Second-generation Cryoballoon Research Articles

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.

Safety and efficacy of the second-generation cryoballoon for left atrial appendage electrical isolation in canines.

Left atrial appendage electrical isolation (LAAEI) has demonstrated a significant enhancement in the success rate of atrial fibrillation (AF) ablation. Nevertheless, concerns persist about the safety of LAAEI, particularly regarding alterations in left atrial appendage (LAA) flow velocity and the potential risks of thrombus. This study aimed to assess the efficacy and safety of LAAEI, investigating changes in LAA flow velocity in canines. The study comprised a total of 10 canines. The LAAEI procedure used by a 23 mm cryoballoon of the second generation was conducted at least 180 s. Intracardiac ultrasonography (ICE) was employed to quantify the velocity flow of the LAA both prior to and following LAAEI. Following a 3-month period, subsequent evaluations were performed to assess the LAA velocity flow and the potential reconnection. Histopathological examination was conducted. Left atrial appendage electrical isolation was effectively accomplished in all canines, resulting in a 100% acute success rate (10/10). The flow velocity in the LAA showed a notable reduction during LAAEI as compared with the values before the ablation procedure (53.12 ± 5.89 vs. 42.01 ± 9.22 cm/s, P = 0.007). After the follow-up, reconnection was observed in four canines, leading to a success rate of LAAEI of 60% (6/10). The flow velocity in the LAA was consistently lower (53.12 ± 5.89 vs. 44.33 ± 10.49 cm/s, P = 0.006), and no blood clot development was observed. The histopathological study indicated that there was consistent and complete injury to the LAA, affecting all layers of its wall. The injured tissue was subsequently replaced by fibrous tissue. The feasibility of using cryoballoon ablation for LAAEI was confirmed in canines, leading to a significant reduction of LAA flow velocity after ablation. Some restoration of LAA flow velocity after ablation may be linked to the passive movement of the LAA and potential reconnecting. However, this conclusion is limited to animal study; more clinical data are needed to further illustrate the safety and accessibility of LAAEI in humans.

Early Clinical Outcomes and Advantages of a Novel-Size Adjustable Second-Generation Cryoballoon: A Proof-of-Concept Study.

(1) Background/Objective Balloon-guided catheter ablation (CA) has emerged as an alternative option for atrial fibrillation (AF) management. The recent introduction of a novel-size adjustable second-generation cryoballoon (CB) system offers innovations, but clinical outcomes remain unexplored. This study aims to assess the acute performance of the POLARx FIT™ CB system in AFCA. (2) Methods: Consecutive patients undergoing AF ablation with the POLARx FIT™ CB system in our center were included. The primary outcome was the rate of 31 mm balloon-size utilization, with secondary outcomes including acute pulmonary vein isolation (PVI) rate, periprocedural complications, and in-hospital AF recurrences. (3) Results: Twenty-four patients with a mean age of 59.5 years, predominantly male (87.5%), and exhibiting paroxysmal AF (91.7%) were enrolled. Procedural characteristics demonstrated a high acute success rate (100% PV isolation) with a favorable safety profile. Notably, the 31 mm CB configuration was utilized in 51% of applications, showcasing its adaptability in challenging anatomies. No major complications occurred, with two patients experiencing in-hospital self-limiting AF recurrences. (4) Conclusions: This study represents the first comprehensive assessment of the POLARx FIT™ CB system in AF ablation. While acknowledging the study's limitations, this novel CB emerges as a promising tool, warranting further exploration in larger studies with extended follow-up periods.

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.

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).

Left atrial appendage volume is an independent predictor of atrial arrhythmia recurrence following cryoballoon pulmonary vein isolation in persistent atrial fibrillation.

Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation in persistent AF (persAF), and cryoballoon PVI emerged as an initial ablation strategy. Symptomatic atrial arrhythmia recurrence following successful PVI in persAF is observed more frequently than in paroxysmal AF. Predictors for arrhythmia recurrence following cryoballoon PVI for persAF are not well described, and the role of left atrial appendage (LAA) anatomy is uncertain. Patients with symptomatic persAF and pre-procedural cardiac computed tomography angiography (CCTA) images undergoing initial second-generation cryoballoon (CBG2) were enrolled. Left atrial (LA), pulmonary vein (PV) and LAA anatomical data were assessed. Clinical outcome and predictors for atrial arrhythmia recurrence were evaluated by univariate and multivariate regression analysis. From May 2012 to September 2016, 488 consecutive persAF patients underwent CBG2-PVI. CCTA with sufficient quality for measurements was available in 196 (60.4%) patients. Mean age was 65.7 ± 9.5 years. Freedom from arrhythmia was 58.2% after a median follow-up of 19 (13; 29) months. No major complications occurred. Independent predictors for arrhythmia recurrence were LAA volume (HR 1.082; 95% CI, 1.032 to 1.134; p = 0.001) and mitral regurgitation ≥ grade 2 (HR, 2.49; 95% CI 1.207 to 5.126; p = 0.013). LA volumes ≥110.35 ml [sensitivity: 0.81, specificity: 0.40, area under the curve (AUC) = 0.62] and LAA volumes ≥9.75 ml (sensitivity: 0.56, specificity 0.70, AUC = 0.64) were associated with recurrence. LAA-morphology, classified as chicken-wing (21.9%), windsock (52.6%), cactus (10.2%) and cauliflower (15.3%), did not predict outcome (log-rank, p = 0.832). LAA volume and mitral regurgitation were independent predictors for arrhythmia recurrence following cryoballoon ablation in persAF. LA volume was less predictive and correlated with LAA volume. LAA morphology did not predict the clinical outcome. To improve outcomes in persAF ablation, further studies should focus on treatment strategies for persAF patients with large LAA and mitral regurgitation.

Pulsed field versus cryoballoon ablation of atrial fibrillation: A comparison of efficacy and safety in a 400 patient cohort

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): Boris Schmidt, KR Julian Chun and Stefano Bordignon received speaking honoraria from Medtronic and Boston Scientific Background The cryoballoon (CB) is one of the most commonly used single shot devices for pulmonary vein isolation in patients with atrial fibrillation (AF). Pulsed field ablation (PFA) is a new non-thermal, tissue selective approach for pulmonary vein isolation. Purpose We sought to compare procedural safety and efficacy of these single shot ablation techniques. Methods Consecutive AF patients (paroxysmal / persistent AF) who underwent CB based pulmonary vein isolation (PVI) between November 2020 and February 2022 were enrolled and compared with patients who underwent PFA ablation in the same time period. Patients that underwent ablation beyond PVI (except for cavo-tricuspid isthmus ablation) were excluded. CB PVI was performed using the second-generation CB (CB 28 mm) with 240 sec based freeze protocol and bonus freeze delivery in case of time-to-isolation (TTI) >75 sec. PFA was performed using the Farawave catheter, using the 31 or 35 mm device. All procedures were performed under deep sedation. Results Data from 400 consecutive patients were collected. Most baseline characteristics like age (CB: 67,5 ± 15,3; PFA: 68,4 ± 11; p=0,49), BMI (CB: 28,6 ± 6,3; PFA: 27,9 ± 5,6; p=0,27) and gender (male) (CB: 54%; PFA: 59%; p=0,31) were comparable between the two groups. All PVIs were successfully completed. In 98% (196) of patients in the CB group and 100% (200) in the PFA group, PVI was performed using solely CB or PFA respectively, meaning additional touch up ablation was only needed in 4 CB patients (2%; p=0,044) and 4 veins. Procedure time was significantly shorter in the PFA group (CB: 53 ± 15,3 minutes; PFA: 36,8 ± 13,5 minutes; p<0,001), whereas no difference in fluoroscopy time (CB: 8,1 ± 4,4 minutes; PFA: 7,8 ± 3,3 minutes; p=0,2) was observed. The rate of concomitant CTI-ablation was equal in both groups (CB: 1,5%; PFA: 1,5%; p=1,0). Complication rate was 3,5% with PFA and 6,5% in CB (p=0,17), a difference mostly driven by persistent phrenic nerve palsies (CB: 1,5%; PFA: 0%; p=0,08). All patients are out of the blanking period. There were 80 recurrences in blanking time (CB: 41; PFA: 39; p=0,8). In CB 19,5% of blanking time recurrences were atrial tachycardias compared to 35,9% in PFA (p=0,1). The average time to blanking recurrence was 14,1 ± 21,5 days in CB and 20,5 ± 23,2 in PFA (p=0,2). In total, there were 7 repeat procedures (4 in CB and 3 in PFA; p=0,7) during blanking time due to arrhythmias, despite of antiarrhythmic drugs and/or cardioversion. At the time of this analysis, the first hundred patients in each group reached one-year follow-up. Recurrence free survival after one year for patients with PAF was 82,6% in CB and 80,0% in PFA. In patients with persistent AF it was 70,8% in CB and 67,8% in PFA. Conclusion Cryoballoon and pulsed field ablation are both highly effective and safe techniques for PVI. PFA had a shorter procedure time, whereas the one year follow up was similar for both techniques.

