Aim. To analyze myocardial work in cardiac resynchronization therapy (CRT) and to determine the factors influence its positive dynamics. Materials and methods. Global longitudinal strain (GLS) and myocardial work parameters including global constructive work (GCW), global wasted work (GWW), global work index (GWI) and global work efficiency (GWE) were analyzed in addition to standard transthoracic echocardiography (TTE) in 60 patients (mean age 61±10 years, 36 male) with left bundle branch block (LBBB), chronic heart failure (HF 2 [2; 3] FC (NYHA), decreased left ventricular ejection fraction (LF EF=28 [23; 31] %) before and 6 months after CRT implantation.. In all patients the segments with maximum and minimum WI value were determined and the difference in segments with maximal and minimal WI (Max-Min WI), as the indicator of myocardial work asymmetry was calculated. Results. CRT led to reverse cardiac remodeling in 44 (73.3%) patients; clinical stabilization without positive TTE dynamics – in 11 (18.3%) patients, worsening or death – in 5 (8.3%) patients. In both groups of reverse remodeling and clinical stabilization CRT resulted in GWW reduction and thus GWE and GWI enhancement. However, the decrease in GWW in these patients is not accompanied by an increase in GCW and GLS, in contrast to patients with reverse remodeling, who developed statistically significant change in GCW and GLS during CRT. Patients with worsening or death were characterized by a minimal decrease in GWW in CRT (62,0 [9,7; 133,7] vs 149,5 [92.8; 206,2] mmHg% in patients with reverse remodeling and clinical stabilization; p=0,035). Max-Min WI turned out to be directly related to the LV EF change in CRT (rxy=0,336; p=0,017) that makes this value to be one of possible predictors of reverse remodeling during CRT. Conclusion. Wasted myocardial work can serve a contractile reserve, which represent a target for CRT. Its mobilization and decrease can lead to stable clinical status in patients even in the absence of reverse myocardial remodeling.

A new dosage form of lappaconitine hydrobromide has been created – the long-acting drug Allaforte®, which has fewer side effects compared to the traditional dosage form (Allapinin®). Objective. To evaluate the effectiveness, safety and tolerability of Allaforte® therapy in comparison with the drug Rytmonorm® in patients with paroxysmal atrial fibrillation (AF). Material and methods. Patients who met the inclusion criteria and those who did not meet the non-inclusion criteria were randomized into 2 groups: 1st (n=50) – patients received Allaforte® 25 mg 3 times a day with an increase in dose to 50 mg 2 times a day when detected attack of AF; 2nd (n=50) – patients received Rytmonorm® 150 mg 3 times a day with an increase in dose to 300 mg 2 times a day if an attack of AF was detected. Results. The average time from the first dose of the drug to the development of AF paroxysm in the 1st group (Allaforte®) was 98.877±6.022 days, in the 2nd group (Rytmonorm®) – 98.808±5.876 days, the average time from the first dose of the drug to the completion of the study – 105.740±5.032 and 103.732±5.353 days, respectively. The drugs Allaforte® and Rytmonorm® equally improved the quality of life of patients. A comparative analysis in groups according to the severity of adverse events and their cause-and-effect relationship with the drug did not show significant differences. Conclusion. The study drugs showed comparable effectiveness in preventing attacks of AF with similar safety and tolerability.

Atrial fibrillation (AFib) and chronic heart failure (CHF) are frequently encountered cardiovascular conditions that share common causes and tend to coexist in some patients. Such coexistence represents a major issue due to augmentation of symptoms severity, rapid deterioration, and poor prognosis. Management of patients with AFib and CHF is challenging due to limitations in pharmacotherapy and decreased efficacy of cardiac interventions. In this review we focus on crucial pathogenic components of AFib and CHF coexistence, key treatment approaches and discuss potential for implementation of artificial intelligence.

