Second-generation Cryoballoon Ablation Research Articles

Long-term recurrence-free survival following second-generation cryoballoon ablation for persistent atrial fibrillation: role of the autonomic nervous system

Abstract Background The cardiac autonomic nervous system (ANS) plays a pivotal role in the regulation of atrial fibrillation (AF). Cryoballon (CB)-guided pulmonary vein isolation (PVI) is an established treatment for AF. Purpose In our present study we evaluated the impact of vagal reactions (VRs), as a surrogate parameter for ANS modulation, on the long-term outcome of CB-ablation in patients with persistent AF (PERS AF). Methods Data from consecutive PERS AF patients undergoing primary CB-guided PVI for symptomatic drug refractory AF between 2013-2023 were analysed. VRs were defined as bradycardia < 40 beats/min, asystole or higher-degree atrioventricular block. Long-term follow-up data were assessed. AF-recurrence was defined as AF lasting > 30 seconds beyond a 3-month blanking period. Results A total of 250 consecutive patients (mean age 63.9±10.0 years, 30% female) were included. VRs were recorded in 61 patients (24%, mean age 64.2±13.0 years, 30% female). The mean follow-up duration amounted to 84±14 months. Within this observation period 101 patients (40%) developed AF-recurrence. Re-ablation procedures were performed in 61 patients (60%). Patients with PVI-associated VRs presented with a significantly higher estimated AF-free survival rate (log-rank p-value < 0.001) (Figure 1) and a significantly longer median AF-free survival time (75 months, interquartile range (IR) 63-92 months) compared to those without (69 months, IR 13-79 months) (p=0.002). Beyond that Kaplan-Meier plot analyses revealed significant gender differences (Figure 1). Multivariate cox regression analyses confirmed VRs (Confidence interval (CI) 0.294-0.838, Hazard Ratio (HR) 0.497, p=0.009) and male gender (CI 0.352-0.781, HR, 524, p=0.001) as independent predictors (IPs) for AF-free-survival. Conclusion CB-ablation procedure associated VRs and male gender seem to be associated with a favorable long-term outcome in PERS AF. Further studies are warranted to verify our observations.Kaplan Meier plot on long-term AF-free s

Comparative analysis of pulsed-field and cryoballoon ablation in octogenarians with atrial fibrillation: a multicenter study

Abstract Background The prevalence of atrial fibrillation (AF) increases with advancing age, and AF contributes to higher rates of stroke, dementia, heart failure, and mortality. Catheter ablation is recognized as an effective treatment for AF; however, data regarding its efficacy in octogenarians are limited. Cryoballoon ablation (CBA) has been reported to be safe and effective in this age group. Recently, single-shot devices using pulsed-field energy have been developed, offering a tissue-specific effect. However, data on the safety and effectiveness of this novel pulsed-field ablation (PFA) in octogenarians are still insufficient. Purpose This study aims to evaluate the procedural outcomes and complications of PFA in octogenarians with AF, in comparison to CBA, from 3 high-volume European centers. Methods We retrospectively enrolled patients who underwent PFA via the FarapulseTM system from January 2022 to June 2023, and those who underwent second-generation CBA from January 2015 to June 2023. Results A total of 176 patients (PFA group: 63, CBA group: 113) were included. The PFA group had a higher proportion of patients with persistent AF (p=0.03) and undergoing a repeat procedure (p<0.01). (Table 1) Unlike CBA, PFA procedures involved additional extrapulmonary targets, such as posterior wall and mitral isthmus. Nonetheless, procedure time was similar between groups. There were no significant differences in complications but phrenic nerve palsy was not observed in the PFA group (Table 2). Conclusions PFA for octogenarians provides the possibility to target additional extrapulmonary sites with equivalent procedural times and safety compared to CBA, without the concern of phrenic nerve palsy.Table 1Table 2

Safety and Efficacy of Second-Generation Cryoballoon Ablation in Patients Aged over 75 Years

