Sergei S. Durmanov

Aim. to evaluate the results of pulmonary vein isolation (PVI) and spatio-temporal dispersion (STD) radiofrequency ablation (RFA) and the recurrence rate of atrial fibrillation (AF) in patients with non-paroxysmal AF after intraoperative intravenous administration of novocainamide. Methods. The study included 67 patients with persistent and long-standing persistent AF who underwent the primary RFA PVI and STD procedure. Stages of the operation: coronary sinus catheterization, interatrial septum puncture twice, PVI, administration of novocainamide in the right atrium, mapping and RFA of STD zones in the left atrium, ifnecessary, in the right atrium and in the coronary sinus. The final goal of RFA was conversion to sinus rhythm (SR) or transformation into atrial flutter (AFl)/regular atrial tachycardia (AT) with subsequent mapping and RFA. If AF/AFl/AT persisted, an electrical cardioversion (ECV) was performed. Then, PVI and linear blocks were evaluated/restored. An electrocardiogram and Holter monitoring were recorded at 3 and 6 months later to analyze the effectiveness. Results. PVI was achieved in each case. Acute conversion of AF to SR occurred in 7 patients (10.4%), in sustained AFl/AT in 26 (38.8%). In 18 of 26 patients (69.2%), AFl/AT were ablated with SR restoration. 42 patients (62.7%) required ECV. After 3 months, there was no recurrence of AF in 40 patients (88.9%), AF/AFl/AT in 31 (68.9%), 6 months later in 32 (80%) and 24 (60%) respectively. There were no differences in freedom from AF/AFl/AT 6 months later between the AF and ECV group at the end of the procedure and the SR/AFl/AT group (log-rank=0.333), while the latter had significantly fewer AF recurrences (log-rank=0.004). In patients who converted to SR/AFl/AT during RFA, the probability of AF recurrence during the 6-month follow-up period was 10 times lower than in patients with persistent AF and ECV (OR 10.4 (95% CI 1.351-81.120), p=0.025. Conclusion. In 49.3% of cases, AF was stopped during RFA PVI and STD. The probability of AF recurrence in this case was 10 times lower than in the case of persistent AF and ECV at the end of the operation. There were no differences in the absence of AF/AFl/AT recurrence between patients with intraoperative conversion to SR/AFl/AT and persistent AF.

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.

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.

Aim. The aim of the study was to study the effect of first appeared persistent left bundle branch block on the prognosis of patients after «MedLab-CT» transcatheter aortic valve implantation (TAVI) in the middle long-term follow-up period. Methods. The study included 129 patients after the TAVI procedure, who initially did not have LBBB. The average age of patients was 70.2±5.2 years, body mass index - 31.4±5.9 kg/m2, the proportion of men was 36%, arterial hypertension was diagnosed in 93%, diabetes mellitus in 32%, coronary heart disease in 59% of patients, paroxysmal form of atrial fibrillation was registered in 16%, permanent form of atrial fibrillation - in 3% of patients. According to echocardiography the end-diastolic volume was 107.7±30.9 ml, the ejection fraction was 61.4±10.4%, the maximum and average pressure gradient on the aortic valve was 91.7±25.7 mmHg and 52.7±16.4 mmHg respectively. The width of the QRS complex was 84.1±12ms. Depending on the occurrence of LBBB after the TAVI procedure, the patients were divided into 2 groups: the first group included 98 patients without LBBB (the width of the QRS complex was 98.4±16ms), the second included 31 patients with LBBB (the width of the QRS complex was 149.6±17ms). The groups were comparable in other clinical, demographic and ultrasound parameters. The follow-up period was 60 months. Results. There were no differences in echocardiography data in both groups, and mortality rates from all causes were also comparable. During the follow-up period in the LBBB group two patients was implanted a pacemaker (6.45%; p=0.001). The LBBB after TAVI did not increase all-cause mortality in patients (OR 1.084; DI= 0.353-3.209; p=0.912). Conclusion. The first time arisen LBBB does not increase mortality in patients after TAVI «MedLab-CT» in the middle long-term follow-up period, but it is associated with a higher risk of developing a high-grade atrioventricular block requiring pacemaker implantation.

