Posterior wall ablation by pulsed-field ablation: procedural safety, efficacy, and findings on redo procedures

Extrapulmonary Vein Areas with Pulsed Field Ablation: Is the Transition Completed?

Pulsed field ablation (PFA) is an innovative technology for the ablation of atrial fibrillation (AF), characterized by its ability to create tissue-selective lesions while minimizing collateral damage to surrounding structures. Isolation of the pulmonary veins (PVs) remains the cornerstone of AF ablation; however, recent evidence underscores the significance of extra-PV triggers, such as those from the posterior wall of the left atrium, the superior vena cava, the coronary sinus, and the left atrial appendage. While preliminary data suggest that PFA may enhance safety outcomes compared to traditional thermal techniques, further studies needed to validate its efficacy in non-PV areas.

[Guideline to safe and effective atrial fibrillation ablation with pulsed-field ablation using the pentaspline PFA system as an example]

Atrial fibrillation ablation is an established procedure for the treatment of atrial fibrillation, in which Pulsed Field Ablation (PFA) is a novel method alongside radiofrequency and cryoablation. The article explains the technical basics of PFA, describes different types of catheters and gives detailed instructions on how to perform the procedure, from patient selection to sedation strategies and imaging. Important safety aspects and possible complications are also covered. Finally, the further development of PFA technology for the treatment of other arrhythmias and integration into 3D mapping systems is discussed. This work is part of a series of articles on further training in special rhythmology.

Pulsed Field Ablation for Persistent Atrial Fibrillation: 1-Year Results of ADVANTAGE AF

BACKGROUND

Pulsed field ablation (PFA) has gained prominence for pulmonary vein isolation (PVI) to treat atrial fibrillation, but there are limited outcome data on PFA to treat persistent atrial fibrillation (PerAF).

OBJECTIVES

This study sought to determine the safety and efficacy of PVI + posterior wall ablation (PWA) with PFA in PerAF.

METHODS

ADVANTAGE AF (A Prospective Single Arm Open Label Study of the FARAPULSE Pulsed Field Ablation System in Subjects with Persistent Atrial Fibrillation) is a prospective, single-arm, multicenter pivotal investigational device exemption study of PerAF patients undergoing PVI+PWA with the pentaspline PFA catheter. One-year follow-up included 24-hour Holter monitoring at 6 and 12 months and twice monthly and symptomatic transtelephonic monitoring. The primary safety endpoint was incidence of predefined adverse events. The primary effectiveness endpoint included acute success and postblanking 1-year freedom from atrial tachyarrhythmia recurrence (>30 seconds), redo ablation, cardioversion, or antiarrhythmic drug escalation. Endpoint analysis used Kaplan-Meier methodology with 97.5% 1-sided confidence limits compared with a 12% safety and 40% effectiveness goals, with 85% power.

RESULTS

PFA in 339 patients (260 treatment and 79 roll-in) resulted in 99.7% success for both PVI and PWA. The primary safety endpoint was 2.3% (5.1% upper confidence limit), including 1 with pericarditis, 1 with myocardial infarction, and 4 with pulmonary edema; no tamponade, stroke, pulmonary vein stenosis, or esophageal fistula occurred. Primary effectiveness was 63.5% (57.3% lower confidence limit) at 1 year, with 8.5% patients having a single, isolated atrial fibrillation recurrence. Freedom from symptomatic atrial fibrillation was 85.3%; efficacy varied by operator experience.

CONCLUSIONS

ADVANTAGE AF, the first large prospective study of PFA to treat PerAF using a strategy of PVI and posterior wall isolation, revealed favorable safety and effectiveness outcomes. (A Prospective Single Arm Open Label Study of the FARAPULSE Pulsed Field Ablation System in Subjects with Persistent Atrial Fibrillation [ADVANTAGE AF]; NCT05443594).

Pulsed-field ablation versus radiofrequency or cryoballoon thermal ablation in atrial fibrillation: a systematic review and meta-analysis

This review investigated efficacy and safety of pulsed-field ablation (PFA) in comparison with radiofrequency ablation (RFA), cryoballoon ablation (CBA), or both combined. The Odds ratio (OR) and mean difference (MD) with 95% confidence interval (95% CI) were computed. PFA allowed shorter procedure (MD -44.27 minutes, 95% CI: -63.61; -24.93) and left atrium (LA) dwell (MD -32.71 minutes (95% CI: -58.64; -6.78) times, but with longer fluoroscopy time than RFA (MD 8.54 minutes, 95% CI: 4.03; 13.04). Post-procedural complications rate was lower with PFA than CBA (OR 0.53, 95% CI: 0.35, 0.80). Atrial arrhythmias recurrence rate within one year of follow-up was lower with PFA than RFA (OR 0.68, 95% CI; 0.53; 0.87) and CBA (OR 0.69, 95% CI: 0.48; 0.97). PFA allowed shorter procedure and LA dwell times, as well as lower atrial arrhythmia recurrence than RFA and lower post-procedural complications and atrial arrhythmias recurrence rates than CBA.

Durability of Ultra-Low Temperature Cryoablation Lesions in Atrial Fibrillation: Insights From Repeat Ablation Procedures

BACKGROUND

Ultra-low temperature cryoablation (ULTC) is a technique designed to rapidly cool cardiac tissue to extremely low temperatures, enabling the creation of ablation lesions for the treatment of atrial fibrillation (AF). Prior studies have demonstrated low rates of arrhythmia recurrence, but little is known about ablation lesion durability.

METHODS

Patients undergoing repeat ablation were selected from the CryoCure2 (NCT02839304) and iCLAS PMCF(NCT05416086) studies. Baseline patient and ULTC procedure characteristics were evaluated. During repeat ablation, ULTC ablation lesions were assessed for electrical block, including segment-based assessment of pulmonary vein (PV) ablation lesions. Arrhythmia outcomes after repeat ablation were evaluated.

