Aim. To study the characteristics of the atrial fibrillation (AF) cryoballoon ablation (CBA) procedure and features of patient’s management in real clinical practice in Russia.

Methods. “Prospective Atrial Fibrillation Cryoablation Registry” is an observational prospective national multicenter study. It was conducted from 01.2017 to 12.2019 in centers of Russian Federation. The registry included patients over the age of 18 who were agreed to participate this study and had indications for CBA of AF. The study protocol did not provide for significant restrictions on inclusion criteria, procedure technique and postoperative follow-up. The data was collected prior to the CBA of AF, during hospitalization for CBA and on the 12-month follow-up.

Results. Participating centers enroll 980 patients according to inclusion criteria. CBA of AF was performed in 976 (99.6%) (mean age 59.7±9.2 years, 545 (55.8%) men) primary procedure - 840 (86.1%), re-ablation - 136 (13.9%). Parox- ysmal AF occurred in 828 (84.8%) patients and persistent AF (mean time of persistence 4.4±3.7 months) - in 145 (15.1%) patients. The average procedure time was 108.1±33.3 minutes and mean fluoroscopy time was 24.9±13.6 min. Most of the procedures were performed under general anesthesia. Complications after AF CBA occurred in 53 (5.4%) patients. The most common complication was paresis of the phrenic nerve - 20 (37.7%) cases which were associated with lower temperatures of CBA application of the right pulmonary veins (τ=0.08; p<0.05). The features of antiarrhythmic and anticoagulant therapy were evaluated. A group of patients without adequate anticoagulant therapy in the postoperative period was identified. Due to COVID-19 restrictions only 374 (38.3%) patients completed 12-month follow-up. The recurrence of arrhythmia was occurred in 85 (22.7%) patients. Multivariate regression analysis revealed the following predictors of arrhythmia recurrence: the first procedure (OR 3.96; p=0.023), male sex (OR 1.77; p=0.014), duration of the procedure (min) (OR 1.01; p=0.007).

Conclusion. CBA is an effective and relatively safe procedure for the treatment of paroxysmal and persistent AF. Data from real clinical practice show a low proportion of serious complications of AF CBA. Data on the dynamics of drug therapy, including anticoagulant and antiarrhythmic therapy, were obtained. The attention of specialists performing AF catheter ablation and patient monitoring is required, since errors in patient management have been identified.

Aim. Comparative evaluation of short-term and long-term outcomes of radiofrequency pulmonary vein isolation using the “Ablation Index” module versus without in patients with paroxysmal and persistent forms of atrial fibrillation.

Methods. The study included 286 patients with paroxysmal and persistent forms of atrial fibrillation, divided into 2 groups: the study group (110 patients) underwent radiofrequency pulmonary vein isolation using the “Ablation Index” module, while the control group (176 patients) underwent isolation without the use of the “Ablation Index” module.

Results. The average follow-up period was 38.1±9.6 months. There was no significant difference in freedom from atrial tachyarrhythmias in the long-term follow-up between the study and control groups (58.1% vs. 62.3%, p=0.667), or in the number of perioperative complications (3.6% vs. 8.5%, p=0.106). A significant reduction in the duration of the procedure was observed when using the “Ablation Index” module (92.7±20.9 min vs. 126.4±29.2 min, p<0.001), as well as in the recurrence rate of atrial fibrillation in the blanking period (1.8% vs. 8.5%, p=0.020).

Conclusion. Interventional treatment of atrial fibrillation under the control of the “Ablation Index” module shows significantly lower recurrence rates of atrial tachyarrhythmias in the blanking period and comparable safety and long-term efficacy results compared to interventional treatment using catheters with contact force sensor over a period of more than three years.

Aim. To study the dynamics of left atrial appendage (LAA) thrombosis and to determine the factors associated with resistant LAA thrombus in patients with non-valvular atrial fibrillation (AF) during 12 months of follow-up.

Methods. A prospective study included 83 patients with LAA thrombosis detected by transesophageal echocardiography (TEE). The end point was resolution or stability of the thrombus. All patients underwent clinical examination, complete blood count and biochemical blood test, coagulation testing, transthoracic echocardiography (TTE) and TEE.