Objective: The use of second-generation cryoballoon (CB2) for pulmonary vein isolation (PVI) in atrial fibrillation (AF) ablation therapy is common. This study aimed to compare the safety and efficacy of CB2 ablation for PVI in AF patients aged 75 years and older to those under 75 years old. Methods: A retrospective, observational study was conducted, including AF patients who underwent CB2 for PVI between January 2018 and December 2020 at our center. The patients were divided into two groups based on age: those aged 75 years and older (elderly group) and those under 75 years (control group). Procedural characteristics, complications, and one-year follow-up outcomes were compared between the two groups using Student's t-test or the chi-square test for univariate analysis. Results: A total of 156 AF patients treated with CB2 for PVI were included in the study, with 78 patients aged 75 years and older (elderly group, mean age = 78 years) and 78 patients aged under 75 years (control group, mean age = 66 years). The PVI procedure duration was 86.2 ± 25.8 minutes for the elderly group and 83.2 ± 20.8 minutes for the control group (p = 0.413). The elderly group showed a higher trend of complications (8/78, 10.3%) compared to the control group (2/78, 2.6%) (p = 0.049), although no serious complications were observed. One-year follow-up revealed that approximately 80% of patients in both groups did not experience AF recurrence (p = 0.656). Conclusion: CB2 ablation for PVI appears to be safe and effective in AF patients aged 75 years and older, with outcomes comparable to those in younger patients. However, special attention should be given to venous puncture in elderly patients.

Treatment of atrial fibrillation with second-generation cryoballoon followed by contact-sensing radiofrequency catheter ablation for arrhythmia recurrences-results of a 5-year follow-up.

The aim of this study was to report the long-term follow-up results of cryoballoon (CB) ablation in patients with atrial fibrillation. All consecutive patients who underwent second-generation CB ablation from February 2015 to December 2017 were included in our study. In all procedures, we used a 28-mm CB placed via a single transseptal puncture guided by intracardiac ultrasound. A 20-mm octapolar intraluminal circular catheter was used for intracardiac recordings. A single 180-s freeze strategy was employed. Repeated procedures were performed with a 3D mapping system and radiofrequency catheters. A total of 126 patients (69.8% male, mean age 57 ± 11years), of which 77.0% had paroxysmal atrial fibrillation (PAF), were included in the study. After a 5-year period, 52.4% of patients were in sinus rhythm without AF recurrence, off antiarrhythmic drugs. A total of 61.9% of patients were free of AF recurrence when redo PVI procedures were performed. When accounting for redo pulmonary vein isolation and antiarrhythmic drugs, a total of 73.8% of the patients were without AF recurrence in long-term follow-up. The patients who underwent redo pulmonary vein isolation procedures had statistically significant lower rates of AF recurrence (p = 0.006). In patients with PAF, long-term success rates improved from 62.9 to 79.4% for patients who underwent the redo procedure (p = 0.020). In patients with persistent atrial fibrillation (PersAF), success rates went up from 41.4 to 55.1% for patients with single or repeated PVI procedure (p = 0.071). In the whole cohort, a total of 3 (2.4%) procedure-related major complications occurred which included persistent PNP, arterial pseudoaneurysm, and arteriovenous fistula. Our data suggest a favorable long-term safety and efficacy profile of second-generation CB ablation. In the mixed paroxysmal and persistent population, up to 73.8% of patients remained free of AF recurrence in the 5-year follow-up, when accounting for redo procedures and AADs. Only 2.4% of patients experienced major complications of the ablation procedure, none with permanent sequelae.

Cryoballoon ablation for atrial fibrillation in octogenarians: a propensity score-based analysis with a younger cohort.

In terms of safety and efficacy, cryoballoon ablation (CB-A) has become a valid option for achieving pulmonary vein isolation (PVI) in patients affected by symptomatic atrial fibrillation. However, CB-A data in octogenarians are still scarce and limited to single-centre experiences. The present multicentre study aimed to compare the outcomes and complications of index CB-A in patients older than 80 years with a cohort of younger patients. We retrospectively enrolled 97 consecutive patients aged ≥80 years who underwent PVI using the second-generation CB-A. This group was compared with a younger cohort of patients using a 1:1 propensity score matching. After the matching, 70 patients from the elderly group were analysed and compared with 70 younger patients (control group). The mean age was 81.4 ± 1.9 years among octogenarians and 65.2 ± 10.2 years in the younger cohort. The global success rate after a median follow-up of 23 [18-32.5] months was 60.0% in the elderly group and 71.4% in the control group (P = 0.17). Phrenic nerve palsy was the most common complication occurring in a total of 11 patients (7.9%): in 6 (8.6%) patients in the elderly group and in 5 patients (7.1%) in the younger group (P = 0.51). Only two (1.4%) major complications occurred: one (1.4%) femoral artery pseudoaneurysm in the control group, which resolved with a tight groin bandage, and one (1.4%) case of urosepsis in the elderly group. Arrhythmia recurrence during the blanking period and the need for electrical cardioversion to restore sinus rhythm after PVI were found to be the only independent predictors of late arrhythmia relapses. The present study showed that CB-A PVI is as feasible, safe and effective among appropriately selected octogenarians as it is in younger patients.