RESULTS

Twenty-five patients were included in the cohort: Age 68 ± 7 years, male 68%, persistent AF 68%, LAVI 42 ± 24 mL/m2. During index procedure, ULTC was used to target the PVs in all patients, the left atrium posterior wall (LAPW) in 15 patients, the lateral mitral isthmus (LMI) in five patients and the cavotricuspid isthmus (CTI) in two patients. At repeat ablation, PV reconnection was observed in 21/25 patients (55/100 PVs reconnected), and reconnection occurred most often in the anterior segments of the left PVs. The LAPW lesion was incomplete in 4/15 patients, the LMI in 3/5 and the CTI in 1/2. After repeat ablation, 10/25 patients had arrhythmia recurrence.

CONCLUSION

Reconnection of ablation targets during repeat ablation for arrhythmia recurrence following ULTC occurred at rates comparable to those observed with conventional thermal ablation modalities. The anterior side of the left PVs appears to be reconnected most often.

Left Atrial Substrate Modification for Long-Standing Persistent Atrial Fibrillation and Left Atrial Macro- or Micro-Reentrant Tachycardia Using a Single-Shot Pulsed Field Ablation System-A Case Series

Background: Pulsed field ablation [PFA] is a novel ablation technique for pulmonary vein isolation [PVI] in patients with paroxysmal and persistent atrial fibrillation. However, data for the efficacy and safety of PFA for left atrial substrate modification using a single shot PFA system, in patients with long-standing persistent atrial fibrillation [AF] and left atrial macro- as well as micro-reentrant atrial tachycardia [LAMRT], are scarce. Here, we provide a small, single-center case series regarding the efficacy and safety of left atrial substrate modification using a single-shot PFA system. Methods: Nine patients with long-standing persistent AF and LAMRT underwent redo-PVI and left atrial substrate modification using a single-shot PFA system. Patients were subsequently followed up for 1 year. Results: The median age was 64 years [IQR 55.5-75], with 44% of the participants being female. The median time since the first diagnosis of AF was 7 years [IQR 4-15.5]. After re-PVI, posterior wall isolation was performed in five patients, roof isolation in six patients, and anterior wall ablation between the superior mitral annulus and the right superior pulmonary vein [RSPV] in five patients. In two patients, cavotricuspid isthmus ablation was additionally performed to treat typical atrial flutter. The acute procedural success rate was 100%, with all LAMRTs and typical flutters successfully terminating by ablation. At 1-year follow-up, four patients [44%] experienced a recurrence of any atrial arrhythmia. Median time to recurrence was 164 days [138-212.8]. Importantly, no acute or chronic complications were observed. Conclusions: In this small, single-center case series, left atrial substrate modification for long-standing persistent AF and AT using a single-shot PFA system was safe and showed an excellent acute success rate.

Catheter Ablation of Atrial Fibrillation: Technique and Future Perspectives

Atrial fibrillation is the most common sustained cardiac arrhythmia with a significant impact on quality of life in terms of symptoms and reduction of functional status. Also, it is associated with an increased risk of mortality, stroke, and peripheral embolism. Catheter ablation for atrial fibrillation has become a well-established treatment, improving arrhythmia outcomes without increasing the risk of serious adverse events compared to antiarrhythmic drug therapy. The field has undergone significant advancements in recent years, yet pulmonary vein isolation continues to be the cornerstone of any atrial fibrillation ablation procedure. The purpose of this review is to provide an overview of the current techniques, emerging technologies, and future directions.

Posterior left atrial wall isolation for treatment of persistent atrial fibrillation during first-time catheter ablation: An updated systematic review and meta-analysis

BACKGROUND

Although catheter ablation (CA) by mean of pulmonary vein isolation (PVI) is nowadays the mainstay treatment for atrial fibrillation (AF), its success-rate in persistent AF remains suboptimal. Results from studies evaluating whether adding posterior wall isolation (PWI) to PVI can increase the success-rate of CA in persistent AF have yielded conflicting data. The aim of this meta-analysis was to assess whether PWI plus PVI might be beneficial in patients with persistent AF.

METHODS

Electronic databases were searched for randomized control trials (RCTs) and observational studies that compared clinical outcomes between patients with persistent AF who underwent PVI with or without PWI.

RESULTS

Fifteen studies, including a total of 3072 patients, were considered (1533 treated with PVI and 1539 with PWI + PVI). Comparing patients treated with or without PWI, no statistically significant difference was found in the risk of any atrial tachyarrhythmias recurrence after CA (RR 0.83; 95 % CI 0.66-1.03). The analyses detected a statistically significant reduction in the risk of AF in patients treated with PWI (RR 0.63; 95 % CI 0.48-0.84) balanced by a trend towards an increased risk of atrial flutter/atrial tachycardia (RR 1.51; 95 % CI 0.92-2.49). No statistically significant differences were identified in the risk of major procedural complications (RR 0.94; 95 % CI 0.50-1.78).

CONCLUSIONS

According to our updated meta-analysis, the addition of PWI to PVI was not associated with a reduction of atrial arrhythmia recurrences. A reduction of the risk of AF recurrence and a trend towards an increased risk of atrial flutter/atrial tachycardia were identified.

Pulsed-Field vs Thermal Catheter Ablation of Atrial Fibrillation in Patients With Hypertrophic Cardiomyopathy

BACKGROUND

Pulsed-field ablation (PFA) may be beneficial for the treatment of atrial fibrillation (AF) in patients with hypertrophic cardiomyopathy (HCM).

OBJECTIVES

The goal of this study was to compare the safety and efficacy of PFA and thermal ablation in patients with HCM and AF.

METHODS

From 2016 to 2024, patients with HCM undergoing a first AF ablation using PFA or thermal ablation (cryoballoon or radiofrequency) were retrospectively included from 3 French and Swiss centers. Freedom from atrial arrhythmia (AA) recurrence at the 12-month follow-up was assessed.

