Pulsed electric field, cryoballoon, and radiofrequency for paroxysmal atrial fibrillation ablation: a propensity score-matched comparison

Pulsed-field ablation versus cryoballoon ablation in patients with persistent atrial fibrillation

Background

Current thermal energy sources such as cryoballoon (Cryo) ablation technology are associated with high rates of reconnected pulmonary veins (PV), especially in patients with persistent atrial fibrillation (AF). Pulsed-field ablation (PFA) may represent a more suitable ablation modality for this patient population. This study aims to compare the efficacy, and safety of PFA and Cryo in patients undergoing a PVI only approach for persistent AF.

Method

Patients with persistent AF who underwent PVI at a tertiary referral center using either PFA or Cryo were consecutively enrolled.

Results

A total of 220 patients (median age 66 [60-72] years, 24 % female) were included out of which 113 patients (51 %) underwent PFA and 107 patients (49 %) Cryoablation. Median procedure duration, LA dwell time and fluoroscopy time were shorter in the PFA group: 49 [39-61] min vs 60 [49-75] min (p < 0.001), 34 [25-43] min vs 37 [31--53] min (p < 0.001), and 9 [[8], [9], [10], [11], [12], [13]] min vs 11 [[8], [9], [10], [11], [12], [13], [14], [15], [16]] min (p = 0.008). During a median follow-up of 365 days, recurrence-free survival was 72 % in the PFA group and 60 % in the Cryo group (pLog-rank = 0.079). The change in AF type from persistent AF to paroxysmal AF was more frequently observed after PFA than after Cryo (68 % vs 37 %; p = 0.011).

Conclusion

In patients with persistent AF undergoing a PVI only approach, PFA was associated with shorter procedural times and similar efficacy, with a higher frequency of regression from persistent to paroxysmal AF. Future studies are needed to evaluate the role of ablation strategies beyond PVI when using PFA.

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.

Catheters and Tools with Pulsed Field Ablation-Pulmonary Vein Isolation with Focal Lattice-Tip Affera Sphere 9

The Affera system features a versatile and large footprint catheter with a lattice-tip design that is capable of delivering both pulsed field and radiofrequency energy. It provides precise mapping and ablation capabilities, demonstrating high acute success rates and durable lesion formation, with excellent safety profile in both radiofrequency and pulsed field ablation modes. Preclinical and clinical studies have shown high lesion durability, reduced procedural time, and promising outcomes in pulmonary vein isolation with minimal complications.

Current Safety Profile of Pulse Field Ablation: Not Everything that Shines Is Gold

Pulse field ablation is a novel, non-thermal alternative for catheter ablation of atrial fibrillation. Preclinical and early clinical studies have demonstrated a favorable safety profile with significant reductions in esophageal and pulmonary vein injury compared to radiofrequency ablation. However, there are still procedural and energy-related complications inherent to electroporation, tissue selectivity, and energy-dosing. Minimizing the frequency of application and extent of energy, as well as careful selection of the energy source, may mitigate these adverse events. There remains controversy and a lack of long-term outcomes, highlighting the need for further evaluation.

Efficacy and Safety of Pulsed-Field Versus High-Power Short-Duration Ablation for Atrial Fibrillation: A Systematic Review and Meta-Analysis With Reconstructed Time-to-Event Data

BACKGROUND

Pulsed-field ablation (PFA) and high-power short-duration (HPSD) ablation (45-90 W) are emerging technologies in atrial fibrillation (AF) treatment, both achieving durable pulmonary vein isolation. We aim to investigate the efficacy and safety of PFA versus HPSD ablation.

METHODS

We comprehensively searched PubMed, Web of Science (WOS), Scopus, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) through July 2024. Pairwise meta-analysis with reconstructed time-to-event analysis were performed using R version 4.3.1 (PROSPERO ID: CRD42024576031).