Five-Year Experience of Second-Generation Cryoballoon Ablation for Paroxysmal Atrial Fibrillation from a Tertiary Cardiac Care Center of Pakistan: A Retrospective Chart Review

Objectives: The study aimed at assessing the outcome of pulmonary vein isolation (PVI) using second-generation cryoballoon, Arctic Front Advance, Medtronic (CB-Adv) as a rhythm control strategy for drug-resistant paroxysmal atrial fibrillation (PAF) in a cardiac tertiary care center of Pakistan. Methodology: Fifty patients had PVI with CB-Adv for symptomatic drug-resistant PAF at the National Institute of Cardiovascular Diseases, Karachi, Pakistan, during 2017-2022. Patients were followed-up in the clinic on the 1st, 3rd, and 6th month after the ablation. Twenty-four hours of Holter monitoring of electrocardiogram was obtained on each visit. We conducted a retrospective chart review after approval from the ethical review committee. We collected all the patients' demographic and clinical data, procedural results, and reports of Holter monitoring. The primary outcome was successful PVI and freedom from atrial tachyarrhythmia (Ata) on a 6-month follow-up. Results: We enrolled all 50 patients (34 male, 68%; mean age 55.14 ± 7.94 years) treated with PVI using CB-Adv. The mean duration of symptoms was 30.28 ± 13.48 months. PVI with CB-Adv was found to be curative in 49 patients (98%). Following the procedure, pericardial effusion was found in one patient (2%), whereas one patient (2%) had a retroperitoneal hematoma. On a six-month follow-up, only one patient (2%) had a recurrence of Ata, which was PAF. Conclusion: Our experience of PVI with CB-Adv has shown a high success rate of the procedure for rhythm control in patients who have PAF, which is resistant to antiarrhythmic drugs (AADs).

Comparison of Second-Generation Cryoballoon Ablation and Quantitative Radiofrequency Ablation Guided by Ablation Index for Atrial Fibrillation.

We compared the efficacy and complication rates of quantitative radiofrequency ablation guided by ablation index (RFCA-AI) with those of second-generation cryoballoon ablation (CBA-2). Consecutive patients (n = 230) with symptomatic atrial fibrillation (AF) undergoing a first ablation CBA-2 (92 patients) or RFCA-AI (138 patients) procedure were enrolled in this study. The late recurrence rate in the CBA-2 group was higher than that in the RFCA-AI group (P = .012). Subgroup analysis showed the same result in patients with paroxysmal AF (PAF) (P = .039), but no difference was found in patients with persistent AF (P = .21). The average operation duration in the CBA-2 group (85 [75-99.5] minutes) was shorter than that in the RFCA-AI group (100 [84.5-120] minutes) (P < .0001), but the average exposure time (17.36(13.87-22.49) vs 5.49(4.00-8.24) minutes) in the CBA-2 group and X-ray dose (223.25(149.15-336.95) vs 109.15(80.75-168.7) mGym) were significantly longer than those in RFCA-AI group (P < .0001). Multivariate logistic regression analysis showed that left atrial diameter (LAD), early recurrence, and methods of ablation (cryoballoon ablation) were independent risk factors for late recurrence after AF ablation. Early recurrence of AF and LAD were independent risk factors for predicting late recurrence after AF ablation.

WITHDRAWN: Comparison of second-generation cryoballoon ablation and quantitative radiofrequency ablation guided by ablation index for atrial fibrillation.

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Predictors of late pulmonary vein reconnection in patients with arrhythmia recurrence after cryoballoon ablation-per vein analysis including cardiac computed tomography-based anatomic factors.