Aim. To evaluate the prognostic value of local captures after pulmonary vein isolation in patients with nonparoxysmal atrial fibrillation (AF) for the long-term results of radiofrequency ablation (RFA).Methods. A single-center observational prospective study. The total number of patients 110. All patients underwent primary catheter ablation for nonparoxysmal AF. During the operation, the activity of pulmonary veins and the presence of local captures were assessed. Patients with local captures in at least one pulmonary vein were included in the first group. Patients who had no local captures were included in the second group. The number of patients in the first group is 54 patients, the number of patients in the second group is 56 patients. The groups had no statistically significant differences in the main indicators -gender, weight, age, duration of medical history, volume of the left atrium and left ventricular ejection fraction, as well as in concomitant pathology. The time of RFA and fluoroscopy, and the duration of operations between the groups also had no statistically significant differences.Results. The follow-up period was 800 [286.5;800] days. The overall effectiveness of the treatment was 68.2% (75 patients out of 110), considering repeated operations. In the group with local captures, sinus rhythm was maintained at the end of the follow-up period in 42 out of 54 patients (77,7%), in the group without local captures in 33 out of 56 patients (58,9%). The difference is statistically significant (odds ratio 2,439 (95% confidence interval 1,060 -5,615 p=0,034). The presence of local captures in the construction of a multifactorial logistic regression model is a predictor of the effectiveness of RFA (χ2=14,710; p=0,012).Conclusion. In this study, local captures in the pulmonary veins in patients with nonparoxysmal atrial fibrillation were a predictor of improved long-term results of radiofrequency ablation.

Aim. To evaluate the clinical outcomes of persistent arteriovenous fistulas (AVF) after catheter ablation (CA) of atrial fibrillation (AF), to determine potential predictors and the likelihood of self-resolution while taking anticoagulants.Methods. Thirty-six patients with AVF after CA AF (14 men, age 59.9±8.4 years) were included. Pulmonary veins were isolated for everyone. Femoral vein catheterization was performed according to anatomical guidelines. Hemostasis was performed with a “figure of eight” type suture, a pouch suture or a compression bandage. With symptoms suggesting the presence of vascular access complications (VAC), ultrasound duplex scanning (UDS) was performed the next day after the CT. When AVF was detected, compression bandages were treated. While maintaining AVF, outpatient follow-up continued, including UDS, echocardiography, and questionnaires. Surgical treatment was performed with a combination of AVF with other VAC, with paired AVF, and with refusal of observation.Results. The incidence of AVF was 1.19%. Compression therapy was effective in 8 (22.2%) patients, surgical treatment was performed in 7 (19.4%). In no case was AVF symptomatic, and there were no indications for immediate surgical treatment. Outpatient follow-up was continued 14. The duration of follow-up was 24 [12; 28] months. In 8 patients, AVF resolved on its own, in 1 previously closed AVF relapsed. Minor local symptoms were noted in 4 out of 7 patients with persistent AVF. In 15 (41.7%) of 36 patients, AVF resolved independently or with the help of compression therapy. The only independent predictor of self-closure of AVF in a single-factor logistic regression analysis was the age of patients (odds ratio (OR) 0.807; confidence interval (CI) 95% 0.651-1,000; p=0.050). Using ROC analysis, it was shown that the age over 65.5 years reduced the chance of self-closure of AVF by 93.7% (OR 0.067; CI 95% 0.007-0.614; p=0.017).Conclusion. The frequency of spontaneous closure of AVF after AF was 57.1%. The only independent predictor of AVF persistence was the patient’s age over 65.5 years. None of the patients with persistent AVF developed symptoms of heart failure and vascular symptoms that required immediate surgical closure.

Aim. To assess factors influencing the degree of tricuspid regurgitation (TR) and the function of the right heart chambers in patients with two endocardial right ventricular leads of a permanent pacemaker.Methods. A retrospective analysis of 5807 electronic medical records of patients who underwent primary implantation or planned replacement of a permanent pacemaker was performed. In 119 cases, a new right ventricular lead was additionally implanted, of which a group of 27 patients was selected according to the selection criteria. A control group of 129 patients was formed. Pseudo-randomization was performed, 27 comparable pairs were formed. To determine the predictors of TR progression, the logistic regression method for a multivariate model was used.Results. In the late postoperative period, echocardiographic indices of both groups were virtually identical and were within the age norms. In the control group, minor TR was detected in 62.9% (n=17) of patients, moderate indices were diagnosed in 29.7% (n=8) of cases, and no TR was detected in 7,4% (n=2), respectively. In the observation group, minor TR was diagnosed in 74,1% of cases (n=20), moderate indices of insufficiency were diagnosed in 18.5% (n=5), severe TR was recorded in 3,7% (n=1) of patients, and TR was not detected in the same number of patients. Multivariate logistic regression identified the only independent predictor of TR progression in the postoperative period - the presence of non-paroxysmal atrial fibrillation (AF), which increases the probability of progression of the degree of tricuspid valve insufficiency in the remote observation period by 3/8 times. The relationship between the fact of the presence of two electrodes in the right ventricular cavity and the increase in the degree of tricuspid valve insufficiency was not determined.Conclusion. In patients with two right ventricular leads, TR and right heart function don’t change significantly in the long-term observation period. The leading factor influencing TR progression is the history of non-paroxysmal AF.