RESULTS

Overall, 109 patients (median age 60 years; 68% male; 43% paroxysmal AF) with HCM underwent PFA (n = 58) or thermal ablation (n = 51) of AF. In addition to pulmonary vein (PV) isolation, extra-PV ablation was performed in 62% of PFA cases and in 18% of thermal cases. PFA was associated with shorter median procedure times than thermal ablation (81 minutes [Q1-Q3: 60-110 minutes] vs 132 minutes [Q1-Q3: 75-190 minutes]; P < 0.0001) and with less postprocedural heart failure (n = 0 vs n = 4; P = 0.03). Freedom from AA recurrence was 57% (95% CI: 46%-67%) after 12 months. PFA was associated with less AA recurrence than thermal ablation (adjusted HR: 0.46; 95% CI: 0.23-0.91; P = 0.03). Extra-PV ablation was associated with more sustained AA recurrence with thermal ablation (HR: 3.07; 95% CI: 1.21-7.82; P = 0.02) but not with PFA (HR: 1.07; 95% CI: 0.35-3.27; P = 0.91).

CONCLUSIONS

In patients with HCM and AF, PFA seems to be associated with better safety and efficacy outcomes than thermal ablation.

Pulsed field ablation in atrial fibrillation ablation: where are we and where are we going?

Pulsed field ablation (PFA) offers a novel approach to treating atrial fibrillation, demonstrating promising efficacy and safety. Unlike traditional thermal ablation techniques like radiofrequency or cryoablation, PFA uses non-thermal irreversible electroporation to selectively target myocardial tissue, minimizing damage to surrounding structures such as the oesophagus, phrenic nerve, and coronary arteries. Initial studies indicate that PFA is effective in achieving durable pulmonary vein isolation and posterior wall isolation, with a low incidence of serious complications. However, more long-term clinical data are needed to further confirm its efficacy.

Catheter ablation using pulsed-field energy: Advantages and limitations compared with conventional energy

Atrial fibrillation (AF) poses significant risks of heart failure and stroke, emphasizing effective treatment. Catheter ablation using thermal energy sources, such as radiofrequency or cryoballoon ablation, has shown greater success in maintaining sinus rhythm compared with drug therapy. However, thermal ablation (TA) is associated with serious complications, such as atrial-esophageal fistula, phrenic nerve palsy, and pulmonary vein stenosis. Pulsed-field ablation (PFA) is an emerging ablation energy source that uses electroporation to selectively target cardiac tissue while sparing adjacent structures such as nerves and blood vessels. Two randomized controlled trials have demonstrated that PFA is comparable to TA in both efficacy and safety at a 1-year follow-up and had shorter procedure times. A review of six meta-analyses consistently showed shorter procedural times for PFA across all studies. Additionally, three out of the four recent studies with large samples reported lower recurrence rates with PFA. Regarding complication rates, four out of four studies showed lower incidences of phrenic nerve injury with PFA, and two out of three studies reported lower rates of esophageal injury with PFA. However, four out of four studies indicated higher incidences of cardiac tamponade with PFA, highlighting the need for caution among early-career operators. Furthermore, careful monitoring is required considering the possible unforeseen complications specific to PFA and the lack of long-term follow-up data. Despite these concerns, PFA shows promise as a safer, more effective, and efficient alternative to TA for AF, particularly as operator experience and device technology continue to advance.

A tailored substrate-based approach using focal pulsed field catheter ablation in patients with atrial fibrillation and advanced atrial substrate: Procedural data and 6-month success rates

BACKGROUND

Focal pulsed field ablation (F-PFA) integrated in electroanatomic mapping systems allows tailored lesion sets in patients with atrial fibrillation (AF).

OBJECTIVE

We aimed to determine feasibility, safety, and 6-month outcome of F-PFA for a tailored substrate-based catheter ablation approach in patients with AF and advanced atrial substrate.

METHODS

Consecutive patients with AF and advanced atrial substrate treated by an F-PFA system (CardioFocus) through contact force-sensing catheters integrated in electroanatomic mapping systems were prospectively enrolled. The tailored substrate-based catheter ablation approach included isolation of all pulmonary veins with wide area circumferential ablation, posterior wall isolation, mitral anterior line, and cavotricuspid isthmus ablation, according to substrate. At 6 months, feasibility, arrhythmia recurrence, and safety were evaluated.

RESULTS

In 83 patients (33% female; indexed left atrial volume, 44 ± 15 mL/m2; 80% persistent AF or atrial flutter [AFl]; 57% redo procedures), successful de novo pulmonary vein isolation was performed in 36 patients and pulmonary vein reisolation in 30 patients. Mitral anterior line was performed in 19 patients with atypical AFl or anterior low-voltage areas; posterior wall isolation was performed in 38 patients with low-voltage areas or evoked delayed electrograms during premature atrial extrastimuli; and cavotricuspid isthmus ablation was performed in 24 patients with typical AFl. Median procedural and fluoroscopy times were 115 and 7 minutes, respectively. No complications occurred. At 6 months, arrhythmia recurred in 30 of 83 patients (21 AF; 9 atypical AFl).

CONCLUSION

Tailored substrate-based F-PFA in patients with AF and advanced atrial substrate is safe and effective. Acute procedural success was 100% with 64% freedom from arrhythmias after 6 months.

Atrial Fibrillation Ablation During Hospitalization for Acute Heart Failure: Feasibility and Role of Pulsed Field Ablation

INTRODUCTION

Atrial fibrillation (AF) can cause or aggravate heart failure (HF). Catheter ablation (CA) is an effective treatment for AF. This study focused on the feasibility and outcomes of emergent AF ablation performed during hospitalization for acute HF.

METHODS AND RESULTS

We retrospectively investigated patients who underwent emergent CA for AF during hospitalization for acute HF in 2018-2024. Arrhythmia recurrence was the primary endpoint. The combination of arrhythmia recurrence, HF hospitalization, and all-cause death was the secondary endpoint. Patients were censored 1 year after the index procedure. We included 46 patients, 35% females, with median age of 67 [interquartile rage: 61, 72] years and left ventricular ejection fraction (LVEF) of 25 [23, 28]%. Thermal CA was performed in 14 patients, and pulsed field ablation (PFA) in 32 patients. Procedure time was significantly shorter with PFA compared to thermal CA (77 [57, 91] vs. 166 [142, 200] minutes, p < 0.001). Fluoroscopy time was longer with PFA (9.5 [7.6, 12.0] vs. 3.9 [2.9, 6.0] minutes, p < 0.001), with a borderline trend towards higher radiation dose (75 [53, 170] vs. 50 [30, 94] μGy.m2, p = 0.056). Extrapulmonary ablation was frequent (86% and 84% for thermal CA and PFA, p > 0.9). The estimated freedom from the primary endpoint was 79% after PFA and 64% after thermal CA (p = 0.44). The estimated freedom from the secondary endpoint was 76% after PFA and 57% after thermal CA (p = 0.43). LVEF improved by 24% ± 2% (p < 0.001) in patients with the first manifestation of HF and by 14% ± 4% (p = .004) in patients with decompensated HF diagnosed earlier.

