, and post-discharge. Early in-hospital cardiovascular events were recorded over 8–10 days of hospitalization, and long-term events were tracked for an average of 36.1 ± 10.6 months post-CABG. Comprehensive blood analyses and leukocyte DNA genotyping were conducted preoperatively and on days 8–10 postsurgery. Additionally, flow cytometry and high-sensitivity C-reactive protein (CRP) measurement were performed on a random subset of 102 patients.

Results. The allele frequencies of G and C (rs2910164) were 0.62 and 0.38, respectively, and those of A and G (rs3746444) were 0.83 and 0.17 in the CHD cohort. No significant differences in rare allele prevalence were observed between patients with and without long-term adverse cardiovascular events. Preoperatively, CHD patients with the GG genotype of rs2910164 MIR146A displayed higher plateletplatelet aggregate counts. Post-CABG, this genotype group showed significantly elevated values in platelet-platelet aggregate mean fluorescence intensity (MFI) (33.1 [31.5; 35.75] vs. 30.0 [29.0; 33.13], p = 0.001), MFI of P-selectin-expressing platelets (4.69 [2.05; 6.77] vs. 1.97 [1.49; 2.53], p = 0.002), MFI of P-selectin-expressing platelet–monocyte (6.71 [4.18; 16.4] vs. 4.22 [3.73; 6.14], p = 0.018), and MFI of P-selectin-expressing platelet-platelet aggregates (5.17 [2.47; 7.24] vs. 2.56 [1.7; 2.94], p = 0.003). The erythrocyte sedimentation rate (ESR) was significantly higher in patients with the C allele preoperatively (60.0 [31.0; 89.0] mm/hr vs. 40.0 [27.75; 57.75] mm/hr, p = 0.043).

Conclusions. The presence of rare alleles in rs2910164 (MIR146A) and rs3746444 (MIR499A) was not associated with an increased frequency of in-hospital or long-term adverse cardiovascular events. However, CHD patients with the GG genotype of rs2910164 MIR146A post-CABG exhibited significantly higher MFI in platelet aggregates expressing P-selectin.

Acute kidney injury (AKI) remains a common and prognostically unfavorable complication of cardiac surgery in children performed under cardiopulmonary bypass (CPB). Nitric oxide (NO), a universal endogenous vasodilator and cytoprotector, has the potential to mitigate key mechanisms of AKI. However, in pediatric practice data are lacking regarding the safety and efficacy of targeted intraoperative NO delivery into the CPB circuit for AKI prevention.

Aim: To assess the safety and potential nephroprotective effect of delivering nitric oxide (80 ppm) directly into the cardiopulmonary bypass circuit during surgical correction of congenital septal heart defects in children.

Material and Methods. A pilot randomized study was conducted. Thirty patients were divided into two groups: the study group (n = 15) received 80 ppm NO during CPB, and the control group (n = 15) did not receive NO. Safety was assessed by methemoglobin levels and clinical course. Efficacy was analyzed by the dynamics of specific AKI biomarkers (NGAL, IL-18) in blood and urine before surgery, after CPB, and at 16 hours, by changes in urinary oxygen tension (PuO2), and by postoperative stratification using the pRIFLE criteria.

Results. Nitric oxide delivery into the extracorporeal circuit during cardiopulmonary bypass is recognized as safe: the methemoglobin level in the NO group did not exceed reference values (1.5% [1.35; 1.62]). No statistically significant differences were found in intraand postoperative clinical outcomes between the groups. Preliminary signs of potential nephroprotective efficacy were demonstrated: despite a comparable distribution of patients by pRIFLE stages (p > 0.05), the NO group showed significantly lower concentrations of blood NGAL after CPB (352.4 [254.3; 417.1] vs. 599 [430.6; 676.7] ng/ml, p = 0.03) and at 16 hours (p = 0.01), as well as in urine at all postoperative time points (p = 0.001). The interleukin-18 (IL-18) level at 16 hours was also significantly lower in the intervention group, both in blood (4.14 [2.49; 6.01] vs. 7.4 [4.56; 7.58] pg/ml, p = 0.02) and in urine (8.31 [7.57; 10.28] vs. 13.2 [8.57; 16.2] pg/ml, p = 0.047). The urinary oxygen tension (PuO2) after CPB was significantly higher in the NO group (138.0 [96.5; 151.6] vs. 60.7 [57.2; 97.4] mmHg, p = 0.03).