To identify predictors of individual late pulmonary vein (PV) reconnection after second-generation cryoballoon (CB2) ablation. Anatomic indicators of late pulmonary vein reconnection (LPVR) post-CB2 ablation have not yet been studied on an individual PV level, nor weighed against clinical and procedural factors. Clinical, procedural, and PV anatomic data from 125 patients with a repeat procedure for arrhythmia recurrence after index CB2 ablation were analyzed. Preprocedural computed tomography (CT) evaluated 486 PVs for measurement of size; shape (ovality index); carina width; and orientation angle in frontal (superior/inferior) and transversal (anterior/posterior) plane (with horizontal line 0° as reference and upper/lower half circle as positive/negative value, respectively). Durable isolation in all PVs was demonstrated in 50/125 (40%) patients. Late reconnection rates at the different PVs were as follows: 16% left superior (LS), 12% left inferior (LI), 17% right superior (RS), and 31% right inferior (RI) PV. Multivariable analysis performed per vein showed following independent determinants predicting LPVR: ovality index [odds ratio (OR) 1.61, 95% confidence interval (CI) 1.07-2.41, P = 0.022] and carina width (OR 0.75, CI 0.59-0.96, P = 0.024) for LSPV; carina width (OR 0.71, CI 0.53-0.95, P = 0.020) for LIPV; frontal angle (OR 0.91, CI 0.87-0.95, P < 0.001) for RIPV; and transversal angle (OR 1.15, CI 1.03-1.31, P = 0.032) for RSPV. Cardiac CT-based evaluation of anatomic PV characteristics presented higher predictive value compared to clinical and procedural variables for individual LPVR after CB2 ablation. Pre-procedural identification of unfavourable PV anatomy might be important to tailor the ablation approach.

Cryoballoon ablation of persistent atrial fibrillation for de novo pulmonary vein isolation: a single-center follow-up study.

Pulmonary vein isolation (PVI) alone for persistent atrial fibrillation (PersAF) remains controversial. The characteristics of cryoballoon ablation (CBA) to treat PersAF and the blanking period recurrence are underreported. This study retrospectively analyzed patients with PersAF undergoing second-generation CBA for de novo PVI. The post-procedural efficacy and survival analysis were compared between patients with different PersAF durations. The multivariate Cox regression analysis was used to detect the risk factors for recurrence. Early and long-term recurrence were analyzed relative to each other. A total of 329 patients were enrolled, with a median PersAF duration of 4.0 months (interquartile range: 2.0-12.0 months); 257 patients (78.1%) were male. Kaplan-Meier analysis of freedom from atrial fibrillation recurrence at 12, 24, and 30 months showed 71.0%, 58.5%, and 54.9%, respectively. Early PersAF had a relatively favorable survival rate and a narrow P-wave duration of restoring sinus rhythm compared with that of PersAF lasting more than three months (P < 0.05). The multivariate Cox regression analysis revealed that PersAF duration and left atrial anteroposterior diameter ≥ 42 mm were the risk factors for atrial fibrillation recurrence after CBA [hazard ratio (HR) = 1.89, 95% CI: 1.01-1.4, P = 0.042; HR = 3.6, 95% CI: 2.4-5.4, P < 0.001, respectively]. The blanking period recurrence predicted the long-term recurrence (P < 0.0001). CBA of PersAF had safety and efficacy to reach de novo PVI. The PersAF duration and left atrial size were risk factors for atrial fibrillation recurrence after CBA. Blanking period recurrence was associated with long-term recurrence.

Evaluation of Isolation Area, Myocardial Injury and Left Atrial Function Following High-Power Short-Duration Radiofrequency or Second-Generation Cryoballoon Ablation for Atrial Fibrillation.

