Sergey E. Khrushchev

Highlights Normothermic regional perfusion enables successful recovery of contractile function after 30 minutes of warm ischemia after circulatory death. Perfusion strategies targeting either a constant aortic root pressure (60–70 mmHg) or a constant systemic flow (100 mL/kg/min) yield comparable restoration of systolic and diastolic myocardial function, similar histological findings, and equivalent coronary sinus lactate levels. Flow‑targeted perfusion is associated with significantly higher systemic arterial pressure after weaning from cardiopulmonary bypass, suggesting more favourable early hemodynamic adaptation of the graft. Background. The shortage of donor organs remains an unresolved issue in transplantology. Donation after circulatory death is a promising avenue for expanding the donor pool but requires optimization of perfusion resuscitation protocols for grafts subjected to warm ischemia. Aim. To compare two strategies of normothermic regional perfusion – control of perfusion pressure (60–70 mmHg, group A) versus control of systemic flow (100 mL/kg/min, group B) – in an experimental DCD-donor model. Methods. The experiment was performed on 10 Landrace pigs (aged 3–5 months). Circulatory arrest was induced by exsanguination followed by 30 minutes of warm ischemia. NRP was conducted for 30 minutes, after which animals were weaned from cardiopulmonary bypass. Hemodynamic parameters, echocardiographic indices of systolic and diastolic function, coronary sinus lactate levels, myocardial edema extent, and histological changes were assessed. Results. Sinus rhythm was restored in all cases. After weaning from perfusion, group B demonstrated significantly higher systolic (107 vs. 61 mmHg, p = 0.036) and mean arterial pressure (92 vs. 71.5 mmHg, p = 0.041) compared to group A. No significant intergroup differences were found in cardiac output, echocardiographic parameters of ventricular function, lactate levels, edema extent, or myocardial histology. Conclusion. Both studied NRP strategies effectively restore heart graft function after warm ischemia. Flow-targeted perfusion is associated with higher systemic arterial pressure in the early post-reperfusion period, which may be relevant for graft hemodynamic stability.

Introduction. CABG outcomes are particularly complicated in patients withdiabetes mellitus due to diffuse coronary disease and smaller target artery diameters, increasing the risk of graft occlusion. The quality of the distal anastomosis, enhanced by microsurgical technique, may be critical for long-term results in this group. Objective. To compare the long-term outcomes of microsurgical versus standard coronary artery bypass grafting (CABG) in patients with concomitant diabetes mellitus. Methods. A retrospective analysis included 478 diabetic patients who underwent isolated CABG between 2012 and 2022. Patients were stratified into two groups: those undergoing standard CABG (OPT, n = 186) and those undergoing microsurgical CABG (MICRO, n = 292). To mitigate selection bias, 1:1 propensity score matching was performed, yielding 167 matched pairs (n = 167 per group). The primary endpoint for long-term outcomes was freedom from major adverse cardiac and cerebrovascular events (MACCE). Secondary endpoints included overall survival and the individual components of MACCE. Results. The microsurgical technique was associated with a statistically significant increase in freedom from MACCE compared to the standard technique (10-year freedom: 59.4 % vs 44.3 %, p = 0.012). Multivariate Cox regression identified duration of inotropic support (p = 0.006), female sex (p = 0.012), number of grafts (p = 0.003), and left ventricular end-diastolic volume (LVEDV; p = 0.007) as independent predictors of MACCE. No statistically significant difference in overall survival was observed between groups (10-year survival: 82.0 % vs 65.8 %; p = 0.060). Multivariate analysis identified female sex (p = 0.037) and number of grafts (p = 0.021) as independent factors influencing survival. Cardiac mortality was significantly lower in the MICRO group (p = 0.003). Independent predictors of cardiac mortality included female sex (p = 0.025), patient age (p = 0.034), and number of grafts (p = 0.026). While a trend towards improved freedom from repeat revascularization was noted in the MICRO group, the difference was not statistically significant (p = 0.17). No independent predictors for repeat revascularization were identified. The incidence of myocardial infarction was significantly reduced in the MICRO group (p < 0.001). On multivariate analysis, the microsurgical technique (p = 0.001), female sex (p = 0.011), cardiopulmonary bypass duration (p = 0.043), aortic crossclamp time (p = 0.046), inotropic support duration (p = 0.001), and number of grafts (p = 0.028) were independent factors associated with myocardial infarction risk. Conclusion. In patients with diabetes mellitus, microsurgical CABG is associated with superior long-term outcomes, evidenced by significantly greater freedom from MACCE, reduced cardiac mortality, and a lower incidence of myocardial infarction compared to the standard technique.