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.

Best Practice Guide for Cryoballoon Ablation in Atrial Fibrillation: The Compilation Experience of More than 1000 Procedures

Nowadays, the cryoballoon (CB) constitutes an established alternative to radio frequency (RF) ablation for pulmonary vein isolation (PVI), which offers the possibility to isolate the PVs with a single application. Since the introduction of the second-generation CB, we prospectively collected our data to optimize the procedure on >1000 consecutive patients who underwent CB PVI performed in our center. It is expected that subsequent guidelines will suggest first-line PVI through CB in patients with paroxysmal AF with a class I indication. Indeed, in the long-term follow-up (36 months) of the EARLY-AF trial, CB had a lower incidence of persistent atrial fibrillation episodes compared to the anti-arrhythmic drugs group. We now review the current best practices in an effort to drive consistent outcomes and minimize complications. PV isolation through CB is the most studied single-shot technique for atrial fibrillation ablation, having shown the potential to alter the natural history of the arrhythmia. Several procedural tips and tricks can improve procedural flow and effectiveness. In the present article we provided not only technical details but measurable biophysical parameters that can reliably guide the operator into achieving the best outcome for his patients.

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

Ahead of Print article withdrawn by publisher.

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.

Predictors of AF recurrence in patients with paroxysmal AF undergoing catheter ablation: new predictors coming?

Abstract Introduction Recurrence of atrial fibrillation (AF) after catheter ablation (CA) is estimated to be between 20% and 45% and the prediction of recurrence AF in patients (pts) with paroxysmal AF undergoing CA remains challenging. Purpose To determine the clinical and procedural predictors of recurrence AF after CA in pts with paroxysmal AF. Methods Single-centre retrospective study that included all pts with paroxysmal AF who underwent AF CA between 2017 and 2019. Ablation procedures included radiofrequency and second-generation cryoballoon CA. All pts underwent cardiac computed tomography prior the procedure. AF recurrence was defined as any recurrence of AF, atrial flutter or atrial tachycardia &amp;gt;30 seconds (recorded in 12-lead electrocardiogram or Holter) after 90 days of CA. The independent association between clinical and procedural variables and AF recurrence was evaluated with Cox regression analysis. Results We included 351 pts, 63,5% male and with a mean age of 57,1±11,4 years. CHADSVASCscore ≥2 points were present in 43,7% of the pts, median duration of AF prior the intervention was 3 years (IQR 1–6) and most pts were treated with some antiarrhythmic drug at the time of CA (56,9%). Overall, median follow-up was 27 months (IQR 19–39). AF recurrence was present in 96 pts (27,4%), on average, 15,2±10,4 months after CA. Univariate logistic regression identified female gender, thyroid disease, left atrium (LA) enlargement (defined as LA indexed volume &amp;gt;34 mL/m2 or LA diameter &amp;gt;38mm for female or &amp;gt;40mm for male), coronary calcium score &amp;gt;100, epicardial adipose tissue volume, number of previous electric cardioversions, treatment with antiarrhythmic drugs prior CA and the extent of CA (only pulmonary vein isolation (PVI) or PVI and ablation of other lesions) as predictors of recurrence AF after CA in pts with paroxysmal AF (p&amp;lt;0,05 for all). Cox regression analysis identified female gender (OR 1,615, 95% CI 1,005–2,597; p=0,008), LA enlargement (OR 2,084, 95% CI 1,207–3,596; p=0,008) and coronary calcium score &amp;gt;100 (OR 1,958, 95% CI 1,133–3,385; p=0,016) as independent predictors of AF recurrence. Conclusions In our cohort, AF recurrence was significantly higher in pts with LA enlargement, with coronary calcium score &amp;gt;100 and female gender pts. Funding Acknowledgement Type of funding sources: None.