CONCLUSIONS

Emergent CA of AF during acute HF hospitalization is safe and associated with improved LVEF and good clinical outcomes. In the PFA era, the rate of these procedures is progressively increasing as they are readily available and easy to perform compared to thermal ablation.

Pulsed-field ablation of atrial fibrillation with a pentaspline catheter across National Health Service England centres

INTRODUCTION

Pulsed-field ablation (PFA) is a novel modality for pulmonary vein isolation in patients with atrial fibrillation (AF). We describe the initial uptake and experience of PFA using a pentaspline catheter across selected National Health Service England (NHSE) centres.

METHODS

Data collected by NHSE Specialised Services Development Programme regarding AF ablation procedures using a single-shot, pentaspline, multielectrode PFA catheter (FARAWAVE, Boston Scientific) between June 2022 and August 2024 were aggregated and analysed to examine procedural metrics, acute efficacy and safety outcomes over 3-month follow-up.

RESULTS

1034 procedures were submitted. The patients were 32.1% female, mean age 63.8±10.7 years, 53.1% paroxysmal AF and 89.7% first-time AF ablation. Procedures were performed by 48 consultant operators at nine NHSE centres, with a mean of 115 procedures per centre (range 25-264). 93.7% of procedures were performed under general anaesthesia. Median skin-to-skin procedure time was 74 min (IQR 55-96 min) and fluoroscopy time 20 min (IQR 15-27 min). Electroanatomical mapping was used in 15.3%. In first-time ablation cases, acute isolation of all pulmonary veins was achieved in 99.5% of patients. Left atrial (LA) posterior wall ablation using the PFA catheter was performed in 11.0% of cases; additional LA radiofrequency ablation was performed in 0.6%. The major and minor acute procedural complication rates were, respectively, 1.3% and 3.1%, with no reports of periprocedural death or atrio-oesophageal fistula. 63.8% of patients were discharged on the day of procedure. Follow-up data were available for 870 procedures (84.1%). In the 3 months following ablation, hospitalisation for arrhythmia occurred in 3.2%, with 0.9% rehospitalised for procedural-related complications.

CONCLUSION

In this real-world, nationwide registry of a pentaspline PFA catheter, efficacy, safety and efficiency outcomes were comparable to those from previous PFA studies in patients with AF.

Pulsed Field Ablation as First-Line Therapy for Atrial Fibrillation: A Substudy of the EU-PORIA Registry

BACKGROUND

Recent studies have demonstrated the benefit of early ablation in preventing the progression of atrial fibrillation (AF). Clinical practice has reflected this shift in AF management and no longer requires patients to fail antiarrhythmic drugs (AADs) before receiving ablation. However, there is limited evidence on outcomes with pulsed field ablation (PFA) as a first-line therapy. Examination of real-world data may shed light on clinical practices and the effectiveness of PFA with and without a prior history of AAD usage.

METHODS

European Real World Outcomes with Pulsed Field Ablation is an all-comer AF registry enrolling consecutive patients treated with the pentaspline PFA catheter at 7 high-volume centers in Europe. This subanalysis evaluates patients with a history of class I/III AAD use versus those with no documented history of class I/III AAD use (first-line patients). Patients with incomplete AAD history, long-standing persistent AF, and those undergoing a repeat ablation procedure were excluded. Patients were treated and followed based on institutional standard of care. Any episode of atrial tachycardia or AF lasting longer than 30 s was considered an arrhythmia recurrence.

RESULTS

Of 1233 patients enrolled in European real world outcomes with pulsed field ablation, 1091 met the inclusion criteria (mean age, 66 years; 40% females; and persistent AF, 36%). Pulmonary vein isolation-only was used in 90% of the patients, and 10% received extra-PV ablation. Ablation as the first-line approach was chosen in 589 patients, and 502 patients had prior class I/III AAD use. In the first-line PFA group, paroxysmal AF was more frequent (68% versus 59%; P<0.001), and pulmonary vein isolation-only was more frequent (93% versus 86%; P<0.001). At 1-year follow-up, freedom from AF/atrial tachycardia recurrence was similar in the ablation-first versus the ablation after failed AAD group (78% versus 74%, respectively; P=0.076).

CONCLUSION

In this large real-world PFA registry, freedom from AF/atrial tachycardia recurrence after 1 year was similar in patients undergoing PFA as a first-line treatment and those with prior failed AAD therapy.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT05823818.

Catheter ablation for atrial fibrillation: indications and future perspective

Recent advances in techniques, technologies and proven superiority over anti-arrhythmic drugs have made catheter ablation the cornerstone of management for atrial fibrillation (AF), which has shown a steady increase in prevalence in the ageing population worldwide. The aim of therapeutic interventions is to achieve stable sinus rhythm that would improve the quality of life and reduce the risk of AF-associated complications. Pulmonary veins (PVs) were first described as the source of initiation of ectopic triggers driving AF, which led to the establishment of PV isolation (PVI) as the most widely practiced procedure to treat AF. Antral PVI is still recognized as the stand-alone ablation strategy for newly diagnosed paroxysmal AF (PAF). However, in non-PAF patients, PVI seems to be inadequate and several adjunctive strategies, including ablation of left atrial posterior wall and non-PV triggers, AF mapping and ablation of rotors and drivers, ethanol infusion of vein of Marshall and renal denervation, etc. have been reported with mixed results. Recent trials have also documented the benefits of early rhythm control in preventing cardiovascular events in addition to slowing the progression of PAF to more persistent forms. Similarly, very late relapse of the arrhythmia after successful PVI has drawn attention to the critical role of non-PV triggers and highlighted their relevance as potential ablation targets during repeat procedures. Ablation technology is also under constant evolution with the introduction of non-thermal energy sources and new tools to create durable lesions. This review summarizes the indications, advancements, and future perspective of AF ablation.