Results. According to the results of TEE, the patients were divided into two groups: group 1 (n=45) with resolution LAA thrombus and group 2 (n=38) with resistant LAA thrombus. Group 2 patients were more likely to take beta-adrenoblockers (57.9% and 31.1%, p=0.014), diuretics (60.5% and 35.6%, p=0.023) and rivaroxaban (39,5% и 13,3%, р=0,010). According to TTE data, group 2 had a higher right atrial volume index (30.7 [24.7; 34.7] vs 24.5 [21.0; 32.2] ml/m², respectively, p=0.034). Laboratory data analysis showed that group 2 had higher mean platelet volume (MPV) levels (9.1 [8.3; 9.8] vs 8.4 [7.9; 9.4] fl, p=0.035), platelet distribution width (PDW) (15.9 [15.7; 16.2] vs 15.7[15.5; 15.9] %, p=0.007) and platelet large cell ratio (P-LCR) (30.0±9.2 vs 25.3±7.4%, p=0.014).

There were significant direct correlations of MPV and P-LCR with the following parameters: right atrial volume, left atrial volumes, pulmonary artery systolic pressure, red blood cell level, hemoglobin level and hematocrit. The inverse association of MPV and P-LCR was with platelet count.

Conclusions. Resistance of LAA thrombus to resolution in patients with non-valvular AF is associated with morphofunctional parameters of platelets, which correlate with atrial structural remodeling. The results obtained indicate the need to continue research aimed at studying the contribution of the platelet activity to resistance to LAA thrombus, despite taking oral antocoagulants.

Aim. To evaluate the effect of mitral valve (MV) reconstruction using rigid and superelastic support rings for up to one year in patients with mitral regurgitation (MR) II according to A. Carpentier on the development of atrial fibrillation (AF).

Methods. The study included 62 patients with indications for surgical correction of MR and sinus rhythm (SR): group I (n=31) - with implantation of the biological semi-rigid saddle closed ring NeoRing and II (n=31) - with implantation of the rigid open ring RIGID. The average age of patients was 56.6±11.2 years and 58.0±10.2 years in groups I and II. Both groups were comparable in gender (men - 67.7% and 61.3%), age, comorbidity, functional class of chronic heart failure according to NYHA. The rhythm in patients was assessed by Holter monitoring at control points after 9 days and 12 months.

Results. The duration of artificial circulation, aortic occlusion, and the incidence of isolated P2-segment prolapse did not differ in the comparison groups. A positive effect on the reverse remodeling of the left heart was revealed: the end-diastolic dimension of the left ventricle (p<0.001), the left atrium (p<0.001), a decrease in the overload of the pulmonary circulation and a decrease in pressure in the pulmonary artery (p<0.001). According to the Holter monitoring data, all patients had SR. Both groups showed a satisfactory result at the hospital stage in the form of restoration of the locking function of the MV (p<0.001) and a low frequency of the revealed maximum MR up to grade 1 in group I - 9.7% and II - 29% (p=0.292). However, patients with RIGID had higher values of transvalvular diastolic gradient on MV and transvalvular flow velocity (p < 0.001). In group II, the values of transvalvular diastolic gradient on MV were Pcp 3.34±1.01 mm Hg, versus 2.39±0.62 mm Hg in group I (p < 0.001), transvalvular flow velocity in group II was Vcp 79±15 cm/sec versus 66±12 cm/sec in group I, respectively (p < 0.001). After 12 months, the RIGID group more often showed a change from SR to AF - 11 cases (35.5%), in NeoRing - 4 (12.9%). According to echocardiography data after 12 months, freedom from MR ≥ grade 2 in group I was 93.5%, versus 77.4% in group II (p=0.076). In addition, patients in group II maintained higher values of transvalvular diastolic gradient on MV - Pcp 3.70 [3.00; 4.40] mmHg, versus 2.3 [2.05; 2.85] mmHg (p<0.001), as well as higher transvalvular flow velocity - Vcp 79 [71; 94] cm/sec versus 70 [64; 79] cm/sec (p=0.017). AF developed 12 months after surgery in those patients whose transvalvular diastolic gradient on the MV exceeded 2.7 mm Hg, as well as in patients with developed MR ≥ grade.

