Feasibility and safety of left atrial posterior wall isolation with a new Cryoballoon technology in patients with persistent atrial fibrillation

Cryoballoon Ablation With the POLARx FIT or the Arctic Front Advance Pro for Paroxysmal Atrial Fibrillation: A Health Economic Analysis

Background: Pulmonary vein isolation (PVI) is the main ablation strategy for the treatment of paroxysmal atrial fibrillation. Different technologies are available for PVI, including various cryoballoon catheters (CB-A). Compared with the Arctic Front Advance Pro™, the novel POLARx FIT™ CB-A might reduce costs for atrial fibrillation ablation. Objective: The aim of this study is to perform a health economic evaluation of two cryoballoon systems for PVI procedures. Methods: All patients undergoing their first PVI procedure with POLARx FIT™ CB-A or the Arctic Front Advance Pro™ CB-A were prospectively enrolled. The health economic analysis was performed on the index hospitalization and procedure. The primary safety endpoint included procedure-related adverse events within the index hospitalization. A decision tree model was built to estimate downstream costs. Results: A total of 80 patients with paroxysmal atrial fibrillation undergoing PVI were analyzed, with 40 patients in each arm. Compared with the Arctic Front Advance Pro™ CB-A, POLARx FIT™ CB-A showed a lower procedure time, left-atrium dwell time, and fluoroscopy time. The complication rate was low (6.3%) and included 3 reversible phrenic nerve palsies in the POLARx FIT™ CB-A group vs 2 in the Arctic Front Advance Pro™ CB-A group. Compared with the Arctic Front Advance Pro, the POLARx FIT™ CB-A was associated with lower procedural costs (€2069.7 ± €165.2 vs €2239.5 ±  €366.0; P =.009). Conclusion: The POLARx FIT™ CB-A was associated with a shorter procedure time, translating into lower procedural costs, compared with the Arctic Front Advance Pro. Complications were rare and comparable between the two technologies.

Thermal and Non-Thermal Energies for Atrial Fibrillation Ablation

The cornerstone of ablative therapy for atrial fibrillation (AF) is pulmonary vein isolation (PVI). Whether PVI should be added with additional lesions in persistent atrial fibrillation (PerAF) or for any post-ablative recurrent AF is a matter of debate. Whatever the ablative strategy, it must determine the choice of energy source to achieve the most durable lesion sets with the least likelihood of complications. Radiofrequency (RF) is the most studied thermal ablation technique. It can be combined with high-density electroanatomic mapping and can be used for both pulmonary and extrapulmonary atrial ablation. Cryoenergy is at least as effective as radiofrequency for PVI; it is rapid, relatively safe, and has a steep learning curve. Therefore, it has been proposed as a first-line approach for PVI-only procedures. More recently, a non-thermal technique based on the application of pulsed direct current (Pulsed Field Ablation-PFA) has been introduced. PFA causes cell death by opening cell membrane pores (electroporation) without a significant increase in tissue temperature. It is fast and does not alter the extracellular matrix as thermal techniques do, although it ends up causing long-lasting, transmural lesions. Most importantly, it is relatively selective on cardiac myocytes and therefore potentially safer than thermal techniques. Some PFA systems can be combined with electroanatomic mapping systems. However, as of now, it appears that these ablation technologies should be considered complementary rather than alternative for a number of practical and theoretical reasons.

Comparative Study of Arctic Front Advance Pro and POLARx Cryoballoons for Linear Ablation of the Left Atrial Roof

BACKGROUND

The effectiveness of cryoballoon ablation (CBA) of the left atrial (LA) roof in addition to pulmonary vein isolation (PVI) using a novel cryoballoon catheter, POLARx, remains unclear.

METHODS

This study compared the efficacy of LA roof line ablation and PVI using POLARx (Boston Scientific) or AFA-Pro (Medtronic) in 100 patients with persistent atrial fibrillation. The right superior pulmonary vein (PV) anchoring and raise-up techniques were consistently used for LA roof line ablation, and rapid right ventricular pacing was applied if the cryoballoon temperature did not reach -40°C.