Pulsed Field Ablation in Atrial Fibrillation: Initial Experience of the Efficacy and Safety in Pulmonary Vein Isolation and Beyond

Regional differences in pulsed field ablation (PFA) adoption for pulmonary vein isolation (PVI) with additional posterior wall ablation (PWA) in Asia remains unknown. We hereby report our experience on the safety and efficacy of PFA in AF ablation. Consecutive AF patients who underwent PFA from September 2022 to January 2024 were included. The primary efficacy endpoint was freedom from atrial arrhythmia recurrence after a 90-day blanking period at 12 months. Safety endpoints included 30 days of all-cause death, cardiac tamponade, stroke, myocardial infarction, and heart failure hospitalization. One hundred and one (72.3% males, 79.2% pAF) patients underwent PFA for AF. Thirty-one (30.7%) had structural heart disease with mean LVEF of 57.4 ± 8.1% and CHA2DS2-VASc score of 1.4 ± 1.3. Twenty-nine (28.7%) underwent additional PWA (PVI + PWA) using PFA. PWA was acutely successful in all patients. Patients who underwent PWA were more likely to have persistent AF and require general anesthesia and electroanatomic mapping (all p < 0.05). Total PFA applications for PVI, LA dwell time, procedural time, and fluoroscopy time were similar between the PVI-only and PVI + PWA groups (all p > 0.05). The 1-year atrial arrhythmia recurrence rates were 10% for pAF and 21% for the persistent AF group. The primary efficacy endpoint was not significantly different between the PVI-only and PVI+PWA groups (12-month KM estimates 90.3% [95% CI, 83.3-97.3] and 82.8% [95% CI, 68.1-97.4], respectively). There were no complications related to PFA use. PFA can be safely, effectively, and efficiently adopted for AF ablation. Additional PWA, if pursued, had similar procedural metrics to the PVI-only strategy without increased complications.

Anatomical Treatment Strategies for Persistent Atrial Fibrillation with Ethanol Infusion within the Vein of Marshall-Current Challenges and Future Directions

Currently, pulmonary vein isolation (PVI) is the gold standard in catheter ablation for atrial fibrillation (AF). However, PVI alone may be insufficient in the management of persistent AF, and complementary methods are being explored. One such method takes an anatomical approach-improving both its success rate and lesion durability may lead to improved treatment outcomes. An additional approach complementary to the anatomical one is also attracting attention, one that focuses on epicardial conduction. This involves ethanol ablation of the vein of Marshall (VOM) and can be very effective in blocking epicardial conduction related to Marshall structure; it is becoming incorporated into standard treatment. However, the pitfall of this "Marshall-PLAN", a method that combines an anatomical approach with ethanol infusion within the VOM (Et-VOM), is that Et-VOM and other line creations are not always successfully completed. This has led to cases of AF and/or atrial tachycardia (AT) recurrence even after completing this lesion set. Investigating effective adjunctive methods will enable us to complete the lesion set with the aim to lower the rates of recurrence of AF and/or AT in the future.

Left atrial posterior wall isolation in addition to pulmonary vein isolation using a pentaspline catheter in pulsed-field ablation for atrial fibrillation: A systematic review and meta-analysis

BACKGROUND

Persistent atrial fibrillation (AF) may require extensive ablation strategies. Left atrial posterior wall isolation (LAPWI) might address potential substrates for recurrence during pulsed-field ablation (PFA).

OBJECTIVE

This meta-analysis aimed to investigate the feasibility and effectiveness of LAPWI in addition to pulmonary vein isolation (PVI) using a pentaspline catheter in PFA for AF.

METHODS

Comprehensive search was conducted using PubMed, SCOPUS, ScienceDirect, and EuropePMC for studies reporting LAPWI+PVI using a pentaspline catheter in PFA ablation for AF. The primary outcome was atrial tachyarrhythmia (ATa) recurrence, defined as AF/atrial flutter/atrial tachycardia after blanking period.

RESULTS

There were 882 patients from 7 studies. The success rate of LAPWI was 100% using mean/median of 16 to 20 added PFA applications with no reported acute left atrial posterior wall reconnection and esophageal complications. In mean follow-up of 240 ± 91 days, ATa recurrence was 21% (95% CI 13%-29%; I2 = 84.8%) in the LAPWI+PVI group. Meta-regression analysis showed that age, left ventricular ejection fraction, and repeat procedure did not significantly influence ATa recurrence (P > .05). Each 1-mm increase in left atrial diameter, increases the chance of ATa recurrence by 6% (R2 = 100%, P < .001, I2 = 0%). Meta-analysis showed no difference in terms of ATa recurrence among LAPWI+PVI patients compared with those without LAPWI (odds ratio 0.78, 95% confidence interval 0.50-1.21, P = .27; I2 = 0%, P = .86). Procedure time and fluoroscopy time did not significantly differ (P > .05).

CONCLUSION

LAPWI using a pentaspline catheter during PFA was feasible and did not prolong the procedure/fluoroscopy but did not reduce ATa recurrence. LAPWI may be considered during PFA, although the benefit is uncertain.

Convergent ablation for persistent atrial fibrillation: A UK multicentre perspective

Atrial fibrillation (AF) is the most common sustained arrhythmia worldwide and remains a major cause of morbidity and mortality. Unfortunately, a significant proportion of patients have persistent AF, for which conventional catheter ablation is less effective. However, convergent ablation has emerged in recent years as a hybrid treatment targeting both the epicardium and endocardium in a multidisciplinary joint cardiothoracic and electrophysiology procedure, with promising efficacy outcomes in recent studies. This treatment is increasingly being performed in the United Kingdom. This review article discusses the rationale and evidence behind convergent ablation, along with factors that need to be considered when setting up a successful ablation service.