Conclusion. Intraoperative donation of nitric oxide at a concentration of 80 ppm is a safe technique in children. The obtained data on its positive effect on a panel of early renal injury biomarkers (NGAL, IL-18) and renal oxygenation (PuO2) against a comparable clinical pRIFLE profile suggest it is a promising nephroprotective method, warrants further investigation in larger trials.

Introduction. Paroxysmal supraventricular reentrant tachycardias (PSRTs) are the most common class of tachyarrhythmias in childhood. Their clinical course is characterized by marked heterogeneity. The severity of clinical manifestations depends not only on the electrophysiological properties of the arrhythmia substrate but also on the individual reactivity of the sympathetic nervous system (SNS). Despite understanding the general role of the SNS, assessing its individual contribution in a particular patient remains challenging. Beta-adrenergic reactivity of erythrocyte membranes (β-ARM) is an integral marker of β-adrenergic receptor function and assesses their functional state in vitro based on the degree of membrane stabilization under the influence of a β-blocker. An increase in β-ARM (> 20 arbitrary units) is interpreted as a sign of receptor desensitization–an adaptive response to chronic hyperstimulation, which serves as an indirect marker of prolonged sympathetic hyperactivation.

Aim: To assess β-ARM levels in children with various forms of WPW and determine their relationship with the presence, frequency, and severity of clinical paroxysms.

Material and Methods. A single-center retrospective study included 38 children aged 7 to 17 years, including 15 (Group 1) with asymptomatic WPW syndrome and 23 (Group 2) with symptomatic WPW syndrome (WPW syndrome and AVNRT). β-ARM levels were determined photometrically by in vitro inhibition of hypotonic hemolysis with a nonselective β-blocker. Clinical severity was assessed using an original scoring system. Statistical analysis included the Mann – Whitney U test, Spearman correlation, and logistic regression.

Results. The level of β-adrenergic activity of erythrocyte membranes (β-ARM) was significantly higher in children with symptomatic supraventricular reentrant tachycardias compared to asymptomatic WPW phenomenon (21.5 ± 8.9 arbitrary units vs 14.2 ± 3.5 arbitrary units; p = 0.01). Each 1% increase in β-ARM increased the odds of a symptomatic course by 2.05 times (OR = 2.05; 95% CI: 1.28–3.28; p = 0.003). Higher values of β-ARM were found in patients with paroxysms at rest (22.5 [20.8; 24.2] arbitrary units) compared to those with exercise (18.9 [16.1; 21.7] arbitrary units; p = 0.032), as well as in patients requiring drug relief (20.51 [17.70; 37.47] arbitrary units) compared to those spontaneously relieved (16.20 [10.44; 20.00] arbitrary units; p = 0.041). The most severe course, characterized by frequent, treatment-resistant, prolonged paroxysms with a high heart rate, is associated with the highest β-ARM level (32.6 [24.12; 38.62] arbitrary units; p = 0.009).

Conclusion. Elevated β-ARM levels, reflecting β-adrenergic receptor desensitization, are a statistically significant predictor of symptomatic PSRT course in children and are associated with a more severe clinical phenotype. Determination of β-ARM can serve as an additional non-invasive tool for risk stratification in children with asymptomatic WPW.

Introduction. Given the high cost of cardiac resynchronization therapy (CRT) devices, the search for reliable preoperative predictors of response to optimize patient selection becomes critically important. One promising prognostic factor is right ventricular (RV) systolic function. However, existing data are contradictory, and echocardiography does not provide an accurate quantitative assessment of right ventricular ejection fraction (RVEF) due to the chamber's anatomical peculiarities. Cardiac magnetic resonance imaging (MRI) is the gold standard for assessing RV volumes and function, but its role in predicting response to CRT has been insufficiently studied due to the limited number of existing studies.