Aim. To compare efficacy and safety of refralon and amiodarone for cardioversion in patients with paroxysmal atrial fibrillation and flutter (AF/AFL). Methods. The study included 60 patients (32 men and 28 women) with symptomatic paroxysmal AF/AFL. All patients underwent a preliminary examination to exclude contraindications to cardioversion. The procedure of pharmacological cardioversion was carried out in the intensive care unit. By the method of envelope randomization, patients were divided into equal groups of refralon and amiodarone, 30 participants each. Both groups did not differ significantly in terms of main clinical characteristics. Cardioversion with refralon consisted of four subsequent iv injections: 5-5 - 10-10 µg/kg of body weight at intervals of 15 minutes. Patients of the second group were intravenously administered amiodarone at a dose of 5 mg/kg of body weight for 20-60 minutes, depending on the tolerability of the drug. In case of AF/AFL maintaining after 60 minutes from the start of administration, the infusion of amiodarone 100 mg/h continued until restoration of sinus rhythm (SR) or until the maximal total dose of 1200 mg/day was reached. Patients were observed for 24 hours.Results. SR restored in 96.7% (29 of 30) of patients in the refralon group, of which 56.7% (17 of 30) - after a dose of 5 μg / kg. In the amiodarone group SR restored in 53.3% (16 of 30) patients (p<0.001). Median time to arrhythmia conversion in refralon group was 14 [7;23] min, while in amiodarone group it was 150 [82;240] min (p<0.001). Within 60 minutes SR was restored in 26 patients in group of refralon and only in 4 patients in group of amiodarone (p<0.001). There were no statistically significant differences in the incidence of major adverse cardiac events, bradyarrhythmias, lowering of blood pressure, and QT prolongation between the groups.Conclusion. In randomized trial Refralon demonstrated higher rate of successful AF/AFL conversion and shorter time to SR restoration than amiodarone. The most of patients restored SR after administration of the lowest dose of refralon, that ensures the safety of cardioversion.

Aim. To evaluate the survival and dynamics of clinical and instrumental data in patients with chronic heart failure (CHF), atrial fibrillation (AF) and cardiac contractility modulation (CCM). Methods. There were included 54 patients (40 men, median age 59.7 [56.6; 63.9] years) with signs of CHF II (n=27, 50%) functional class and III (n=27, 50%) NYHA functional class, significantly decreased left ventricular ejection fraction (LVEF=30 [24,7; 35,5]%), LV dilatation and paroxysmal (n=27, 50%) or permanent (n=27, 50%) AF. In all patients, devices for CCM were implanted. The dynamics of clinical and instrumental parameters were assessed in 2, 6, 12 and 24 months after implantation. The actual survival patients with CCM was compared with the predicted survival calculated using the Seattle model of heart failure and MAGGIC risk score. Results. In 14 (28%) of patients CCM resulted in significantly increased clinical, echocardiographic parameters (increase in LVEF by 15 [11; 20]%, decrease in end-systolic volume by 68,5[37.5;104.5] ml and end-diastolic volume by 44 [30,100] мл), increase in walking distance during 6-minute walking test and decrease of NT-proBNP. The only factor significant for maximal response was non-ischemic etiology of CHF (χ 2 =4.54, p=0.034). During 2 years 21 (42%) patients died. The all-cause mortality in patients with CCM to the first year of observation was 16%, two-year all-cause mortality - 40%. These figures turned out to be significantly higher than predicted according to the Seattle model (χ 2 =10.93, p=0.001). The predicted and actual risk of death at 12-month follow-up turned out to be comparable when assessing survival parameters according to the MAGGIC scale. (χ 2 =2.24, p=0.134). Conclusion. CCM therapy in some patients with CHF of non-ischemic etiology can lead to an improvement of all clinical and instrumental characteristics. At the same time, there is no effect of CCM on the prognosis of patients with CHF. This fact may suggest the need of additional studies with increased number of cases.