This randomized study aims to compare the left atrial (LA) lesion size, function, and tissue damage following pulmonary vein isolation (PVI) by high-power short-duration (HPSD) radiofrequency (RF) and second-generation cryoballoon (CB2) ablation. We enrolled 40 patients with paroxysmal atrial fibrillation who underwent PVI by HPSD RF (n = 21) or CB2 (n = 19). Every patient underwent LA CT angiography and transthoracic echocardiography (TTE) to assess the LA anatomy and function. Biomarker levels (hs-cTnT, hs-CRP, LDH) were compared pre- and post-procedurally. Pre- and post-ablation high-density mapping (HDM) was performed. The isolation area was defined under 0.2 mV bipolar voltage (low voltage area, LVA). We calculated the post-PVI LVA/LA surface ratio using LA CT-HDM merge images. At 3-month follow-up, TTE was performed to assess the changes in LA function. Post-ablation hs-cTnT level was significantly higher in the RF group (RF: 1249 ± 469 ng/L, CB2: 995 ± 280 ng/L, p = 0.024). Post-PVI hs-CRP (RF: 9.53 ± 10.30 mg/L, CB2: 12.36 ± 5.76 mg/L, p = 0.034) and LDH levels (RF: 349.9 ± 65.6 U/L, CB2: 451.6 ± 91.3 U/L, p < 0.001) were significantly higher following CB2 ablation. Post-PVI LVA/LA surface ratios were 8.37 ± 6.42% in the RF group and 13.58 ± 8.92% in the CB2 group (p = 0.022). LA function did not change significantly after the PVI procedure. Our data indicate that second-generation cryoballoon ablation produces a significantly larger LA lesion size compared to “point-by-point” HPSD radiofrequency. Both techniques preserve LA function. The myocardial component of tissue loss appears to be higher using HPSD radiofrequency ablation, with less collateral damage.

Long-term Outcomes after Second-Generation Cryoballoon Ablation of Atrial Fibrillation and Analysis of Risk Factors Related to Recurrence

Objective: This study is aimed to analyze the long-term safety and effectiveness of second-generation cryoballoon (CB2) ablation in the treatment of atrial fibrillation (AF). Methods: Data from 760 consecutive patients in the Department of Cardiology, General Hospital of Northern Theater Command from August 2016 to December 2018 with drug-refractory symptomatic AF undergoing pulmonary vein isolation (PVI) using CB2 were assessed. Procedure-related safety and freedom from AF and atrial flutter/atria tachycardia through 3 years were determined. The risk factors related to atrial tachyarrhythmia recurrence were analyzed. Results: Acute PVI was achieved in 100% of the 760 patients. Radiofrequency application for additional focal ablation was needed in 11 (1.4%) patients and for 14 pulmonary veins (0.5%, 14/(760 × 4)) to achieve PVI. A total of 748 patients, including 539 with paroxysmal AF (PAF) and 209 with persistent AF (SAF) completed the follow-up, and only 12 (1.6%) patients were lost. The mean follow-up duration was (19 ± 8) months. The rate of major complications was 0.9%, including 0.8% of right phrenic nerve injury, which resolved before discharge. Freedom from all tachyarrhythmias was achieved in 75.0%, 69.4%, and 63.2% of patients with PAF, respectively, at 12-, 24-, and 36-month follow-up, and in 75.1%, 67.4%, and 60.9% for SAF, with no significant differences between the PAF and SAF groups. AF course and the rate of body weight gain were independent risk factors for recurrence at 12 months after ablation (P = 0.001 and P = 0.009, respectively). Conclusion: PVI using CB2 has a high acute success rate and good safety in the treatment of PAF and SAF. Long course of AF and weight gain after ablation were independent risk factors for recurrence.

Twelve-month efficacy of second-generation cryoballoon ablation for atrial fibrillation performed at community hospitals: results of the German register on cryoballoon ablation in local hospitals (regional).

The 12-month follow-up (F/U) efficacy of CBA PVI performed at community hospitals for treatment of symptomatic paroxysmal and persistent atrial fibrillation (AF) is unknown. This study determined the 12-month efficacy of pulmonary vein isolation (PVI) using cryoballoon ablation (CBA) performed at community hospitals with limited annual case numbers. This registry study included 983 consecutive patients (pts) from 19 hospitals, each with an annual procedural volume of < 100 PVI procedures/year. Pts underwent CBA PVI for paroxysmal AF (n = 520), persistent AF (n = 423), or redo PVI (n = 40). The primary endpoint was frequency of documented recurrent AF, the occurrence of atrial flutter or tachycardia following a 90-day period after the index ablation and up to 12months. The frequency of repeat ablation was determined. Isolation of all PVs was documented in 98% of pts at the end of the procedure. Twelve-month F/U data could be obtained in 916 pts. A 24-h ECG registration was performed in 641 pts (70.0%); in 107 pts (16.7%) of them, recurrent AF was documented. The primary endpoint was met in 193 F/U pts (21.1%). It occurred in 80/486 F/U pts with paroxysmal AF (16.4%), and in 107/390 F/U pts with persistent AF (27.4%). Redo PVI was performed in 71 pts (7.8%), and atrial flutter ablation was performed in 12 pts (1.4%). CBA PVI for paroxysmal or persistent AF can be performed at community hospitals with adequate rates of 12-month symptom freedom and arrhythmia recurrence. The study was registered at the German register of clinical studies (DRKS00016504).