Aim: To study the association between baseline RV EF, measured by cardiac MRI, and echocardiographic response to CRT. Material and Methods. A single-center retrospective study was conducted involving 368 patients who received a CRT-P or CRT-D (with cardioverter-defibrillator function) implant at the Federal Center for Cardiovascular Surgery (Penza, Russia) between 2014 and 2021 in accordance with current clinical guidelines and who underwent cardiac MRI immediately prior to implantation. A total of 113 patients were selected. CRT response criteria were defined as an increase in left ventricular ejection fraction (LVEF) by ≥ 5% and/or a reduction in left ventricular end-systolic volume (LVESV) by ≥ 15% from baseline. Based on response, patients were divided into two groups: responders and non-responders.

Results. The formed groups were comparable in terms of key clinical and demographic characteristics, as well as heart failure functional class, LVEF, and QRS duration. The only difference was a higher frequency of ischemic cardiomyopathy (ICM) in the nonresponder group. When comparing baseline MRI parameters, the non-responder group had significantly lower RVEF values (46 [39; 51] vs. 32 [22; 43], p = 0.001), higher right ventricular end-diastolic and end-systolic volumes, and a higher frequency of moderate (grade 2) or greater tricuspid regurgitation (TR). In the postoperative period, the groups did not differ in paced QRS duration. As expected, the groups differed significantly in LVEF and left ventricular end-diastolic volume. Univariate regression analysis identified four indicators statistically significantly associated with the endpoint: ICM (OR 0.381, 95% CI 0.157–0.924, p = 0.033), LVESV (OR 0.994, 95% CI 0.990–0.999, p = 0.011), RVEF (OR 1.060, 95% CI 0.992–1.132, p = 0.083), and TR grade ≥ 2 (OR 0.696, 95% CI 0.233–0.992, p = 0.040). Multivariate regression analysis using these indicators revealed that only two maintained a statistically significant association with CRT response: ICM (OR 0.326, 95% CI 0.115–0.924, p = 0.035) and RVEF (OR 1.057, 95% CI 1.022– 1.094, p = 0.001).

Conclusion. The study demonstrated that patients with standard indications for CRT and lower baseline RVEF measured by cardiac MRI are less likely to respond to therapy. RVEF and ICM were independently associated with CRT response: RVEF showed a direct relationship, while the presence of ICM showed an inverse relationship.

Myocardial revascularization is an important method of treating coronary artery disease (CAD) with atherosclerotic lesions of the coronary arteries. At the same time, the presence of chronic heart failure (CHF) significantly complicates the prediction of disease outcomes due to the leveling of the beneficial effect of revascularization on the incidence of cardiovascular death. To date, there is no universal algorithm for risk stratification in patients with CHF and CAD who have undergone coronary artery bypass grafting (CABG). Aim: To develop a practically-oriented algorithm for stratifying of the risk of adverse cardiovascular events in patients with CHF and CAD who have undergone CABG, taking into account all clinical, anamnestic, laboratory, and instrumental data.

Material and Methods. The study included 82 patients with CHF and CAD who underwent CABG. All patients underwent the collection of complaints, medical history, physical examination, echocardiography, general clinical laboratory examination, determination of N-terminal fragment of the brain natriuretic propeptide (NT-proBNP) level, inflammation and fibrosis biomarkers, including growth differentiation factor-15 (GDF-15), monitoring for 36 months. Development of the combined endpoint (CCT), including death from cardiovascular causes, hospitalizations for heart failure, acute ischemic events requiring revascularization and acute cerebrovascular events, was recorded. Patients were divided into two groups: group 1 (n = 45) with favorable course of disease, and group 2 (n = 37) with unfavorable course. Statistical analysis was performed using IBM SPSS Statistics version 21.