High-Power Short-Duration Posterior Wall Isolation in Addition to Pulmonary Vein Isolation in Persistent Atrial Fibrillation Ablation Using the New TactiFlex™ Ablation Catheter

BACKGROUND

The TactiFlex™ ablation catheter, Sensor Enabled™ (Abbott, Minneapolis, MN, USA), is an open-irrigation radiofrequency (RF) ablation catheter with flexible tip technology. This catheter delivers high-power short-duration (HPSD) RF ablations and has been adopted for atrial fibrillation (AF) ablation. HPSD is well-established not only in pulmonary vein isolation (PVI) but also when targeting extra-pulmonary vein (PV) targets. This study aims to determine the safety, effectiveness, and acute outcomes of PVI plus posterior wall isolation (PWI) in patients with persistent atrial fibrillation (Pe-AF) using HPSD and the TactiFlex™ ablation catheter.

METHODS

Consecutive patients who underwent the ablation of Pe-AF in our centre between February 2023 and February 2024 were prospectively enrolled in the study. All patients underwent PVI plus PWI using TactiFlex™ and the HPSD strategy. The RF parameters were 50 W on all the PV segments and the roof, and within the posterior wall (PW). Left atrial mapping was performed with the EnSite X mapping system and the high-density multipolar Advisor HD Grid, Sensor Enabled™ mapping catheter. We compared the procedural data using HPSD with TactiFlex™ (n = 52) vs. a historical cohort of patients who underwent PVI plus PWI using HPSD settings and the TactiCath ablation catheter (n = 84).

RESULTS

Fifty-two consecutive patients were included in the study. PVI and PWI were achieved in all patients in the TactiFlex™ group. First-pass PVI was achieved in 97.9% of PVs (n = 195/199). PWI was obtained in all cases by delivering extensive RF lesions within the PW. There were no significant differences compared to the TactiCath group: first-pass PVI was achieved in 96.3% of PVs (n = 319/331). Adenosine administration revealed PV reconnection in 5.7% of patients, and two reconnections of the PW were documented. Procedure and RF time were significantly shorter in the TactiFlex™ group compared to the TactiCath group, 73.1 ± 12.6 vs. 98.5 ± 16.3 min, and 11.3 ± 1.5 vs. 23.5 ± 3.6 min, respectively, p < 0.001. The fluoroscopy time was comparable between both groups. No intraprocedural and periprocedural complications related to the ablation catheter were observed. Patients had an implantable loop recorder before discharge. At the 6-month follow-up, 76.8% of patients remained free from atrial arrhythmia, with no significant differences between groups.

CONCLUSIONS

HPSD PVI plus PWI using the TactiFlex™ ablation catheter is effective and safe. Compared to a control group, the use of TactiFlex™ to perform HPSD PVI plus PWI is associated with a similar effectiveness but with a significantly shorter procedural and RF time.

Sequential Isolation of Persistent Left Superior Vena Cava and Right Superior Vena Cava Using Pulsed-field Ablation with a Pentaspline Catheter for Recurrent Persistent Atrial Fibrillation

Pulsed-field ablation (PFA) is a novel technology for atrial fibrillation (AF) ablation that can deliver energy precisely with a lower risk of damage to the surrounding organs. Persistent left superior vena cava (PLSVC) is a congenital variant that can act as a driver of AF, and its isolation may be required in recurrent persistent AF. We describe a case where PFA was used for isolation of the right superior vena cava, PLSVC, and posterior wall of the left atrium.

Safety and effectiveness of additional left atrial posterior wall ablation using pulsed field ablation for persistent and long-standing persistent atrial fibrillation patients

INTRODUCTION

The unique safety profile of pulsed field ablation (PFA) has made pulmonary vein isolation (PVI) + left atrial posterior wall (LAPW) ablation promising for treating persistent atrial fibrillation (PerAF). The goal of this study was to assess long-term freedom from atrial fibrillation, atrial flutter, and atrial tachycardia (AF/AFL/AT), as well as the safety and feasibility of LAPW PFA using multipolar, pentaspline Farawave catheter.

METHODS

Retrospective observational study at a single institution. Data for 94 patients were collected from a prespecified intraprocedural registry. The long-term AF/AFL/AT recurrence assessment was based on an analysis of medical history; 24-h Holter ECGs at 3, 6, and 12 months postablation; and 12-lead ECGs recorded during symptomatic episodes or visits.

RESULTS

Half of the patients had ls-PerAF, and half had a history of catheter ablation-mostly RF PVI. The acute ablation success rate was 100%, and the primary safety outcome was observed in 2 patients. Fifty patients experienced AF/AFL/AT recurrence (54.3%). An increase in LAPW low-voltage areas and AF classification were associated with arrhythmia recurrence. After a median follow-up of 13 months, the Kaplan‒Meier estimated median time free of AF/AFL/AT after a single procedure was 14.7 months.

CONCLUSION

PFA PVI + PWA had the best outcome in perAF patients without extensive LA fibrosis. AF recurrence was paroxysmal in significant part of the cohort. The addition of PWA to PVI using multipolar PFA was safe and did not significantly influence the transpired ablation time.

Pulsed-field vs cryoballoon vs radiofrequency ablation: Outcomes after pulmonary vein isolation in patients with persistent atrial fibrillation

BACKGROUND

Pulsed-field ablation (PFA) has shown promising data in terms of safety and procedural efficiency for pulmonary vein isolation (PVI), with similar long-term outcomes compared to radiofrequency ablation (RFA) and cryoballoon ablation (CBA) in patients with paroxysmal atrial fibrillation (AF).

OBJECTIVE

The purpose of this study was to compare the procedural and long-term outcomes in patients with persistent AF undergoing PVI using PFA, CBA, or RFA.

METHODS

Consecutive patients with persistent AF undergoing first PVI with PFA, CBA, or RFA were included. Patients underwent 7-day Holter electrocardiography at 3, 6, and 12 months postablation. The primary outcome was recurrence of any atrial arrhythmia after a 90-day blanking period. Safety outcomes included the composite of in-hospital major adverse events.