Durability of pulmonary vein isolation following cryoballoon ablation: lessons from a large series of repeat ablation procedures

Abstract Funding Acknowledgements Type of funding sources: None. Background The cryoballoon technology has been widely proven to be effective in achieving acute pulmonary vein (PV) isolation and favorable clinical outcome. To date, little information is still available about occurrence of late PV reconnection after cryoballoon ablation. Purpose To assess the rate of durable PV isolation following cryoballoon ablation of atrial fibrillation in the setting of repeat procedures. Methods and Results A total of 154 consecutive patients (90 male, 58.4%; mean age 60.6±12.6 years) underwent a repeat procedure, after a mean 21.5±12.4 months (median 14 months), after index ablation using the 28-mm second-generation cryoballoon. All repeat ablations were performed using a 3-dimensional electro-anatomical mapping system. Among all 590 PVs, including 26 left common ostiums (LCOs), 99 (16.8%) showed a PV reconnection in 86 patients (1.15 per patient). Persistent PV isolation could be documented in 491 of 590 PVs (83.2%). In 68 of 154 patients (44%), all PVs were electrically isolated. In the multivariable analysis, balloon nadir temperature (p&amp;lt;0.01) and time to PV isolation (P=0.02) independently predicted late PV reconnection. Conclusions The rate of late PV reconnection after second-generation cryoballoon ablation was low (1.15 PVs/patient). Globally, the rate of durable PV isolation assessed during repeat procedures was 83.2%. The balloon nadir temperature and faster time to isolation were independently associated with durable PV isolation.

A Systematic Review and Meta-Analysis of the Direct Comparison of Second-Generation Cryoballoon Ablation and Contact Force-Sensing Radiofrequency Ablation in Patients with Paroxysmal Atrial Fibrillation.

The superiority of second-generation cryoballoon (2G-CB) ablation versus contact force-sensing radiofrequency (CF-RF) ablation in patients with paroxysmal atrial fibrillation (AF) was assessed in this systematic review and meta-analysis. Freedom from atrial tachyarrhythmias (ATAs) (OR = 0.89; 95% confidence interval [CI] = 0.68 to 1.17; p = 0.41), freedom from AF (OR = 0.93; 95% CI = 0.65 to 1.35; p = 0.72), and acute pulmonary vein isolation (PVI) (OR = 1.17; 95% CI = 0.54 to 2.53; p = 0.70) between 2G-CB ablation and CF-RF ablation were not different. The procedure time for the 2G-CB ablation was shorter (MD = −18.78 min; 95% CI = −27.72 to −9.85 min; p < 0.01), while the fluoroscopy time was similar (MD = 2.66 min; 95% CI = −0.52 to 5.83 min; p = 0.10). In the 2G-CB ablation group, phrenic nerve paralysis was more common (OR = 5.74; 95% CI = 1.80 to 18.31; p = < 0.01). Regarding freedom from ATAs, freedom from AF, and acute PVI, these findings imply that 2G-CB ablation is not superior to CF-RF ablation in paroxysmal AF. Although faster than CF-RF ablation, 2G-CB ablation has a greater risk of phrenic nerve paralysis.

Comparison of Using Second-Generation Cryoballoon and Radiofrequency Catheter for Atrial Fibrillation Ablation in Patients With the Common Ostium of Inferior Pulmonary Veins.