Introduction. Magnetic resonance imaging allows for the assessment of overall and regional myocardial contractility of the left ventricle, and the use of contrast enhancement evaluates the depth of wall damage, which together serve as important prognostic criteria for the improvement of myocardial contractile function in the postoperative period. Objective. To determine the diagnostic capabilities of magnetic resonance imaging in post-infarction cardiac aneurysms. Methods. For inclusion in the prospective observational study, 160 patients with post-infarction heart aneurysms were assessed. Preoperative modeling of the left ventricle cavity was performed on all patients. Results. Magnetic resonance imaging reliably detects a greater number of segments with impaired kinetic function compared to echocardiography. In the assessment of local contractility using delayed contrast enhancement, a higher number of segments with impaired kinetics were identified. On average, each patient had 4.40 ± 0.95 segments with abnormal kinetics. The average difference in the number of segments amounted to 68 segments [60; 87]. A negative correlation was observed between the depth of myocardial damage and the type of local contractility impairment: as the transmurality index increased, the number of segments with hypokinesis decreased (r = –0.74; p = 0.032), while the number of segments with akinesis increased (r = 0.82; p = 0.026). In terms of diagnostic performance, MRI demonstrated superior sensitivity and specificity for diagnosing postinfarction left ventricular aneurysm, with values of 97.6 % and 100 %, respectively, compared to echocardiography, which had sensitivity and specificity values of 68.5 % and 8.3 %, respectively. Conclusion. Magnetic resonance imaging reliably detects a greater number of segments with impaired kinetic function compared to echocardiography. It allows for the reliable detection of a greater number of segments with kinetic impairment compared to echocardiography. The use of MRI with delayed contrast enhancement increases the informativeness of the method. This technique is safe and does not increase hospital mortality.

Objective. To compare the immediate outcomes of microsurgical and standard techniques of coronary artery bypass grafting (CABG) in patients with diabetes mellitus (DM). Material and methods. A retrospective pseudo-randomized single-center study included 478 patients with multiple-vessel coronary artery disease (CAD) and concomitant diabetes mellitus who underwent CABG between 2012 and 2022. Patients were divided into two groups: the OPT group (n=186) — standard loupes, the MICRO group (n=292) — microsurgical technique. To reduce systematic bias and ensure group comparability, we used propensity score matching (PSM) and assigned 167 patients in each group. Intraoperative (cardiopulmonary bypass (CPB) and aortic cross-clamping time) and in-hospital outcomes (complication rate, length of hospital stay, mortality) were analyzed. Results. After PSM, both groups were comparable in clinical and demographic characteristics. Intraoperative analysis showed significantly shorter CPB (44 vs. 70 min, p<0.001) and aortic cross-clamping time (25 vs. 44 min, p<0.001) in the MICRO group. However, no significant differences were found in the incidence of postoperative complications, duration of mechanical ventilation, length of ICU-stay, hospital-stay and mortality. In the OPT group, all deaths were due to postoperative myocardial infarction, while the MICRO group was characterized by various causes of mortality. The study revealed no significant differences in rates of in-hospital major cardiovascular events and cardiac mortality. Conclusion. Microsurgical CABG in patients with DM is associated with shorter CPB and aortic cross-clamping time suggesting potential benefits of this approach. Despite no significant differences in in-hospital outcomes, a trend towards more favorable profile of fatal outcomes (with fewer myocardial infarctions) was observed in the MICRO group. Further studies are needed to investigate the impact of microsurgical techniques on long-term outcomes of CABG in patients with DM.

Background: Pulsed field ablation (PFA) is a widespread safe and effective approach to treat paroxysmal atrial fibrillation (AF). However, data regarding its use in persistent AF are limited, especially in comparison with thermal energy sources. Objective: The study aimed to assess the efficacy and safety of PFA for persistent AF treatment in comparison with radiofrequency (RFA) and cryoballoon ablations (CBA). The primary concern was to evaluate 1 year freedom from any atrial arrhythmias (AA) recurrence, including AF, atrial flutter or atrial tachycardia lasting 30 seconds or longer after the blanking period. Methods: We performed an extensive search using MEDLINE, EMBASE, and PubMed databases for studies providing outcome data on PFA in patient with persistent AF. Additionally, several studies on RFA and CBA involvement for persistent AF treatment were selected for comparative analysis. Results: Freedom from AA at 1 year after PFA, RFA and CBA was 68.95% [95 % CI 62.72%, 74.57%], 61.72% [95 % CI 51.74%, 70.79%], 68.23% [95 % CI 63.76%, 72.39%] respectively, with no significant differences between types of energy used. No significant differences were revealed in periprocedural and postprocedural complications between compared ablation types, as well. Conclusion: In patients with persistent AF, PFA required a shorter total procedural time than RFA but a longer one than CBA. Fluoroscopy time for PFA was significantly shorter than for thermal energy sources. No significant differences were found in safety or freedom from atrial arrhythmias at the 1-year follow-up between the compared ablation methods. Large randomized multicenter trials are needed to further assess the benefits of PFA compared to thermal energy sources in persistent AF treatment.