Results. An algorithm for stratifying the risk of adverse cardiovascular events within three years after CABG in patients with CHF and CAD has been developed. The main factors associated with a high risk of these events were: NYHA functional class, a history of CHF decompensation, anemia before cardiac surgery, decreased left ventricular ejection fraction less than 42%, and increased concentrations of GDF-15 and NTproBNP.

Conclusion. The proposed algorithm allows for a differentiated approach to assessing the risk of adverse cardiovascular events after CABG. A simplified version of the algorithm, excluding GDF-15 and NTproBNP, is available for widespread use in clinical practice. 

Background. Prior endovascular interventions can trigger the development of microvascular dysfunction in patients with coronary artery disease (CAD), which can negatively impact the function of coronary artery bypass grafts after surgery. Dynamic myocardial single-photon emission computed tomography (SPECT) is a promising method for the noninvasive diagnosis of these disorders.

Aim: To evaluate myocardial blood flow using SPECT in patients with multivessel coronary artery disease and prior percutaneous coronary interventions (PCI) before coronary artery bypass grafting (CABG).

Material and Methods. A single-center prospective study was conducted, including 118 patients with CAD referred for CABG. Patients were divided into two groups: the main group (n = 60) – patients with a history of prior PCI (PCI group); the control group (n = 58) – patients without previous endovascular interventions (No PCI group). All patients underwent dynamic myocardial SPECT with a pharmacological load 2 days before surgery to assess absolute parameters of myocardial blood flow (MBF) and coronary flow reserve (CFR).

Results. Global myocardial blood flow at rest did not differ between the groups. However, under stress load conditions, global MBF and CFR were significantly lower in the PCI group compared to the No PCI group: 0.79 [0.38; 1.2] ml/min/g versus 1.01 [0.55; 1.6] ml/min/g (p = 0.001) and 1.4 [0.89; 1.8] versus 1.73 [1.35; 2.4] (p = 0.003), respectively. Selective analysis revealed a significant decrease in CFR in the anterior descending artery (1.39 [0.81; 1.57] vs. 1.75 [1.38; 1.88], p = 0.001) and circumflex artery (1.29 [0.69; 1.47] vs. 1.71 [1.1; 1.91], p = 0.013) in the PCI group.

Conclusion. Patients with previous PCI demonstrated a decrease in both MBF and CFR, indicating the development of coronary microvascular dysfunction, which is most pronounced in the left coronary artery territory. These abnormalities may impact the longterm outcomes of coronary artery bypass grafting.

Introduction. The COVID-19 pandemic has revealed the need for reliable diagnostic criteria to assess myocardial status in individuals who have recovered from the infection or undergone vaccination. The lack of standardized reference values for cardiac magnetic resonance imaging (MRI) parameters in the young population limits the accurate interpretation of detected changes.

Aim: To establish reference values for myocardial morpho-functional parameters using multiparametric cardiac magnetic resonance imaging (MRI) in young individuals who have had COVID-19 and/or were vaccinated against SARS-CoV-2.

Material and Methods. A single-center cross-sectional study included 28 volunteers (18-29 years old) without cardiac pathology. All participants underwent multiparametric cardiac MRI on a 1.5 T scanner, followed by quantitative assessment of morpho-functional parameters and myocardial deformation indices using Medis Suite software version 3.0.18.10. Preliminary, the assessment of interobserver agreement using variation coefficient and intraclass correlation coefficient (ICC) were carried out.

Results. The highest agreement was observed for global longitudinal strain (ICC = 0.91) and end-diastolic volume (ICC = 0.89), while global radial strain demonstrated the greatest variability (ICC = 0.72). Ejection fraction showed the lowest coefficient of variation (8.9%), confirming its reliability as a primary functional parameter. Reference values for cardiac MRI parameters were established for the young population with percentile interval.

Conclusion. The obtained assessment of methodological consistency provides a basis for a standardized approach to interpreting cardiac MRI data in young patients. The developed set of reference values can serve as a benchmark for identifying deviations associated with inflammatory changes, not only resulting from past COVID-19 and vaccination, but other etiological factors.