Aims: To compare the procedural outcomes of cryoballoon ablation (CBA) and radiofrequency ablation (RFA) in atrial fibrillation (AF) patients with the common ostium of inferior pulmonary veins (COIPV) and to explore the effect of COIPV on CBA performance through the assessment of anatomical factors.Methods: A total of 18 AF patients with COIPV were included. Pulmonary vein isolation (PVI) was performed with second-generation CBA or RFA. The anatomical characteristics of COIPV and procedural outcomes were collected.Results: The prevalence of COIPV was 0.82% in the enrolled population. PVI was achieved in all pulmonary veins (PVs) without any complications. The “tricircle” strategy was applied for RFA, and the segmental freeze strategy was performed for CBA. Compared with RFA, CBA had shorter procedural time (median: 53.0 vs. 78.0 min, p < 0.001) and longer fluoroscopy time (median: 13.5 vs. 6.0 min, p < 0.001). Higher ovality index of the ostium was seen in patients with ≥4 freezes in inferior PVs [IPVs; 0.95 (0.78–1.05) vs. 0.49 (0.21–0.83), p = 0.047]. During a median of 23.5 months of follow-up, the atrial arrhythmias-free survival after the procedure was comparable between CBA and RFA (p = 0.729).Conclusion: The second-generation CBA is an efficient and safe alternative for RFA in AF patients with COIPV. Anatomical characteristics of COIPV bring the challenge to the procedure performance of RFA and CBA.

The predictive role of early recurrences of atrial arrhythmias after pulmonary vein cryoballoon ablation. Is blanking period an outdated concept? Insights from 12-month continuous cardiac monitoring

BackgroundEarly recurrences of atrial arrhythmias (ERAA) after atrial fibrillation (AF) catheter ablation do not predict procedural failure. A well-demarcated homogeneous lesion delivered by cryoballoon is less arrhythmogenic, and the recommended three-months blanking period may not refer to cryoballoon ablation (CBA).ObjectiveWe aimed to evaluate the predictive role of ERAA after second-generation CBA using an implantable loop recorder.MethodsThis prospective observational study enrolled 100 patients (58 males, median age 58) with paroxysmal/persistent AF undergoing pulmonary vein (PV) CBA using second-generation cryoballoon with simultaneous ECG loop recorder implantation. The duration of follow-up was 12 months, with scheduled visits at 3, 6 and 12 months.Results99 patients from 100 completed the 12-month follow-up period. ERAA occurred in 31.3 % of patients. 83.9 % of patients with ERAA also developed late recurrences. The 12-month freedom from AF in patients with ERAA was significantly lower than in those without ERAA (p < 0.0001). Non-paroxysmal AF and longer arrhythmia history were associated with increased risk of both early (HR 3.27; 95 % CI 1.32–8.08; p = 0.010 and HR 1.0147; 95 % CI 1.008–1.086; p = 0.015, respectively) and late recurrences (HR 3.89; 95 % CI 1.67–9.04; p = 0.002 and HR 1.0142; 95 % CI 1.007–1.078; p = 0.019, respectively) of AF. ERAA were another predictor for procedural failure (HR 15.2; 95 % CI (6.42–35.99; p = 0.019).ConclusionsERAA occurred in the third of the patients after PV second-generation CBA and are strongly associated with procedural failure. Longer duration of AF history and persistent AF are independent predictors of AF’s early and late recurrence.

Association between pericoronary adipose tissue attenuation and outcome after second-generation cryoballoon ablation for atrial fibrillation.

Previous studies reported the association between inflammation and atrial fibrillation (AF). Pericoronary adipose tissue (PCAT) attenuation, PCATA, on cardiac CT angiography (CTA) reflects pericoronary inflammation. We hypothesized that the PCATA predicts AF recurrence after cryoballoon ablation (CBA) for paroxysmal and persistent AF. We studied 364 patients (median age, 65 years) with persistent (n = 41) and paroxysmal (n = 323) AF undergoing successful first-session second-generation CBA with pre-ablation cardiac CTA. Three-vessel (3V)-PCATA was defined as the mean CT attenuation value of PCAT of all three major coronary arteries. Predictors of AF recurrence during follow-up were evaluated. AF recurrence after the 3-month blanking period was detected in 90 patients (24.7%) during the median follow-up of 26 (interquartile range, 19-42) months. AF recurrence was associated with prior stroke and statin use, NT-proBNP and high-sensitivity cardiac troponin-I levels, left ventricular dimension, left atrial volume index (LAVI), 3V-PCATA, and early AF recurrence during the blanking period. On multivariable Cox proportional hazard analysis, prior stroke (hazard ratio [HR], 2.208, 95% confidence interval [CI], 1.166-4.180, p = 0.015), LAVI (HR, 1.030, 95% CI, 1.010-1.051, p = 0.003), 3V-PCATA (HR, 1.034, 95% CI, 1.001-1.069, p = 0.046), and early AF recurrence (HR, 2.858, 95% CI, 1.855-4.405, p < 0.001) remained statistically significant. Pre-ablation CTA-derived 3V-PCATA, representing pericoronary inflammation, was an independent predictor of recurrence after first-session AF ablation using a second-generation cryoballoon. Assessment of 3V-PCATA may identify patients at high risk of AF recurrence after CBA for AF.