Введение: постинфарктные аневризмы левого желудочка (ПИАЛЖ) ассоциированы с высоким риском сердечной недостаточности и летальности. Роль превентивного использования внутриаортальной баллонной контрпульсации (ВАБК) у данной категории пациентов остаётся спорной. Материалы и методы: в ретроспективное одноцентровое когортное исследование включены 160 пациентов с ПИАЛЖ и фракцией выброса (ФВ) ЛЖ <40%, которым выполнены реконструкция ЛЖ и аортокоронарное шунтирование. После псевдорандомизации (propensity score matching, 1:1) сформированы две группы: с превентивным применением ВАБК (n=80) и без ВАБК (n=80). Первичная конечная точка отдаленная летальность. Результаты: применение ВАБК не оказало статистически значимого влияния на 30-дневную (ОШ=6,08; p=0,17) и отдаленную летальность (ОР=0,76; p=0,41). Независимыми предикторами отдаленной летальности явились сахарный диабет (ОР=2,65; p=0,02), хроническая ишемия нижних конечностей (ОР=2,76; p=0,038), исходный конечно-диастолический объем ЛЖ (ОР=1,01; p=0,039) и время искусственного кровообращения (ОР=1,01; p=0,029). Техника Dor ассоциировалась со снижением риска (ОР=0,35; p=0,014). Выводы: превентивное периоперационное применение ВАБК у пациентов с ПИАЛЖ и ФВ<40% не улучшает 30-дневную и отдаленную выживаемость, что поддерживает современные рекомендации по селективному использованию данного метода.

Background: Presently, the availability of single-stage surgical correction of mitral valve disease combined with atrial fibrillation (AF) via a mini-access approach remains limited. Moreover, the comparative effectiveness of this procedure versus conventional sternotomy (CS) remains poorly understood. Thus, this study aimed to conduct a comparative assessment of the efficacy and safety of concomitant mitral valve surgery and AF ablation via a minimally invasive approach (minimally invasive cardiac surgery, MICS group) versus the standard sternotomy approach (CS group). Methods: An extensive literature search was performed to identify relevant studies. Additionally, for comparative analysis, we included isolated studies where the combined intervention was conducted exclusively via either minimally invasive or CS as the primary access. Results: Freedom from atrial arrhythmia (AA) for MICS and CS was 94.52% [95% CI 91.52, 96.50] vs. 80.76% [95% CI 67.19, 89.59] and 86.22% [95% CI 80.13, 90.66] vs. 86.33% [95% CI 79.39, 91.19] at 1 and 2 years, respectively, with no statistically significant differences. Meanwhile, cardiopulmonary bypass (CPB) and aortic cross-clamp (ACC) times were significantly longer in the MICS group compared to CS (CPB: 151.50 vs. 120.01 min; ACC: 112.36 vs. 101.43 min; p < 0.001). There were no differences in mortality between groups (p = 0.709). The rate of pacemaker implantation was significantly higher in the CS group (MICS: 3.32% [95% CI 1.58, 6.87] vs. CS: 5.20% [95% CI 2.80, 9.46]; p < 0.001). Conclusion: This meta-analysis found that the minimally invasive approach was associated with longer CPB and ACC times but a lower rate of pacemaker implantation, with no significant differences observed in mortality and freedom from AA at 1 and 2 years. The PROSPERO registration: CRD42024570022, https://www.crd.york.ac.uk/PROSPERO/view/CRD42024570022.