Objective. Evaluate efficacy and safety of cavutilide (Refralon) for pharmacological cardioversion in patients with recurrent atrial fibrillation and flutter (AF/AFL), in 90days blanking period of catheter ablation. Materials and methods. included 56 patients: 46 patients with recurrent paroxysmal AF/AFL and 10 patients with recurrent persistent AF/AFL. In 45 patients (80.3%), sinus rhythm (SR) restoration was performed within 7 days from the moment of catheter ablation. Intraoperative confirmation of pulmonary vein (PV) isolation was noted in 85.7% cases (n=48). After excluding contraindications, cavutilide was administrated in the intensive care unit according to a 4-stage protocol (5 µg/kg – 5 µg/kg-10 µg/ kg – 10 µg/kg). Effectiveness of pharmacological cardioversion was assessed as the fact of restoring SR and the fact of preservation of SR 24 hours after cavutilide administration. Safety points – QT prolongation, ventricular arrhythmogenic effects, pauses and bradyarrhythmias. Results. The overall effectiveness of cavutilide among all included patients reached 98.2% (n=55), and preservation of SR 24 hours after cavutilide administration was observed in 94.5% (n=53) patients. All the patients with recurrent persistent AF/AFL successfully restored and maintained SR 24 hours after cavutilide administration 100% (n=10). In patients with recurrent paroxysmal AF/AFL restoration of SR observed in 97.8% (n=45) and preservation of SR after 24 hours – in 93.4% (n=43), respectively. The effectiveness of cavutilide did not depend on the results of the catheter ablation. Recurrences of AF/AFL after SR restoration were more common in patients without successful PV isolation. QT prolongation >500ms observed in 8.9% (n=5) of cases, including 1 case of self-terminating torsade de pointes, managed by MgSO 4 infusion. Bradyarrhythmias that did not require urgent therapy were noted in 10.7% (n=6) of cases. Conclusion . Pharmacological cardioversion with Cavutilide (Refralon) is highly effective and safe method of SR restoration in patients with recurrent AF/AFL in 90days blanking period after catheter ablation.

Aim: To evaluate the safety and tolerance of single dose or repeated doses administration of domestic class III antiarrhythmic agent Refralon (cavutilide), tablets, by healthy volunteers; and to study it’s pharmacokinetics and absolute bioavailability.Material and Methods. Healthy male volunteers, aged 18 – 45 years were included in one of 7 cohorts: 1, 2, 4 и 6 mg PO, 1 mg IV (these cohorts included 6 people each), one cohort of 12 people who took 2 mg of the drug per day for 5 days, and one cohort of 6 menfor 10 days. Drug intake/injection, blood and urine tests, sampling for pharmacokinetic analysis, assessment of vital signs, ECG registration at specified points, Holter monitoring of ECG were performed in a hospital setting.Results. The study included 48 volunteers 32 ± 7,2 years old, mean weight 74,6 ± 4,7 kg. No significant changes in blood and urine tests and vital signs in any of cohorts were registered. Among cohorts of single dose oral intake only maximum dose of 6 mg caused persistent statistically significant increase of the duration of the QT and QTc intervals. In cohort of multiple intake of 2 mg of the drug statistically significant increase of the QT/QTc duration was noted with maximum value on 9-10 days. By this time balance between absorption and elimination processes was achieved.Conclusion. Duration of the QT/QTc intervals didn’t exceed reference values during the entire study in all cohorts of oral intake of Refralon, either single dose or repeated doses administration. Significant persistent increase of the duration of the QT and QTc intervals was registered only in cohort of maximum single dose of 6 mg intake and during intake of 2 mg of Refralon daily for 5-10 days. Stationary state was achieved by 8-10 day of Refralon intake.

Aim. To assess myocardial changes during left bundle branch block (LBBB) in patients with dilated cardiomyopathy (DCM) and in structurally normal hearts. Materials and methods. Seventy three patients with clinic-instrumental signs of DCM, were divided into 2 groups with LBBB (group 1; n=41) and without LBBB (group 2; n=32). Moreover, 15 patients with LBBB with no signs of structural heart diseases (group 3) and 10 healthy subjects were included in the study. Fibrosis assessment and the inflammation detection was performed by cardiovascular magnetic resonance (CMR). The inflammation in 15 patients from group 1 and 16 patients from group 2 was confirmed by endomyocardial biopsy (EMB). Moreover, the level of transforming growing factor β1was assessed in serum of all patients and healthy subjects (TGF-β1). Results. The diffuse inflammatory process was defined in 46.7% cases of group 1 according to EMB data. The frequency of inflammation detection in groups 1 and 2 was comparable in EMB analyses (p=0,64) and CMR analyses (12,2% positive cases in group 1 vs 50% in group 2; p=0,18). The frequency of focal left ventricular fibrosis and intramural scar in the interventricular septum (“stria”) was also comparable in groups 1 and 2: 16 (39%) positive cases with focal fibrosis in group 1 versus 17 (53%) cases in group 2; p=0,35 and 6 (14,6%) cases with intramural scar in group 1 versus 7 (22%) in group 2; p=0,12. Patients from group 3 demonstrated no late gadolinium enhancement on CMR images but increased TGF-β1 level in the serum. Conclusion. Focal myocardial fibrosis is not related to the LBBB. Patients with idiopathic LBBB are characterized by increased TGF-β1 level with no myocardial fibrosis. Diffuse inflammation in LBBB-DCM patients may contribute to the progression of systolic dysfunction but is not the reason for LBBB formation.