RESULTS

A total of 533 patients with persistent AF underwent PVI using PFA (n = 214, 39%), CBA (n = 190, 36%), or RFA (n = 129, 24%). Procedures with PFA guided by fluoroscopy were shorter than those with CBA (median 60 minutes; interquartile range [IQR] 53-80 minutes vs 84 minutes; IQR 68-101 minutes; P ≤ .001), and procedures with PFA in combination with 3-dimensional electroanatomic mapping were shorter than those with RFA (median 101 minutes; IQR 85-126 minutes vs 171 minutes; IQR 141-204 minutes; P < .001). Acute safety events occurred in 2.3%, 2.6%, and 0.8% in the PFA, CBA, and RFA groups, respectively (P = .545). The 1-year confounder-adjusted estimate for freedom from atrial arrhythmias was 62.1% for CBA, 55.3% for PFA, and 48.3% for RFA (CBA vs PFA: P = .79; CBA vs RFA: P = .009; PFA vs RFA: P = .010).

CONCLUSION

In patients with persistent AF undergoing first PVI, 1-year confounder-adjusted outcomes are better with PFA and CBA than with RFA.

Superior vena cava isolation using a pentaspline pulsed-field ablation catheter: feasibility and safety in patients undergoing atrial fibrillation catheter ablation

AIMS

Superior vena cava (SVC) isolation during atrial fibrillation catheter ablation is limited by the risk of collateral damage to the sinus node and/or the phrenic nerve. Due to its tissue-specificity, we hypothesized the feasibility and safety of pulsed-field ablation (PFA)-based SVC isolation.

METHODS AND RESULTS

One hundred and five consecutive patients undergoing PFA-based AF catheter ablation were prospectively included. After pulmonary vein isolation (±posterior wall isolation and electrical cardioversion), SVC isolation was performed using a standardized workflow. Acute SVC isolation was achieved in 105/105 (100%) patients after 6 ± 1 applications. Transient phrenic nerve stunning occurred in 67/105 (64%) patients but without phrenic nerve palsy at the end of the procedure and at hospital discharge. Transient high-degree sinus node dysfunction occurred in 5/105 (4.7%) patients, with no recurrence at the end of the procedure and until discharge. At the 3-month follow-up visit, no complication occurred.

CONCLUSION

SVC isolation using a pentaspline PFA catheter is feasible and safe.

Feasibility study on atrial fibrillation ablation with pulsed field ablation and concomitant occlusion of the left atrial appendage

AIMS

Atrial fibrillation (AF) ablation and left atrial appendage occlusion (LAAO) are increasingly performed as individual procedures. Pulsed field ablation (PFA) has significantly reduced procedure duration and may be advantageous for the combined approach.

METHODS AND RESULTS

We have launched a programme for simultaneous AF ablation using PFA and LAAO for patients qualifying for both treatments and excluding those with a complex anatomy. We compare procedure duration and fluoroscopy time against individual procedures (either AF ablation or LAAO alone), all performed by the same operators and using consistent technologies. We performed the combined procedure in 10 patients (50% males; median age 70 years) and excluded 2 patients (17%) because of a complex left atrial appendage anatomy. No death, stroke, or major bleeding events, including pericardial effusion, occurred. For single-procedure comparison, 207 AF ablation procedures and 61 LAAO procedures were available. The total median procedure duration was 79 min (range 60-125) for the combined procedure, 71 min (25-241) for individual AF ablation (51 min without and 78 min with 3-dimensional electroanatomic mapping), and 47 min (15-162) for individual LAAO. The respective fluoroscopy times were 21 (15-26), 15 (5-44), and 10 (3-50) min. For the combined procedure, femoral vein access to last PFA application lasted 49 min (34-93) and LAAO added 20 min (15-37).

CONCLUSION

Simultaneous PFA-based AF ablation and LAAO in carefully selected patients is feasible and safe and can be executed within a short overall procedure duration.

Hybrid-Convergent Procedure or Pulsed Field Ablation in Long-Standing Persistent Atrial Fibrillation

BACKGROUND

Hybrid-convergent radiofrequency (RF) ablation targeting pulmonary veins (PVs) and left atrial posterior wall (LAPW) has shown better arrhythmic outcomes than an endocardial-only RF strategy, despite higher rates of complications. Comparisons with extensive pulsed field ablation (PFA) are currently lacking.

OBJECTIVES

This study aimed to compare the efficacy and safety of the hybrid-convergent RF vs PFA of PVs and LAPW in long-standing persistent atrial fibrillation (LSPAF).

METHODS

Ninety-three consecutive LSPAF patients, treated with 2-step hybrid-convergent RF ablation (hybrid group, n = 49) or with PFA of PVs and LAPW (PFA group, n = 44) were enrolled. Primary efficacy endpoint was defined as any atrial tachyarrhythmias (ATA) recurrence after the 3-month blanking period, over a follow-up time of 12 months. Periprocedural adverse events and late complications during follow-up were deemed primary safety outcomes.

RESULTS

The hybrid and PFA groups had similar baseline characteristics; mean age was hybrid 63.8 ± 10.6 years vs PFA 66.0 ± 7.4 years; P = 0.105. PV and LAPW ablation were acutely successful in all patients. Step 1 hybrid-epicardial procedures were longer than PFA (166 [Q1-Q3: 140-205] minutes vs 107.5 [Q1-Q3: 82.5-12] minutes; P < 0.01). At 12-month follow-up, there was no difference in ATA recurrences between groups (hybrid 36.7% vs PFA 40.9%; P = 0.680; log-rank at survival analysis P = 0.539). After adjusting for confounders, a larger left atrial volume and recurrences during the blanking-period were predictors of ATA recurrences after ablation, regardless of procedural technique employed. PFA showed a better safety profile with a lower rate of major periprocedural complications compared with hybrid ablation (12% vs 0%; P = 0.028).

CONCLUSIONS

Hybrid-convergent and PFA share comparable arrhythmic outcomes in LSPAF, but hybrid-convergent ablation carries higher periprocedural risks.

Impact of Posterior Wall Isolation During AF Ablation on the Incidence of Left Atrial Flutter

BACKGROUND

Linear and complex electrogram ablation (LCEA) beyond pulmonary vein isolation (PVI) is associated with an increase in left atrial macro-re-entrant tachycardias (LAMTs). Posterior wall isolation (PWI) is increasingly performed to improve AF ablation outcomes. However, the impact of PWI on the incidence of LAMT is unknown.