Second-generation cryoballoon versus contact force radiofrequency ablation for atrial fibrillation: an updated meta-analysis of evidence from randomized controlled trials

Catheter ablation has been recommended for patients with symptomatic atrial fibrillation (AF), with pulmonary vein isolation being the cornerstone of the ablation procedure. Newly developed technologies, such as cryoballoon ablation with a second-generation cryoballoon (CB2) and the contact force radiofrequency (CF-RF) ablation, have been introduced in recent years to overcome the shortcomings of the widely used RF ablation approach. However, high-quality results comparing CB2 and CF-RF remain controversial. Thus, we conducted this meta-analysis to assess the efficacy and safety between CB2 and CF-RF using evidence from randomized controlled trials (RCTs). Databases including Embase, PubMed, the Cochrane Library, and ClinicalTrials.gov were systematically searched from their date of inception to January 2021. Only RCTs that met the inclusion criteria were included for analysis. The primary outcome of interest was freedom from atrial tachyarrhythmia (AT) during follow-up. Secondary outcomes included procedure-related complications, procedure time and fluoroscopy time. Six RCTs with a total of 987 patients were finally enrolled. No significant differences were found between CB2 and CF-RF in terms of freedom from AT (relative risk [RR] = 1.03, 95% confidence interval [CI] 0.92–1.14, p = 0.616) or total procedural-related complications (RR = 1.25, 95% CI 0.69–2.27, p = 0.457). CB2 treatment was associated with a significantly higher risk of phrenic nerve palsy (PNP) than CF-RF (RR = 4.93, 95% CI 1.12–21.73, p = 0.035). The occurrences of pericardial effusion/tamponade and vascular complications were comparable between the CB2 and CF-RF treatments (RR = 0.41, p = 0.398; RR = 0.82, p = 0.632). In addition, CB2 treatment had a significantly shorter procedure time than CF-RF (weighted mean difference [WMD] = − 20.75 min, 95% CI − 25.44 ~ − 16.05 min, P < 0.001), whereas no difference was found in terms of fluoroscopy time (WMD = 4.63 min, p = 0.179). CB2 and CF-RF treatment are comparable for AF patients regarding freedom from AT and procedure-related complications. Compared to CF-RF, CB2 treatment was associated with a shorter procedure time but a higher incidence of PNP. Further large-scale studies are warranted to compare these two techniques and provide an up-to-date recommendation.

Safety and Efficacy Using the Second-Generation Cryoballoon in Patients With Atrial Fibrillation and a Common Ostium of Inferior Pulmonary Veins.

Background: Common ostium of inferior pulmonary veins (COIPV) is a kind of pulmonary vein variation. The safety and efficacy of COIPV isolation using the second-generation cryoballoon (CB) ablation remain unknown.Methods: A total of 10 patients with COIPV from a consecutive series of 1,751 patients with atrial fibrillation (AF) were included. Pulmonary vein isolation (PVI) was performed using the second-generation CB.Results: The prevalence of a COIPV was 0.57% in this study. PVI was achieved in all pulmonary veins (PVs) without the need for a touch-up. A segmental freeze strategy was applied for each inferior PV, respectively. The mean number of freeze cycles of inferior PVs was 1.4 ± 0.5 for the left inferior pulmonary vein (LIPV), and 2.0 ± 0.9 for the right inferior pulmonary vein (RIPV). Pulmonary vein potential (PVP) of RIPV could not be monitored in real-time in three cases. Eight of 10 patients (80%) were free from atrial arrhythmias without the use of antiarrhythmic drugs during a follow-up period of 23.6 ± 12.9 months. No procedure-related complications occurred in any of the 10 patients.Conclusions: Common ostium of inferior pulmonary veins is a rare but challenging PV variant. PVI with this unusual anatomic variation using the second-generation 28-mm CB is effective and safe.