Genetic causes are increasingly found to be responsible for the development of sudden death in young people. Since 2009, pathogenic mutations in RBM20 gene were recognized as an important cause of dilated cardiomyopathy (DCM) and sudden cardiac death (SCD). The high risk of malignant ventricular arrhythmias in RBM20 -cardiomyopathy has made these patients potential candidates for the implantable cardioverter-defibrillator for primary prevention of SCD. The presented clinical case of malignant pathogenic mutation in the RBM20 gene demonstrates different phenotypes, including DCM, SCD and asymptomatic forms in one family. Moreover, for the first time we described the presence of prolonged QT interval due to the fusion with U wave on ECG in carries of this malignant familial mutation. The prolonged QT interval may contribute to the development of ventricular arrhythmias and the increased risk of SCD in patients with this rare genetic pathology.

Aim Evaluating the efficacy and safety of early administration of antirecurrence antiarrhythmic therapy (AAT) following restoration of sinus rhythm (SR) with refralon.Aim Evaluating the efficacy and safety of early administration of antirecurrence antiarrhythmic therapy (AAT) following restoration of sinus rhythm (SR) with refralon.Material and methods The study included 247 patients with atrial fibrillation/atrial flutter (AF/AFL) (142 men) who underwent pharmacological cardioversion (PCV) with refralon. A 4-step schedule of drug administration was used (successive intravenous infusions at doses of 5, 5, 10, and 10 µg/kg; maximum total dose was 30 µg/kg). Patients who recovered SR and had no contraindications were prescribed antirecurrence AAT in the early (≤24 h; n=101) or delayed (≥24 h; n=95) period. Lappaconitine hydrobromide, propafenone, and sotalol were administered orally as the antirecurrence therapy. The decision on the time of initiating ATT and the choice of the drug and its dose was taken by the attending physician individually. The safety criteria included a prolonged PQ interval >200 ms; second- or third-degree atrioventricular block; QRS complex duration >120 ms; QT prolongation >500 ms; and heartbeat pauses >3 s. The efficacy criteria included the absence of sustained recurrence of AF/AFL after initiation of AAT and the duration of hospitalization after PCV. Patients were followed up during the study until they were discharged from the hospital.Results SR was recovered in 229 (92.7 %) patients. In the group of early AAT initiation, a PQ duration >200 ms was observed in 8 (7.9 %) patients, whereas in the group of delayed AAT initiation, in 7 patients (7.4 %; p=1.000). A wide QRS complex >120 ms was recorded in 1 (1.1 %) patient of the delayed AAT initiation group and in none of the patients of the early AAT initiation group (p=0.485). Ventricular arrhythmogenic effects and QT prolongation >500 ms were not detected in any patient. Numbers of early AF recurrence did not differ in the groups of early and delayed AAT initiation: 6 (5.9 %) vs. 5 (5.3 %), respectively (p=1.000). Median duration of hospitalization after PCV was 4 days in the group of early AAT initiation and 5 days in the group of delayed AAT initiation (р=0.009).Conclusion Early initiation of the refralon AAT does not increase the risk of drug adverse effects and reduces the duration of stay in the hospital.