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).

A novel alternating second-generation cryoballoon or contact-force guided radiofrequency catheter ablation strategy for redo-ablation in patients with recurrent atrial fibrillation: a single-center experience.

Pulmonary vein (PV) reconnection after radiofrequency (RFC) or cryoballoon (CB) pulmonary vein isolation (PVI) is common. We report a single-center experience of 156 patients who underwent a redo procedure-ablation strategy for recurrent atrial fibrillation (AF) in a reverse sequence after a failed index RFC or CB PVI. A total of 60 patients after index CB PVI underwent RFC-redo ablation (CB-RFC redo), and 96 patients after index RFC PVI underwent CB-redo ablation (RFC-CB redo). During the redo procedure, the proportion of patients with PV reconnection was lower after index CB PVI procedure compared with the proportion of patients after index RFC PVI (88.3% versus 98.9%, p = 0.01). Additionally, a mean number of 1.50 ± 0.8 PVs/patient were reconnected after index CB PVI, compared with 3.36 ± 0.9 PVs/patient after index RFC PVI (p = 0.001). Patients after index RFC PVI frequently presented with ≥ 3 reconnected PVs, compared with index CB PVI (70.8% vs 10%, p < 0.001). At a 2-year follow-up, 43 patients (27.6%) developed recurrence after redo ablation, with a similar AF-free outcome (CB-RFC redo:73.3% vs RFC-CB redo: 71.9%, p = 0.873). In the multivariate analysis, persistent AF (HR = 2.107, 95% CI: 1.085-4.091, p = 0.028) and early AF recurrence after the initial ablation (HR = 2.431, 95% CI: 1.279-4.618, p = 0.007) were independent predictors of AF recurrence. The extent and distribution of PV reconnections were different after index RFC and CB PVI procedures. Alternating CB or RFC ablation technique strategy is effective with a similar long-term outcome, and it may be an appropriate option for repeated AF ablation.

Pulmonary vein size is associated with reconnection following cryoballoon ablation of atrial fibrillation.

The second-generation cryoballoon (CB) has proven to be a highly effective ablative strategy in patients with symptomatic atrial fibrillation (AF). This study sought to investigate the anatomical characteristics of pulmonary veins (PVs) and the relationship between their size, ovality, and late reconnections in a large cohort of patients undergoing repeat ablation for recurrence of atrial arrhythmias. A total of 152 consecutive patients (98 males, 64.5%; mean age 64.9 ± 9.6years) underwent a repeat ablation for recurrent atrial tachyarrhythmias after a median time of 6.5months [IQR 11] from the index CB ablation. All repeat ablations were performed using a 3-dimensional electro-anatomical mapping system. Among all 593 PVs, 134 (22.6%) showed a late PV reconnection in 95 patients (0.88 per patient), at the time of repeat ablation procedure. There was a significant difference in ovality between left- and right-sided PVs (p < 0.001). Greater diameters of left superior PV, left inferior PV, and right inferior PV ostia (both maximum and minimum) and higher index ovality were significantly associated with late PV reconnection. The rate of late PV reconnection after CB ablation was low (0.88 PVs/patient). Left-sided PVs were more oval than septal PVs. Larger PV dimensions and higher ovality index were significantly associated with reconnections in all PVs except for RSPV.

Stand-alone Focal Impulse and Rotor Modulation (FIRM) ablation versus second-generation cryoballoon pulmonary vein isolation for paroxysmal atrial fibrillation.