Introduction: Pulmonary vein ostia isolation (PVI) is the main method for catheter ablation (CA) in patients with atrial fibrillation (AF) who are refractory to antiarrhythmic drug therapy (AAD). The data regarding comparison of the remote magnetic-guided navigation (RMN) and manual (MAN) radiofrequency ablation approaches for PVI in patients with AF and enlarged left atrium (LA) are limited.Objective: The study was aimed to comparison of the safety and long-term efficacy of the radiofrequency CA associated with RMN and MAN using in patients with AF and enlarged LA.Methods: The retrospective cohort included 534 patients (mean age 59.2 ± 8.7 years, 41.6% female) with different AF forms and LA >4.5 cm who underwent PVI between 2016 and 2019. The patients were divided into two groups: the RMN group (n = 267) and MAN group (n = 267). The primary safety objective was associated with preventing perisurgical complications, and the primary efficacy objective was disengagement from AF / atrial flutter (AFl) / AT (atrial tachycardia), lasting > 30 seconds, in the 3-month period after the index procedure without AAD. The comparison of the results with 1:1 propensity score matching (PSM) was applied on the basis of 11 covariates. After PSM, 235 patients were selected for each group. The entire cohort was additionally divided into the subgroups of paroxysmal AF (n = 355) and non-paroxysmal AF (n = 179) to increase efficacy assessment. After PSM, 310 and 136 patients with paroxysmal and non-paroxysmal AF were analyzed, respectively.Results: In the entire cohort after PSM (n = 470) patients were balanced completely according to AF forms. The mean values of LA diameter were 4.98 ± 0.61 cm and 4.94 ± 0.58 cm in the RMN and MAN groups, respectively. The long-term efficacy assessment was performed in 448 patients of the both groups excluding 22 (4.7%) patients due to failed contacts. The median follow-up period was 24 months (minimum 3 and maximum 72 months). In the matched cohorts, perisurgical complications were detected in 11 (4.7%) patients of the MAN group and 2 (0.9%) patients of the RMN group (Р = 0.021, OR = 5.7; 95% CI [1.22, 53.5]). The disengagement from AF/AFl/AT after 36 months of the follow up amounted to 62.6% in the RMN group and 47.9% in the MAN group (for entire follow up, P = 0.005, HR = 1.54; 95% CI [1.14, 2.08]). For paroxysmal AF subgroup (n = 310), the disengagement from AF/AFl/AT after 36 months of the follow was 67.1% in the RMN group and 60.6% in the MAN group (for entire follow up, P = 0.15, HR = 1.34; 95% CI [0.90, 1.98]). In the non-paroxysmal AF subgroup (n = 136), the disengagement from AF/AFl/AT after 36 months of the follow up was higher in the RMN group as compared to the MAN group (59.6% and 30.4%, respectively, for entire follow up, P = 0.005, HR = 2.01; 95% CI [1.23, 3.29]) predominantly due to persistent AF.Conclusion: The present propensity-score matching study evidentiated that RMN CA was superior over manual CA for the interventional treatment of patients with AF and enlarged LA with respect to perisurgical complications and long-term disengagement from AF/AFl/AT predominantly due to non-paroxysmal AF. Prospective randomized studies are recommended for the comparison of the outcomes related to RMN and manual CA in patients with AF and enraged LA. Received 24 April 2024. Accepted 8 May 2024. Funding: Work by P.S. Ruzankin and S.E. Khrushchev was carried out within the framework of the state assignment of the Sobolev Institute of Mathematics of the Siberian Branch of the Russian Academy of Sciences, project FWNF-2024-0001. Conflict of interest: The authors declare no conflict of interest. Contribution of the authorsConception and study design: A.B. Romanov, V.V. Beloborodov, V.V. Shabanov, A.G. FilippenkoData collection and analysis: V.V. Beloborodov, A.B. Romanov, D.A. Elesin, V.A. Boboshko, V.V. Shabanov, A.G. Filippenko Statistical analysis: P.S. Ruzankin, S.Ye. Khrushchev, A.B. RomanovDrafting the article: A.B. Romanov, V.V. Beloborodov, P.S. Ruzankin, S.Ye. KhrushchevCritical revision of the article: A.B. Romanov, V.V. Beloborodov, P.S. Ruzankin, S.Ye. KhrushchevFinal approval of the version to be published: A.B. Romanov, V.V. Beloborodov, V.V. Shabanov, A.G. Filippenko, D.A. Elesin, V.A. Boboshko, S.Ye. Khrushchev, P.S. Ruzankin

Aim. To compare the long-term outcomes of the catheter ablation (CA) using remote magnetic-guided navigation (RMN) and manual radiofrequency CA (MAN) in patients with congenital heart defect (CHD) and incisional atrial tach-yarrhythmias (AT).Methods. In this retrospective study cohort, 67 patients were included with CHD and AT. CHD were classified based on complexity (simple, moderate, and complex) according to ACC/AHA guidelines 2008. Fifty-seven (85%) patients underwent at least one surgical procedure for CHD correction before CA. The patients were divided into the two groups regarding CA approach: the MAN group (n=42) and the RMN group (n=25). The primary endpoitnts was long-term freedom from any AT, including atrial fibrillation. Key secondary endpoints included perioperative and late complications. To compare freedom from any AT between the groups, 1:3 propensity score matching was applied, and 63 patients were matched. The matching was exact on CHD complexity. The weighted matched observations were assessed with univariate Cox regression with any AT as the outcome.Results. The median follow-up period was 20 months. In the matched MAN and RMN groups, 92.3% and 83.3% patients, respectively, had incisional АТ (p=0.27), the other patients having additionally AF. The mean fluoroscopy time was statistically significant lower in the RMN group compared with MAN (р=0.009) with longer procedural duration in the RMN group (pConclusion. RMN CA was superior over manual CA with respect to long-term freedom from AT in patients with CHD with similar safety profile.