OBJECTIVES

The purpose of this study was to establish the incidence of LAMT following PVI alone vs PVI + PWI vs PVI + PWI + LCEA.

METHODS

Consecutive patients undergoing catheter ablation for AF or LAMT post-AF ablation between 2008 and 2022 from 4 electrophysiology centers were reviewed with a minimum follow-up of 12 months.

RESULTS

In total, 5,619 (4,419 index, 1,100 redo) AF ablation procedures were performed in 4,783 patients (mean age 60.9 ± 10.6 years, 70.7% men). Over a mean follow-up of 6.4 ± 3.8 years, 246 procedures for LAMT were performed in 214 patients at a mean of 2.6 ± 0.6 years post-AF ablation. Perimitral (52.8% of patients), roof-dependent (27.1%), PV gap-related (17.3%), and anterior circuits (8.9%) were most common, with 16.4% demonstrating multiple circuits. The incidence of LAMT was significantly higher following PVI + PWI (6.2%) vs PVI alone (3.0%; P < 0.0001) and following PVI + PWI + LCEA vs PVI + PWI (12.5%; P = 0.019). Conduction gaps in previous ablation lines were responsible for LAMT in 28.4% post-PVI alone, 35.3% post-PVI + PWI (P = 0.386), and 81.8% post-PVI + PWI + LCEA (P < 0.005).

CONCLUSIONS

The incidence of LAMT following PVI + PWI is higher than with PVI alone but significantly lower than with more extensive atrial substrate modification. Given a low frequency of LAMT following PWI, empiric mitral isthmus ablation is not justified and may be proarrhythmic.

State-of-the-art pulsed field ablation for cardiac arrhythmias: ongoing evolution and future perspective

Pulsed field ablation (PFA) is an innovative approach in the field of cardiac electrophysiology aimed at treating cardiac arrhythmias. Unlike traditional catheter ablation energies, which use radiofrequency or cryothermal energy to create lesions in the heart, PFA utilizes pulsed electric fields to induce irreversible electroporation, leading to targeted tissue destruction. This state-of-the-art review summarizes biophysical principles and clinical applications of PFA, highlighting its potential advantages over conventional ablation methods. Clinical data of contemporary PFA devices are discussed, which combine predictable procedural outcomes and a reduced risk of thermal collateral damage. Overall, these technological developments have propelled the rapid evolution of contemporary PFA catheters, with future advancements potentially impacting patient care.

Pulsed-field ablation for repeat procedures after failed prior thermal ablation for atrial fibrillation

Background

Pulsed-field ablation (PFA) is a novel nonthermal ablation technology. Its potential value for repeat procedures after unsuccessful thermal ablation for atrial fibrillation has not been assessed.

Objective

The purpose of this study was to summarize our initial experience with patients undergoing repeat procedures using PFA.

Methods

Consecutive patients with arrhythmia recurrences after a prior thermal ablation undergoing a repeat procedure using a multipolar PFA catheter from May 2021 and December 2022 were included. After 3-dimensional electroanatomic mapping, reconnected pulmonary veins (PVs) were reisolated and veins with only ostial isolation wither ablated to widen antral PV isolation. Posterior wall ablation was performed if all PVs were durably isolated or in case of low-voltage areas on the posterior wall at the discretion of the operator. Patients underwent follow-up with 7-day Holter electrocardiography after 3, 6, and 12 months.

Results

A total of 186 patients undergoing a repeat procedure using PFA were included. The median number of previous ablations was 1 (range 1-6). The prior ablation modality was radiofrequency in 129 patients (69.4%), cryoballoon in 51 (27.4%), and epicardial ablation in 6 (3.2%). At the beginning of the procedure, 258 of 744 PVs (35%) showed reconnections. Additional antral ablations were applied in 236 of 486 still isolated veins (49%). Posterior wall ablation was added in 125 patients (67%). Major complications occurred in 1 patient (transient ischemic attack 0.5%). Freedom from arrhythmia recurrence in Kaplan-Meier-analysis was 78% after 6 months and 54% after 12 months.

Conclusion

PFA is a versatile and safe option for repeat procedures after failed prior thermal ablation.

Contemporary catheter ablation of complex atrial tachycardias after prior atrial fibrillation ablation: pulsed field vs. radiofrequency current energy ablation guided by high-density mapping

AIMS

Catheter ablation (CA) of post-ablation left atrial tachycardias (LATs) can be challenging. So far, pulsed field ablation (PFA) has not been compared to standard point-by-point radiofrequency current (RFC) energy for LAT ablation. To compare efficacy of PFA vs. RFC in patients undergoing CA for LAT.

METHODS AND RESULTS

Consecutive patients undergoing LAT-CA were prospectively enrolled (09/2021-02/2023). After electro-anatomical high-density mapping, ablation with either a pentaspline PFA catheter or RFC was performed. Patients were matched 1:1. Ablation was performed at the assumed critical isthmus site with additional ablation, if necessary. Right atrial tachycardia (RAT) was ablated with RFC. Acute and chronic success were assessed. Fifty-six patients (n = 28 each group, age 70 ± 9 years, 75% male) were enrolled.A total of 77 AT (n = 67 LAT, n = 10 RAT; 77% macroreentries) occurred with n = 32 LAT in the PFA group and n = 35 LAT in the RFC group. Of all LAT, 94% (PFA group) vs. 91% (RFC group) successfully terminated to sinus rhythm or another AT during ablation (P = 1.0). Procedure times were shorter (PFA: 121 ± 41 vs. RFC: 190 ± 44 min, P < 0.0001) and fluoroscopy times longer in the PFA group (PFA: 15 ± 9 vs. RFC: 11 ± 6 min, P = 0.04). There were no major complications. After one-year follow-up, estimated arrhythmia free survival was 63% (PFA group) and 87% (RFC group), [hazard ratio 2.91 (95% CI: 1.11-7.65), P = 0.0473].

CONCLUSION

Pulsed field ablation of post-ablation LAT using a pentaspline catheter is feasible, safe, and faster but less effective compared to standard RFC ablation after one year of follow-up. Future catheter designs and optimization of the electrical field may further improve practicability and efficacy of PFA for LAT.