Focal Impulse and Rotor Modulation (FIRM) guided catheter ablation aiming at stable rotors has been investigated as a treatment option in patients with atrial fibrillation (AF). The objective of this study was to compare the safety and efficacy of FIRM-guided ablation with second-generation cryoballoon pulmonary vein isolation (CB2-PVI) in paroxysmal AF. Consecutive patients (n = 22, mean age 60 ± 11 years, 59.1% of males) who were treated with a stand-alone FIRM-guided ablation were included in this retrospective single-center study. Procedural data and arrhythmia-free survival at 12 months were compared with n = 86 consecutive patients (mean age 62 ± 13 years, 62.4% of males) who received de-novo CB2-PVI. Median procedure duration was significantly longer in the FIRM group than in the CB2-PVI group (152 [IQR 120-176] minutes vs. 122 [110-145] minutes; p = .031). One patient (1.2%) in the CB2-PVI group and five patients (22.7%) in the FIRM group had vascular access complications. Atrial tachyarrhythmias recurred in 15 patients in the FIRM group and 11 in the CB2-PVI group. Kaplan-Meier estimation of single-procedure arrhythmia-free survival at 12 months was 25% (95% confidence interval [CI] 6%-44%) in the FIRM group and 87% (95% CI 78%-96%) in the CB2-PVI group (p < .001). Repeat ablations were performed in 14/20 (70.0%) patients in the FIRM group and in 12/85 (14.1%) in the CB2-PVI group (p < .001). De novo ablation of AF using FIRM-guided AF ablation results in shorter arrhythmia-free survival after 12 months compared to CB2-PVI and a need for repeat ablation in the majority of patients to achieve stable sinus rhythm.

The mitral inflow E/A ratio before the procedure may predict late recurrence after pulmonary vein isolation using second-generation cryoballoon

Abstract Funding Acknowledgements Type of funding sources: None. Background The left ventricular (LV) diastolic dysfunction (DD) increases the risk of atrial fibrillation (AF) development. Some studies investigated whether a relationship between DD and late recurrence after catheter ablation for AF, but they found conflictory results. Such studies had relatively short follow-up duration and they did not have a standard ablation protocol. Some patients were taken to PVI only, while additional linear lesions in localizations such as the left atrial (LA) roof, LA isthmus, and cavotricuspid isthmus were added in others. Purpose The mitral inflow E/A ratio is a simple and practical method commonly used to evaluate LV DD. We aimed to investigate whether the E/A ratio before the procedure was predictive for late recurrence in patients with AF undergoing pulmonary vein isolation (PVI) with cryoballoon (CB). Methods A total of 100 patients undergoing AF ablation for the first time using second-generation CB were included. Only patients with paroxysmal AF and sinus rhythm the day before the procedure, and with pre-procedural pro-B natriuretic peptide levels within normal limits were included. The patients with and without late recurrence were compared in terms of basal characteristics and procedural features. Any atrial tachyarrhythmia episode longer than 30 s after the blanking period was defined as late recurrence. Results The patients [age: 58.0 (50.2-62.0) years, 53 female] were followed up for a median of 44.5 (14.2-62.7) months and late recurrence developed in 25 patients. Female gender (72.0% vs 46.7%), hypertension (72.0% vs 48.0%), and the frequency of early recurrence (20.0% vs 4.0%) were found to be higher in patients with late recurrence than in those without it (p =0.028, 0.037 and 0.022, respectively). The CHA2DS2-Vasc score was higher [2.0 (1.0-3.0) vs 1.0 (0-2.0)], AF duration was longer (27.8 ± 9.4 vs 22.0 ± 8.4 months) and the E/A ratio was lower [0.5 (0.4-1.2) vs 1.4 (0.6-1.7)] in patients with late recurrence than in those without it (p=0.014, 0.006 and 0.001, respectively) (Figure 1). The groups were similar in terms of precedural features. A multivariate analysis showed that female gender (HR: 4.46, 95%CI: 1.24-15.97, p=0.021), early recurrence (HR: 10.22, 95% CI: 2.49-41.99, p=0.001), and E/A ratio (HR: 0.25, 95%CI: 0.11-0.57, p=0.001) were independent predictors for late recurrence (Figure 2). Receiver operating characteristic analysis showed that the optimal cut-off level of the E/A ratio was 0.84. Any ATa free survival rate was significantly lower in patients with E/A ratio &amp;lt;0.84 than in those with ≥0.84 (56.1% vs 88.1%, log-rank p&amp;lt;0.001). Conclusions Female gender, early recurrence, and E/A ratio are independent predictors of late recurrence in patients with AF undergoing PVI using second-generation CB. Measuring the E/A ratio in patients with sinus rhythm before AF ablation may help to predict future recurrences.

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.