RESULTS

Complete conduction block at the LA roof could be obtained in all patients with POLARx and in 98.0% of patients with AFA-Pro. Rapid right ventricular pacing was needed in 64.0% of patients with AFA-Pro and in no patients with POLARx. During LA roof line ablation, the nadir cryoballoon temperature was significantly lower with POLARx than with AFA-Pro (right: -54.2°C ± 4.4°C vs. -46.0°C ± 5.4°C; central: -56.8°C ± 4.4°C vs. -45.7°C ± 4.8°C; left: -56.1°C ± 4.3°C vs. -46.1°C ± 5.7°C), and the cryoballoon temperature reached -40°C earlier with POLARx than with AFA-Pro (right: 30.8 ± 7.4 s vs. 74.1 ± 37.7 s; central: 28.2 ± 5.2 s vs. 62.9 ± 30.9 s; left: 29.8 ± 5.8 s vs. 69.6 ± 40.7 s).

CONCLUSION

The nadir cryoballoon temperature with POLARx was approximately 10°C lower than with AFA-Pro, consistently dropping below -40°C during LA roof line CBA. Thus, a complete conduction block of the LA roof line can be easily accomplished using right superior PV anchoring and the raise-up techniques without the need for rapid right ventricular pacing with POLARx.

Novel vs established cryoballoon ablation system for atrial fibrillation: A systematic review and meta-analysis

Background

Recently, a novel cryoballoon ablation system (POLARx) for the treatment of atrial fibrillation has been introduced.

Objective

We aimed at systematically reviewing the efficacy and safety of the POLARx compared with the ArcticFront system.

Methods

Structured systematic database search for articles published between 2021 and 2024 reporting the efficacy and/or safety of the POLARx system for atrial fibrillation ablation. The co-primary endpoints were the long-term efficacy and safety of the POLARx system.

Results

Of the 24 studies with 5364 patients (weighted mean age 62.4 years) included, 15 compared the POLARx system (1746 patients) with the ArcticFront system (2282 patients). Despite significantly lower temperatures at isolation (POLARx -46.3 °C, ArcticFront -31.6 °C, P < .01) and nadir temperatures (POLARx -56.5 °C, ArcticFront -47.8 °C, P < .01), the POLARx system did not show a better acute (98.9% and 99.2% successfully ablated patients and 99.5% and 99.8% successfully ablated pulmonary veins in the POLARx and ArcticFront groups, respectively) or long-term (after a weighted mean follow-up of 12.6 months, the success rate was 69.5% with POLARx and 60.2% with ArcticFront, P = .98) efficacy. While most complications were similar between the POLARx and ArcticFront groups, the incidence of phrenic nerve palsies in the pooled cohorts (all POLARx vs all ArcticFront control patients) differed (2.7% vs 1.6% in the POLARx vs ArcticFront groups; odds ratio 1.79, 95% confidence interval 1.14-2.83, P = .01).

Conclusion

The novel POLARx system provided similar efficiency and acute/long-term efficacy but showed a higher incidence of phrenic nerve palsies compared with the ArcticFront system.

Pentaspline catheter or cryoballoon for pulmonary vein plus posterior wall isolation in persistent atrial fibrillation: 1-Year outcomes

BACKGROUND

Left atrial posterior wall isolation (LAPWI) plus pulmonary vein isolation (PVI) can be performed with radiofrequency ablation, cryoballoon ablation (CB-A), or, recently, pulsed field ablation (PFA).

OBJECTIVE

The aims of this study were to evaluate efficacy and safety of the pentaspline PFA catheter for PVI + LAPWI in patients with persistent AF undergoing an index ablation procedure and to compare 1-year outcomes of PVI + LAPWI with PFA vs CB-A.

METHODS

All consecutive patients undergoing an index ablation for persistent atrial fibrillation (AF) at Universitair Ziekenhuis Brussel, Belgium, between 2021 and 2023 were retrospectively screened. Inclusion criteria were persistent AF diagnosis following current guidelines, first AF ablation procedure with PVI + LAPWI using the CB-A or the pentaspline PFA catheter, and 1-year follow-up completed.

RESULTS

A total of 160 patients were included (80 with CB-A and 80 with the pentaspline PFA catheter). PVI + LAPWI was performed with success in 160 (100%) patients, and isolation was confirmed at postprocedure high-density mapping in all. Compared with CB-A, PFA was associated with shorter skin-to-skin procedure time, shorter left atrium dwell time, and shorter fluoroscopy time. At survival analysis, freedom from recurrent atrial tachyarrhythmias at 1-year follow-up was similar between the CB-A and PFA groups (76.2% vs 78.8%; log-rank P = .63).