Conclusions. The development in the medium term, after reconstruction of the mitral valve with a support ring, of an increased transmitral diastolic gradient and MR ≥ grade 2 is the cause of the development of AF, while the implantation of a rigid ring is accompanied by a high risk of developing AF within 12 months after surgery (p=0.029).

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 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 study the impact and safety of cryoballoon ablation of the pulmonary vein (PV), supplemented by isolation of the superior vena cava in patients with persistent atrial fibrillation (AF).

Methods. The study is single-center, randomized, prospective. The total number of patients was 40. All of them underwent cryoballoon isolation of the PV for persistent AF. The patients were then divided into two groups: the first group included patients who underwent the standard procedure, and the second group included patients with the standard procedure supplemented by isolation of the superior vena cava. Patients in both groups had similar anatomical and clinical-anamnestic parameters. The duration of the surgical intervention was not statistically different.

Results. The average follow-up period was 354±19 days. In the group of classical cryoballoon PV isolation, after 12 months of observation without antiarrhythmic therapy, sinus rhythm was maintained in 40% of patients (8 people), in the group of extended cryoballoon PV isolation - in the same number of patients (40%, P=1). In the PV isolation group, persistent phrenic nerve palsy was observed in no patients, and in the extended ablation group, in eight patients (40%, P=0.0016). At the end of the observation, no remote complications were registered.

Conclusions. In patients with persistent AF, cryoballoon PV isolation supplemented by superior vena cava isolation is a less safe technique than standard cryoballoon pulmonary vein isolation, with comparable efficacy.

The aim of the study was to evaluate the effect the impact of the coupling interval (CI) of ventricular ectopic beats (VEB) on their hemodynamic properties.

Methods. The hemodynamic properties of VEBs were studied using the example of ventricular parasystoles with typical manifestations. The hemodynamic properties of VEB were studied using the example of ventricular parasystoles with typical manifestations (significant differences in CI, “multiplicity,” presence of “fusion” QRS complexes) in two female patients without structural heart abnormalities, each having more than 10000 monomorphic VEB per day. The research method involved measuring blood pressure (BP) with each heartbeat. The duration of the study, over the course of which systolic BP (SBP), diastolic BP (DBP), and pulse BP (PBP) were recorded, was 15 minutes.

Results. The hemodynamic properties of VEB were determined by assessing the correlation between the duration of the CI and the SBP, DBP, and PBP of the VEB. The SBP, DBP, and PBP values showed a highly significant correlation with the CI of the VEB: the shorter the CI, the lower the SBP and PBP, and the higher the DBP. The DBP was more strongly dependent on the CI than the SBP, and the PBP was even more dependent. The relationship between the DBP and CI of the VEB was linear, whereas the relationship between the SBP and PBP with the CI of the VEB was nonlinear: it was more pronounced with short (decreased BP) and long CIs (increased BP). There was also a highly significant correlation between the PBP and SBP of the VEB, as well as between the PBP and DBP of the VEB: the PBP of the VEB was influenced by both the decrease in SBP and the increase in DBP, but more so by the decrease in SBP.

Conclusions. As the CI of VEB shortens, its SBP decreases and DBP increases. The relationship between DBP and CI is linear, whereas the relationships between SBP and PBP with CI are nonlinear: they are more pronounced with short (decreased BP) and long (increased BP) CIs. The PBP of VEB depends on both the decrease in SBP and the increase in DBP, but it is more strongly associated with SBP.

We describe suppression of frequent premature ventricular contractions from the papillary muscle by flecainide in a patient with a history of reversible cardiomyopathy associated with arrhythmia and ineffective antiarrhythmic therapy with other IC and III class drugs, as well as refractory to repeated catheter ablation.

Supraventricular premature beats (PACs) are common in the general population. Previously considered a benign ECG finding with little clinical significance. However, increasing evidence now suggests a positive correlation between the frequency of PACs and the risk of developing atrial fibrillation, ischemic stroke, transient ischemic attack, and all-cause mortality. This has highlighted the importance of determining the clinical significance of PACs and the management strategies for affected patients.

The results of recording the same electrocardiogram by different devices are compared, the role of filtration in displaying fragmented QRS complexes is discussed.