Introduction. Porous nickel-titanium (NiTi) alloys are attracting attention as implant materials due to their combination of mechanical compatibility with bone tissue and osteointegration capacity. The addition of silver nanoparticles (AgNPs) can alter the structural and phase state and surface characteristics of the material, but its biological behavior in vivo remains insufficiently studied.

Aim: To assess the biocompatibility and osseointegration potential of porous NiTiAg alloys synthesized by self-propagating hightemperature synthesis (HSS).

Material and Methods. NiTiAg alloys with 0.5 at. % AgNPs were studied by X-ray phase analysis and mechanical testing to evaluate their phase composition and properties. For the in vivo experiment, implants were placed in the cranial bone region of Balb/c mice (n = 10) for 14 days. Histological analysis was performed using hematoxylin-eosin, von Kossa staining, alizarin red S, and immunohistochemistry for osteopontin (Opn). Osteogenic differentiation of mesenchymal stem cells (MSCs) in vivo was studied on the alloy surface. The state of the immune response was assessed by the leukocyte profile.

Results. The alloys had a low modulus of elasticity and strength comparable to bone tissue. In the implantation area, preserved bone architecture, the formation of a vascularized connective tissue capsule, and the absence of an inflammatory response were observed. Staining demonstrated active mineralization and the participation of osteoblasts in the formation of new bone matrix. Opn expression indicated active osteogenesis. MSCs in vivo completely differentiated into osteoblasts with the formation of a calcium matrix. The leukocyte profile remained within physiological limits.

Discussion. The data obtained indicate that porous NiTiAg alloys are biocompatible, osteoconductive, and have low immunogenicity. The introduction of AgNPs does not have a negative effect on cells and tissues and also allows the required biocompatibility and osseointegration parameters of the material to be maintained. The material can be considered a promising basis for the creation of implants that promote bone tissue regeneration and reduce the risk of infectious complications.

The search for and practical application of immunotropic drugs capable of influencing various parts of the immune system are becoming increasingly important. Of particular interest are substances that affect the cytokine profile, which allows for correction of the immune response and ensures its adequacy in relation to the pathogen.

Aim: To study the effect of water-soluble polysaccharides extracted from blood-red hawthorn leaves on the production of cytokines by immunocompetent cells in an experiment.

Material and Methods. The study was based on cultural and enzyme immunoassay methods. The cultural methods included culturing peritoneal macrophages, splenocytes of experimental animals and mononuclear cells of the peripheral blood of healthy donors. The enzyme immunoassay methods were used to assess the content of cytokines in the conditioned media of macrophages, splenocytes from experimental animals and peripheral blood mononuclear cells from healthy donors.

Results. The polysaccharides studied change the cytokine profile, increasing the production of both pro-inflammatory and antiinflammatory cytokines by immune competent cells.

Conclusion. The data obtained allow us to consider the polysaccharides of the blood-red hawthorn as a potential basis for the creation of immunotropic drugs.

Background. One of the key components of post-ischemic damage is impaired myocardial contractility and changes in left ventricular geometry, characterized by a decrease in ejection fraction (EF), an increase in left ventricular (LV) volume, a drop in cardiac output (CO), and the appearance of areas of local contractility impairment. Limiting damage, preserving LV contractile function are the main goals of modern cardioprotection.

Aim: To assess the relationship between endogenous somatostatin (ES) and echocardiographic parameters during the experiment, as well as the effect of preventive administration of octreotide at doses of 20 and 40 μg/kg/day on systolic function indicators of the LV in an experimental model of prolonged coronary occlusion and reperfusion in rats.