Aim . To compare the efficacy and safety of chemical cardioversion (CCV) with refralon and amiodarone in patients with paroxysmal atrial fibril­lation and flutter (AF/AFL). Material and methods . Fifty five patients (mean age, 65±11 years) with paroxysmal AF/AFL were included. All patients underwent a preliminary examination to rule out contraindications to CCV. Further, patients were randomized into groups of refralon (n=30) and amiodarone (n=28), respectively. CCV with refralon was carried out as follows: administration in doses of 5-5-10-10 µg/kg at intervals of 15 minutes. Patients of the second group were intravenously injected with amiodarone at a dose of 5 mg/kg of body weight for 20-60 minutes, depending on the drug tolerability. If AF/AFL persists after 60 minutes, infusion of amio­darone 100 mg/hour until restoration of sinus rhythm (SR) or reaching a dose of 1200 mg/day. Treatment efficacy was assessed by SR reco­very, absence of AF/AFL recurrence, and arrhythmia relief time, and safety was assessed by detection of ventricular arrhythmogenic effects, bradyarrhythmias, blood pressure reduction, and QT interval prolongation. The follow-up period lasted 24 hours. Results . SR was restored in 96,7% (n=29) of patients in the refralon group, of which 56,7% (n=17) after a dose of 5 mcg/kg. In the amio­darone group, SR was restored in 57,1% (n=16) of patients (p<0,001). The arrhythmia relief time in the refralon group was 14 [7;23] min, while in the amiodarone group — 150 [82;240] min (p<0,001). There were no significant differences in the incidence of bradyarrhythmias, lowering blood pressure, and QT prolongation in the groups. Conclusion . Refralon demonstrates a higher efficiency and lower time to AF/AFL relief compared with amiodarone, while in most patients, SR recovery occurs after the administration of the lowest doses, which ensures CCV safety.

Aim. To develop diagnostic criteria for proximal left bundle branch block (LBBB) based on non-invasive methods and to determine the significance of these criteria in predicting the effect of cardiac resynchronization therapy (CRT).Material and methods. To develop criteria, 58 patients (21 men, mean age, 76,1±7,1 years) with LBBB occurred immediately after transcatheter aortic valve implantation (TAVI) were included. To assess the significance of the developed criteria, the second group included 22 patients (11 men, mean age, 57,9±9,3 years) with dilated cardiomyopathy (DCM), who had indications for CRT. The effectiveness of CRT was assessed by echocardiography 6 months after implantation. All patients in the DCM group and 15 patients in the TAVI group underwent superficial epiand endocardial non-invasive mapping using Amycard 01C EP Lab (EP Solutions SA, Switzerland). Patients in the DCM group underwent contrast-enhanced cardiac magnetic resonance imaging (MRI) before device implantation.Results. The criteria for proximal LBBB included 3 electrocardiographic features: QRS complex >130 ms in women and 140 ms in men, QSor rS-configuration in V1 lead, notch in two or more lateral leads (I, avL, V5, V6), and 2 mapping criteria: characteristic location of block line and delayed activation point. In the DCM group, the criteria were positive in 13 of 22 patients (59%). The developed criteria for proximal LBBB showed a relatively strong, significant relationship with the positive effect of CRT (сhi-square test =5,46, p=0,02, Cramer test =0,5, odds ratio (OR)=15,0, 95% confidence interval (CI), 1,32-169,9, p=0,002). An additional analysis showed that both the criteria for proximal block and CRT effect are associated with myocardial fibrosis according to MRI. In particular, intramural stria-shaped contrast accumulation in the interventricular septum leads to a change in characteristic of proximal block mapping phenomena — displacement of delayed activation point (chi-square test =13,9, p<0,001, Cramer test =0,79) and displacement or absence of conduction block lines (chi-square test =6,92, p=0,009, Cramer test =0,56) and prevents the CRT effect (OR =8,67, 95% CI, 1,05-71,57 p=0,03).Conclusion. Proximal LBBB is only one of the factors determining the effectiveness of CRT. Proximal LBBB may mask significant myocardial structural changes that prevent the CRT success.

Russian Society of Cardiology, National Society of Preventive Cardiology

This review summarizes the available information on the epidemiology and prognosis of patients with left bundle branch block (LBBB), morphological alterations of the myocardium both resulting in and ensuing LBBB, cardiac biomechanics in LBBB, and possibilities of its correction.