RESULTS

Seven observational studies, including 1904 patients, were included. PFA was significantly associated with lower atrial tachyarrhythmia recurrence compared to HPSD ablation (45-90 W) at the longest follow-up (RR: 0.73, 95% CI [0.60, 0.88], p < 0.01). Subgroup analysis revealed a significant reduction in atrial tachyarrhythmia recurrence with PFA versus HPSD ablation (45-50 W) (RR: 0.69, 95% CI [0.54, 0.88], p < 0.01), but not compared to vHPSD ablation (70-90 W). Reconnected pulmonary vein rates were significantly lower with PFA compared to HPSD (45-50 W) (p = 0.03), while no significant difference was observed compared to vHPSD (70-90 W). PFA was significantly associated with reduced procedural duration (MD: -33.15 with 95% CI [-40.93, -25.36], p < 0.01) and left atrial dwell time (MD: -32.16 with 95% CI [-45.55, -18.77], p < 0.01), although fluoroscopy time increased (MD: 7.48 with 95% CI [4.29, 10.68], p < 0.01) compared to HPSD ablation (45-90 W). Safety profiles were comparable, but pericarditis rates were significantly lower with PFA versus HPSD (45-50 W) (p = 0.003) and vHPSD (70-90 W) (p = 0.019). Kaplan-Meier analysis showed a 28% lower risk of atrial tachyarrhythmia recurrence with PFA compared to HPSD ablation (45-90 W) (HR: 0.72, 95% CI [0.57, 0.91], p = 0.006) over an 18-month follow-up.

CONCLUSION

PFA and HPSD ablation (45-90 W) are effective and safe for AF ablation. PFA was significantly associated with lower atrial tachyarrhythmia recurrence, shorter procedural duration, reduced left atrial dwell time, increased fluoroscopy time, and comparable safety, with lower rates of pericarditis compared to HPSD ablation.

Ensuring catheter-tissue contact with intra-cardiac echocardiography during pulsed-field ablation improves procedure outcome in patients with atrial fibrillation

BACKGROUND

Catheter-tissue contact is critical in creating durable lesions during pulsed-field ablation (PFA) of atrial fibrillation (AF).

OBJECTIVE

We aimed to compare the reconnection rate of previously ablated targets utilizing PFA with vs without intracardiac echocardiography (ICE)-guidance for confirmation of tissue contact.

METHODS

This multicenter prospective study included consecutive paroxysmal and persistent AF patients undergoing their first procedure using the PFA system. Patients were classified as ICE-group if ICE was used for assessment of catheter-tissue-contact (n=310) or Fluoro-group: fluoroscopy-guided ablation (n=286). All patients received isolation of PVs (PVI); left atrial posterior wall (LAPW) was done in most at the index procedure. Further ablations were performed only in the presence of spontaneous triggers or documentation that those triggers were responsible for arrhythmia either spontaneously or after isoproterenol challenge.

RESULTS

Baseline characteristics were comparable between the groups. At the end of the follow-up, arrhythmia recurrence was noted in 39 (12.6%) and 64 (22.3%) patients in the ICE and fluoro-group respectively (p=0.002). All 39 patients in the ICE-group and 54 (84%) patients in the fluoro-group received repeat ablation. At the redo procedure, reconnection of previously ablated structures was detected in 4/39 (10.3%) and 32/54 (59.2%) patients in the ICE and fluoro-group respectively (p<0.001). 'Fluoroscopy-guided' ablation was found to be an independent predictor of reconnection (OR = 8.548 95% CI 3.224 - 22.667; p- value = <0.001) as well as recurrence (OR: 1.221, 95% CI 1.001 - 1.971, p=0.021).

CONCLUSION

ICE-guided PFA with confirmed catheter-tissue contact was associated with better success rate and significantly lower reconnection rate in AF patients.