CONCLUSION

In patients with persistent AF undergoing an index catheter ablation, the pentaspline PFA catheter is safe and effective for PVI + LAPWI. Outcomes after pentaspline PFA catheter ablation at 1 year are favorable and similar to those with the CB-A catheter.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society (HRS), the Asia Pacific HRS, and the Latin American HRS.

2024 European Heart Rhythm Association/Heart Rhythm Society/Asia Pacific Heart Rhythm Society/Latin American Heart Rhythm Society expert consensus statement on catheter and surgical ablation of atrial fibrillation

In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society, the Asia Pacific Heart Rhythm Society, and the Latin American Heart Rhythm Society .

Posterior wall isolation via a multi-electrode radiofrequency balloon catheter: feasibility, technical considerations, endoscopic findings and comparison with cryoballoon technologies

BACKGROUND

Posterior wall (PW) isolation is an important adjunctive ablation target in patients with non-paroxysmal atrial fibrillation (AF). Traditionally performed with point-by-point radiofrequency (RF) ablation, PW isolation has also been performed with different cryoballoon technologies. We aimed at assessing the feasibility of PW isolation with the novel RF balloon catheter Heliostar™ (Biosense Webster, CA, USA).

METHODS

We prospectively enrolled 32 consecutive patients with persistent AF scheduled for first-time ablation with the Heliostar™ device. Procedural data were compared with those from 96 consecutive persistent AF patients undergoing pulmonary vein (PV) plus PW isolation with a cryoballoon device. The ratio RF balloon/cryoballoon was 1:3 for each operator involved in the study, aiming at avoiding any imbalance related to different experience.

RESULTS

Single-shot PV isolation was documented in a significantly higher number of cases with the RF balloon technology compared to cryoballoon ablation (89.8% vs. 81.0%; p = 0.02, respectively). PW isolation was achieved with a similar number of balloon applications between the two groups (11 ± 4 with the RF balloon versus 11 ± 2 with the cryoballoon; p = 0.16), but in a significantly shorter time among RF balloon patients (228 ± 72 s versus 1274 ± 277 s with cryoballoon; p < 0.001). Primary safety endpoint occurred in none of the RF balloon patients versus 5 (5.2%) patients in the cryoballoon group (p = 0.33). Primary efficacy endpoint was achieved in all (100%) RF balloon patients versus 93 (96.9%) cryoballoon ones (p = 0.57). Oesophageal endoscopy did not show any signs of thermal lesions in RF balloon patients with luminal temperature rise.

CONCLUSIONS

RF balloon-based PW isolation was safe and promoted shorter procedure times compared to similar cryoballoon-based ablation procedures.

Coronary artery disease in atrial fibrillation ablation: impact on arrhythmic outcomes

AIMS

Catheter ablation (CA) is an established treatment for atrial fibrillation (AF). A computed tomography (CT) may be performed before ablation to evaluate the anatomy of pulmonary veins. The aim of this study is to investigate the prevalence of patients with coronary artery disease (CAD) detected by cardiac CT scan pre-ablation and to evaluate the impact of CAD and revascularization on outcomes after AF ablation.

METHODS AND RESULTS

All consecutive patients with AF diagnosis, hospitalized at Universitair Ziekenhuis Brussel, Belgium, between 2015 and 2019, were prospectively screened for enrolment in the study. Inclusion criteria were (i) AF diagnosis, (ii) first procedure of AF ablation with cryoballoon CA, and (iii) contrast CT scan performed pre-ablation. A total of 576 consecutive patients were prospectively included and analysed in this study. At CT scan, 122 patients (21.2%) were diagnosed with CAD, of whom 41 patients (7.1%) with critical CAD. At survival analysis, critical CAD at CT scan was a predictor of atrial tachyarrhythmia (AT) recurrence during the follow-up, only in Cox univariate analysis [hazard ratio (HR) = 1.79] but was not an independent predictor in Cox multivariate analysis. At Cox multivariate analysis, independent predictors of AT recurrence were as follows: persistent AF (HR = 2.93) and left atrium volume index (HR = 1.04).

CONCLUSION

In patients undergoing CT scan before AF ablation, critical CAD was diagnosed in 7.1% of patients. Coronary artery disease and revascularization were not independent predictors of recurrence; thus, in this patient population, AF ablation should not be denied and can be performed together with CAD treatment.

Hybrid atrial fibrillation ablation: long-term outcomes from a single-centre 10-year experience

AIMS

Hybrid atrial fibrillation (AF) ablation is a promising approach in non-paroxysmal AF. The aim of this study is to assess the long-term outcomes of hybrid ablation in a large cohort of patients after both an initial and as a redo procedure.