This work aimed to study the efficacy and safety of the class III antiarrhythmic agent cavutilide (Niferidil, Refralon) for pharmacological cardioversion in patients with paroxysmal and persistent atrial fibrillation (AF) and heart failure (HF). Methods and Results: In this retrospective cohort study, 58 patients with stable HF (aged 69 [61;73] years, 30 males, 78% with persistent AF) and 274 patients without HF (aged 63 [57;70] years, 196 males, 56% with persistent AF) were included. The median AF duration in the group with HF was 35.5 [10.6;124] days, and that in the group without HF was 14.5 [3.6;90] days. All patients received 5–30 µg/kg cavutilide intravenously in one to four (if needed) boluses of 5–5–10–10 µg/kg at 15 min intervals. Subsequent boluses were not administered if the patient’s sinus rhythm (SR) was restored or if bradycardia, QT prolongation > 500 ms or evidence of proarrhythmia was observed. Holter electrocardiogram monitoring was started before infusion and was continued for 24 h. The main criterion for an antiarrhythmic effect was sinus rhythm restoration within 24 h of the initial bolus. Results: Cavutilide converted AF to SR in 37.9% of patients with HF after bolus 1 (5 µg/kg), in 58.6% after bolus 2 (cumulative dose = 10 µg/kg), in 74% of cases after bolus 3 (cumulative dose = 20 µg/kg) and in 92.8% of cases after bolus 4 (cumulative dose = 30 µg/kg). Cavutilide was effective in 89% of cases with persistent AF with a median duration of 70.5 [30;159] days and in 92% of cases with paroxysmal AF with a median duration of 36 [24;102] h. In the group of patients without HF, the effectiveness of bolus 1 was 36.9%, that of the bolus 2 was 58%, that of the bolus 3 was 77% and that of the bolus 4 was 90.1%. Cavutilide restored SR in 90% of patients with persistent AF with a median duration of 82.5 [28;180] days and in 90% of cases with paroxysmal AF with a median duration of 50 [24;120] h. No statistically significant difference in the probability of SR restoration or the effectiveness of each bolus of cavutilide was found between patients with and without HF. The median time to restoration of SR in patients with HF was 23 [11;55] min, and that in patients without HF was 22 [10;45] min (p = 0.424). No cases of symptomatic/severe bradycardia were observed in either group. QT prolongation over 500 ms after cavutilide injection was registered in 19% of patients without HF and in 15.5% of those with HF (p = 0.58). Short runs of Torsade de pointes tachycardia occurred in one patient (0.4%) without HF after 10 µg cavutilide administration and were successfully treated with MgSO4. Conclusions: Cavutilide demonstrated a high likelihood of AF conversion to SR in paroxysmal (92%) and persistent (89%) arrhythmia and HF. Concomitant HF and its severity do not affect the efficacy and safety of cavutilide.

Aim. To study the effectiveness of “extended” cryoballon ablation in patients with a persistent form of atrial fibrillation (AF) and to determine the risk factors for AF recurrence after cryoablation. Methods. The study included 89 patients (62±10 years, 24 [27%] men) with a persistent form of AF. The patients were randomized into two groups: in the 1st, the pulmonary veins (PV) cryoablation was performed (n=48 [53.9%]); in the 2nd, the PV cryoablation was performed in combination with cryoablation of the posterior wall of the left atrium (n=41 [46.1%]). The number of patients at high risk of thromboembolic events predominated in Group 2 (p=0,03). There is a high frequency of taking antiarrhythmic drugs of class III in this group (p=0.018). The follow-up period was 12 months. Clinical efficacy was assessed during a survey and daily ECG monitoring at face-to-face visits after 3, 6 and 12 months. Results. Antral isolation of PV was achieved in all 89 (100%) patients in both groups. In group 2, the average number of applications in the posterior wall of the PV was 10 [9; 13]. The effectiveness of cryoablation in group 1 by the end of the 12-month follow-up period was 54.2%, in group 2 - 56.1%. The complication rate (6.7%) in both groups did not differ statistically (p=0.683). The risk of arrhythmia recurrence didn’t depend on the strategy of cryoablation in postablation period (p=0.834). When conducting a single-factor analysis, a statistically significant effect on the probability of AF recurrence in the period of 3-12 months in group 1 was caused by AF recurrence in the blind period (95% confidence interval (CI): 1.5-27.7, p=0.013), in group 2 belonging to the female sex (95% CI: 1.2-24.6, p=0.032) and AF relapse in the blind period (95% CI: 1.5-128.5, p=0.020). During multivariate analysis in group 2, a statistically significant influence on the risk of AF recurrence in the period of 3-12 months was exerted by belonging to the female sex (hazard ratio (HR) 7.84; 95% CI 1478-42,23; p=0.016) and the presence of early AF recurrence (HR 20.36; 95% CI 1.99-208.23; p=0.011). Conclusion. Extended cryoablation in terms of efficiency and safety was comparable with the standard cryoablation. Early recurrence of AF (in the first 3 months after the intervention) turned out to be an independent risk factor for AF recurrence in the long-term period up to 12 months after cryoablation in both groups.