Aim. To study the change in the position of the esophagus during radiofrequency ablation of the pulmonary veins (RFA PV) using esophagographyMethods. The period of the study is from August 2022 to January 2023 inclusive. The study is a single-center observational non-randomized study. The study included 191 patients. RFA PV were performed under conscious sedation with dexmedetomidine and fentanyl. The patients were available for verbal contact throughout the operation. After performing a transeptal puncture, esophagography was performed in the LAO 30° projection using 10 ml of Omnipac water-soluble contrast agent (GE Healthcare Ireland). At the end of the operation, esophagography was performed repeatedly. The position of the esophagus was determined relative to the shadow of the spine. Measurements were carried out at three levels: the upper one at the intersection of the esophagus and the roof of the left atrium, the lower one at the intersection with the ring of the mitral valve; the middle level at the middle of the distance between the upper and lower measurements. The width of the contrasted lumen of the esophagus was measured at the same levels. Lateral displacement of the esophagus was defined as the difference in the values of measurements of the position of the lateral and medial boundaries of the esophageal shadow on esophagograms obtained at the beginning and end of the operation.Results. The average lateral displacement of the esophagus was 2.0 ±1.9 mm at the upper level, 3.4±1.6 mm at the middle level and 1.4±1.2 mm at the lower level of the left atrium. There was no significant statistically difference in the change in the position of the esophagus at the beginning and end of the operation (p=0.251, p=0.558, p=0.824, respectively, for the upper, middle and lower measurement levels). The most significant displacement of the esophageal shadow was 5.3 mm. The maximum change in the width of the contrasted lumen of the esophagus was 5.5 mm.Conclusions. According to esophagography with water-soluble contrast, the position of the esophagus during RFA PV does not experience clinically significant changes.

Aim. To examine the impact of late gadolinium enhancement (LGE) in the left ventricular myocardium on magnetic resonance imaging (MRI) on overall mortality and the phases of arrhythmic events in patients with ischemic cardiomyopathy and implantable cardioverter defibrillator (ICD).Methods. This was a single-center retrospective study. A total of 382 medical records of patients from the period between 2019 and 2022, who underwent ICD implantation as part of primary prevention of sudden cardiac death at National Centre of Cardiovascular Surgery, were analyzed. Seventy-four patients were selected for the study. Observation was conducted through in-person examinations and remote monitoring. Endpoints evaluated included overall mortality and arrhythmic events. The cause of death was determined based on the “Promed” medical database. Patients who reached a specific endpoint constituted the case group, while those who did not reach any endpoint formed the control group.Results. During the observation period, arrhythmic events were registered in 26 patients (35.1%), with a total of 27.1±13.2 events. Twenty-one patients (28.4%) deceased. In univariate regression analysis, the presence of LGE, the extent of LGE (%), and the number of segments with LGE served as predictors of ICD activation and overall mortality. Two multivariate logistic regression models were constructed. ROC curves were used to determine the quality of the regression model, with an area under the curve of 0.807 for ICD activation and 0.789 for mortality. The highest sensitivity and specificity of the method were observed with a LGE value equal to or greater than 14% for ICD activation (sensitivity 81%, specificity 75%) and 26% for overall mortality (sensitivity 89%, specificity 64%).Conclusion. Substantiated ICD activations (shock/antitachycardia pacing) were observed in 35.1% of cases, and the overall mortality rate was 28.4%. The association between ICD activation and the extent of LGE occurred when LGE was >14%. The association between overall mortality and the extent of LGE occurred when LGE was >26%.

Aim. To study how the presence of local capture (LC) after pulmonary vein (PV) isolation affects the effectiveness of radiofrequency ablation (RFA) in patients with paroxysmal atrial fibrillation (AF)Methods. The study was a single-center, observational, prospective study. The total number of 186 patients. All patients underwent RFA PV for paroxysmal AF. During the operation, the activity of PV and the presence of LC were assessed. Patients in whom LC after PV isolation occurred in at least one PV were included in the first group; patients in whom LC were absent - in the second group. The first group - 98 patients, the second group - 88. Patients in the groups did not statistically differ in the main indicators - weight, gender, age, duration of anamnesis, left atrium volume and ejection fraction, as well as in the presence of concomitant pathology. The duration of the operation, the time of RFA and time fluoroscopy between the groups also did not differ statistically.Results. Mean observation time for patients was 374.4±25,.2 days. In the first group, sinus rhythm was maintained in 82 patients out of 98 (83,7%), in the second group 60 patients out of 88 (68.2%). The difference is statistically significant odds ratio 2.392 (95% confidence interval 1.189 - 4.816, p=0.031).Conclusion. The presence of local captures of the myocardium of the pulmonary veins after radiofrequency isolation is associated with an improvement in the results of treatment of patients with paroxysmal AF.