METHODS AND RESULTS

All consecutive patients undergoing hybrid AF ablation at UZ Brussel from 2010 to 2020 were retrospectively evaluated. Hybrid AF ablation was performed in a one-step procedure: (i) thoracoscopic ablation followed by (ii) endocardial mapping and eventual ablation. All patients received PVI and posterior wall isolation. Additional lesions were performed based on clinical indication and physician judgement. Primary endpoint was freedom from atrial tachyarrhythmias (ATas). A total of 120 consecutive patients were included, 85 patients (70.8%) underwent hybrid AF ablation as first procedure (non-paroxysmal AF 100%), 20 patients (16.7%) as second procedure (non-paroxysmal AF 30%), and 15 patients (12.5%) as third procedure (non-paroxysmal AF 33.3%). After a mean follow-up of 62.3 months ± 20.3, a total of 63 patients (52.5%) experienced ATas recurrence. Complications occurred in 12.5% of patients. There was no difference in ATas between patients undergoing hybrid as first vs. redo procedure (P = 0.53). Left atrial volume index and recurrence during blanking period were independent predictors of ATas recurrence.

CONCLUSION

In a large cohort of patients undergoing hybrid AF ablation, the survival from ATas recurrence was 47.5% at ≈5 years follow-up. There was no difference in clinical outcomes between patients undergoing hybrid AF ablation as first procedure or as a redo.

Ultra-high-resolution assessment of lesion extension after cryoballoon ablation for pulmonary vein isolation

INTRODUCTION

Unrecognized incomplete pulmonary vein (PV) isolation during the index procedure, can be a major cause of clinical recurrences of atrial fibrillation (AF) after cryoballoon (CB) ablation. We aimed to characterize the extension of the lesions produced by CB ablation and to assess the value of using an ultra-high resolution electroanatomic mapping (UHDM) system to detect incomplete CB lesions.

MATERIALS AND METHODS

Twenty-nine consecutive patients from the CHARISMA registry undergoing AF ablation at four Italian centers were prospectively evaluated. The Rhythmia™ mapping system and the Orion™ (Boston Scientific) mapping catheter were used to systematically map the left atrium and PVs before and after cryoablation.

RESULTS

A total of 116 PVs were targeted and isolated. Quantitative assessment of the lesions revealed a significant reduction of the antral surface area of the PV, resulting in an ablated area of 5.7 ± 0.7 cm2 and 5.1 ± 0.8 cm2 for the left PV pair and right PV pair, respectively (p = 0.0068). The mean posterior wall (PW) area was 22.9 ± 2 cm2 and, following PV isolation, 44.8 ± 6% of the PW area was ablated. After CB ablation, complete isolation of each PV was documented by the POLARMap™ catheter in all patients. By contrast, confirmatory UHDM and the Lumipoint™ tool unveiled PV signals in 1 out of 114 of the PVs (0.9%). Over 30-day follow-up, no major procedure-related adverse events were reported. After a mean follow-up of 333 days, 89.7% of patients were free from arrhythmia recurrence.

CONCLUSION

The lesion extension achieved by the new CB ablation system involved the PV antrum, with less than 50% of the PW remaining untouched. The new system, with short tip and circular mapping catheter, failed to achieve PV isolation in only 0.9% of all PVs treated.

CLINICAL TRIAL REGISTRATION

[http://clinicaltrials.gov/], identifier [NCT03793998].

Cryoballoon ablation beyond pulmonary vein isolation in the setting of persistent atrial fibrillation

INTRODUCTION

Catheter ablation has been demonstrated to be a safe and an effective treatment for drug resistant atrial fibrillation (AF); electrical isolation of pulmonary veins (PVI) is the main strategy in paroxysmal AF, since pulmonary vein triggers have a pivotal role in its pathogenesis; non-paroxysmal AF is a complex arrhythmia that results from the interplay of a substrate, namely AF-induced electrical and structural atrial remodeling, and a trigger that can be often found outside pulmonary veins, namely non-pulmonary veins triggers.

AREAS COVERED

The aim of this review is to provide a state-of-the-art overview of non-pulmonary veins triggers with special focus on cryoballoon (CB) catheter ablation.

EXPERT OPINION

Besides PVI, CB catheter ablation of non-pulmonary veins triggers is a novel and promising strategy for non-paroxysmal AF.