Material and Methods. The study included 35 male Wistar rats divided into 3 series of experiments. Series 1 consisted of 12 intact animals (control group), series 2 consisted of 11 rats that were administered octreotide (Pharmstandard JSC) at a dose of 20 mcg/kg/ day for 8 days prior to coronary occlusion, and the third series consisted of 12 animals that received octreotide at a dose of 40 mcg/ kg/day for 8 days prior to coronary occlusion. The model included 45 minutes of occlusion of the left coronary artery and 120 minutes of reperfusion. The animals underwent thoracotomy at the level of the 2nd-3rd ribs, and a ligature was applied to the left descending coronary artery a few millimetres below its origin from the aorta. The duration of coronary occlusion was 45 min. After 45 min of ischaemia, the ligature was removed, and the restoration of blood flow was confirmed by the appearance of epicardial hyperaemia. The duration of reperfusion was 120 minutes. To assess systolic function and changes in ventricular geometry during the experiment, transthoracic echocardiography was performed at 20 and 90 minutes of reperfusion. End-systolic (ESV) and end-diastolic volumes (EDV), ejection fraction (EF), cardiac output (CO), stroke volume (SV) and local contractility impairment index (WMSI) were assessed. Levels of CK-MB (MB fraction of creatine phosphokinase) and endogenous somatostatin were determined by immunoassay (ELISA).

Results. Ischemic damage was confirmed by an increase in CK-MB in all series. In the control series, the ES level at 120 minutes of reperfusion increased statistically significantly compared to the baseline (p = 0.016), and a strong correlation was found between ES levels and EDV LV, CO, and SV indices at 90 minutes of reperfusion (r = 0.580; p = 0.048; r = 0.813; p = 0.001 and r = 0.879; p = 0.0001, respectively). The use of octreotide at a dose of 20 μg/kg contributed to an increase in EF by the 90th minute, but did not affect LVEF. The use of a dosage of 40 μg/kg/day led to a decrease in CK-MB levels (p = 0.018) and an improvement in the parameters of pump function and LV contractility.

Conclusion. ES concentration is associated with echocardiographic parameters reflecting LV contractile and pumping functions at the end of reperfusion, and the use of the somatostatin analogue octreotide dose-dependently reduces post-ischaemic left ventricular myocardial contractile dysfunction in ischaemic and reperfusion injury.

Gilles de la Tourette syndrome is the most severe form of tic hyperkinesis in children, characterized by multiple motor and vocal tics. According to world statistics, the prevalence of this disease reaches 1% in the pediatric population, and the average age of clinical manifestation of symptoms is 6-8 years. At the current stage of medical care, in accordance with international clinical guidelines, the first-line drugs of choice are atypical antipsychotics (neuroleptics) of the 2nd generation, such as aripiprazole, alimemazine, risperidone and others. Their use is justified by their high efficiency in suppressing ticks. However, despite this, standard antipsychotic therapy is ineffective in about 30% of patients, which forms a resistance group. This creates a serious clinical problem and naturally raises the question of finding alternative therapeutic strategies. In such cases, consideration of drugs from other pharmacological groups becomes an urgent direction. As demonstrated by individual clinical cases and studies, monoamine reuptake inhibitors, in particular tetrabenazine, may be a promising option. It is assumed that their effectiveness is associated with the modulation of dopaminergic transmission, which makes it possible to achieve a reduction in tic symptoms in patients who initially did not respond to traditional treatment, and opens up new ways for personalized therapy of this complex neuropsychiatric disorder.

Background. Preoperative differentional diagnosis of meningioma grade remains challenging with routine brain magnetic resonance imaging (MRI). The lack of reliable non-invasive tools limits the potential for early risk stratification and treatment planning.

Aim: To develop an interpretable classification radiomic model RadMenGR for predicting meningioma grade (Grade I or Grade II) based on contrast-enhanced T1-weighted images.

Material and Methods. This retrospective single-center study was conducted using the open-source anonymized dataset MeningiomaSEG-CLASS. 95 patients were included in the analysis (53 with Grade 1 and 42 with Grade 2 tumors). 105 radiomic features were extracted from manually segmented MR images using PyRadiomics. Classification was performed with a Naive Bayes algorithm following feature discretization using the Entropy / MDL method. Diagnostic performance was assessed using the area under the curve (AUC), sensitivity, specificity, and accuracy. Bootstrap analysis with 10,000 iterations and a 95% confidence interval was used for validation.

Results. On the validation cohort (n = 46), the ROC-AUC was 0.805 (95% CI: 0.671–0.915). The lower bound of the 95% CI for the AUC exceeded the value under the null hypothesis (AUC = 0.63), confirming the statistical significance of the results (p < 0.05). Conclusion. This study developed an interpretable radiomic classification model for the differential diagnosis of Grade 1 and Grade 2 meningiomas. The application of a Naive Bayes algorithm to features extracted from contrast-enhanced T1-weighted images and transformed using a discretization method enabled the achievement of a significant level of diagnostic accuracy. However, the width of the confidence interval points to a lack of model robustness, necessitating validation on an independent cohort.

Introduction. Differential diagnosis of non-melanocytic skin tumors remains a key challenge in dermato-oncology, as timely detection of malignant forms increases the chances of successful treatment. The subjectivity of traditional methods encourages the use of artificial intelligence (AI), but errors in computer vision programs require analysis.

Aim: To analyze the reasons of misclassification of non-melanocytic skin tumor images by AI-based programs. This was accomplished by identifying systematic differences in data characteristics and visualizing regions of interest during image recognition. The results are aimed at improving the efficiency of training and using computer vision programs.

Material and Methods. Datasets processed in the Derma Onko Check and Melanoma Check programs were used for a retrospective analysis of tumor images. For this study, malignant tumors were considered positive, while benign tumors were considered negative. Considering two types of AI decisions (true and false), four standard result classes were considered: true positive (TP), false positive (FP), true negative (TN), and false negative (FN). To visualize image quality metrics (brightness, contrast, entropy, blur, and RGB metrics), boxplots, paired scatterplots, and pixel difference maps were used. To visualize areas that significantly influence image classification, two explainable AI methods were applied: weighted class activation mapping (Score-CAM) and occlusion sensitivity. These methods allow us to understand which image regions are most important for the classification decisions of the deep neural network. To test statistical hypotheses, Welch's t-test and one-way analysis of variance were used; to assess the relationship between characteristics, Spearman's correlation analysis was used.

Results. Significant differences in image characteristics were identified. The IP results were characterized by the following features. Brightness was lower (median 0.6914 on a normalized scale of 0-1), indicating natural, uniform illumination without strong glare. Entropy was high (median 4.8584), indicating a complex texture with many clinically significant details: ulceration, irregular borders, and pigmentation variations. Blurring was moderate, providing acceptable image sharpness without severe blurring of the tumor edges and texture. The mean values of the red and green channels were balanced. The LP results had increased brightness (median 0.7994, indicating an overexposed, overly bright photo with glare, where fine textural details are lost) and low entropy (median 4.6414, indicating a uniform texture without complex patterns). Significant differences between classes were confirmed for brightness (F = 5.1848; p < 0.05), entropy (F = 5.2509; p < 0.05), FFT blur (F = 3.1136; p < 0.05), green channel mean (F = 5.3315; p < 0.05), and red channel mean (F = 3.3812; p < 0.05). The Score-CAM and Occlusion Sensitivity explainable AI methods and image quality analysis showed that non-melanocytic tumor classification errors by the Derma Onko Check and Melanoma Check AI programs occurred due to overexposure, low entropy, and photography artifacts; false positives occurred on bright, low-texture images, and false negatives occurred on dark/blurred images. AI models are distracted by the background, hair, shadows.

Conclusion. When training computer vision programs, developers are advised to perform image preprocessing (automatic white balance, gamma correction, Sobel filters for texture enhancement and Wiener filters for blur suppression, online brightness and contrast augmentation), normalize color channels, monitor key quality metrics after each training epoch, and use augmentation that compensates for the negative brightness-entropy correlation and illumination variability. Users of the programs are advised to adhere to standard shooting conditions: uniform diffuse lighting without shadows and glare, luminance < 0.75 on the normalized scale, and the absence of artifacts in the frame; shoot in macro mode from a distance of 8-15 cm, centering the tumor and ensuring entropy > 4.8 and a resolution of 2000-3000 pixels on the longest side; stabilize the camera and activate the automatic white balance function on the shooting device.