Digital twins enable stratification of persistent atrial fibrillation patients for ablation diminishing unnecessary heart damage

Pulmonary vein isolation (PVI), the standard-of-care for atrial fibrillation (AF), is effective even in some persistent AF (PsAF) patients despite atrial fibrosis proliferation, suggesting that PVI could not only be isolating triggers but diminishing arrhythmogenic substrates. Left atrial (LA) posterior wall isolation is the prevalent adjunctive strategy aiming to address PsAF arrhythmogenesis, however, its outcomes vary widely. To explore why current PsAF ablation treatments have limited success and under what circumstances each treatment is most effective, we utilized patient-specific heart digital twins of PsAF patients incorporating fibrosis distributions to virtually implement versions of PVI (individual ostial to wide antral) and posterior wall isolation. In most digital-twins (60%) PVI greatly decreased LA substrate arrhythmogenicity without the need of wider lesions or posterior wall isolation. Using digital-twin findings, a strategy was developed to stratify PsAF patients to an appropriate ablation option based on fibrosis features, thus potentially avoiding unnecessary heart damage.

Does Age Impact Safety and Efficacy During Pulse-Field Ablation for Atrial Fibrillation?

BACKGROUND

There is no evidence evaluating efficiency, effectiveness, and safety outcomes in older patients in the context of pulsed-field ablation technology for the ablation of atrial fibrillation. We aimed to compare safety, efficacy, and acute and long-term outcomes of pulsed-field ablation in older patients (≥75 years) with younger ones.

METHODS

We enrolled consecutive patients who had undergone atrial fibrillation ablation with the pulsed-field ablation FARAPULSE system (Boston Scientific) at 15 centers. Patients were stratified by age (<65, 65-74, and ≥75 years) and efficacy and safety profiles of these groups were compared.

RESULTS

A total of 1082 patients were included: 108 (10%) were ≥75 years old, 374 (34.6%) were 65-74 years old and 600 (55.4%) were <65 years old. Older patients displayed a more pronounced risk profile compared with their younger counterparts, characterized by a significant higher burden of comorbidities. No differences in terms of procedural metrics were found. Pulmonary vein isolation was achieved in all patients. An overall low rate of procedural-related complications was reported (3.0%) without difference between young and older patients (P=0.241). During a mean follow-up of 342±111 days, a primary efficacy end point occurred in 605 of 748 (80.9%) patients with available outcome information. The arrhythmia recurrence rate ranged from 14.4% in patients <65 years old to 26.9% of older patients (P=0.011).

CONCLUSIONS

Drawing from these findings, using the FARAPULSE system for atrial fibrillation ablation in older patients demonstrated swift, safe, and effective acute outcomes, mirroring a comparable pattern observed in younger patients and recurrence rates in line with the literature in older patients.

REGISTRATION

URL: clinicaltrials.gov; Unique Identifier: NCT05617456.

Left atrial substrate modification in addition to pulmonary vein isolation using a novel circular variable loop pulsed field ablation catheter

Background

Pulsed field ablation (PFA) is a recently developed technology that causes tissue necrosis through electroporation and has been employed and validated for pulmonary vein isolation (PVI) in atrial fibrillation (AF) ablation. Only few devices have received a CE mark for this use and the VaripulseTM catheter (VaripulseTM, Biosense Webster, Irvine, USA), a variable loop PFA catheter, has been recently approved. Despite the growing experience with PVI, evidence is lacking about the use of PFA catheters and linear ablation lesions, which could potentially be performed with PFA catheters, reducing procedure related costs and time.

Case summary

A 73-year-old Caucasian woman with multiple cardiovascular risk factors presented with highly symptomatic paroxysmal AF and was scheduled to undergo PFA AF ablation using the new Varipulse catheter. The procedure was performed under deep sedation and the catheters were advanced through trans-septal puncture. 3D electroanatomic mapping of the left atrium showed significant anterior wall fibrosis. After PVI, substrate modification through an anterior mitral line (AML) approach was pursued. The AML was performed with additional PFA applications and successful bidirectional block was confirmed by pacing maneuvers without any procedural complications. The patient was discharged the following day, asymptomatic and in a state of well-being.

Conclusion

Individual LA substrate modification, including linear lesion sets, can be delivered in addition to PVI using the novel Varipulse PFA catheter in patients with AF.

Comparing efficacy and safety between pulsed field ablation, cryoballoon ablation and high-power short duration radiofrequency ablation in atrial fibrillation: a systematic review and network meta-analysis

BACKGROUND

Pulsed field ablation (PFA) and high-power short-duration radiofrequency ablation (HPSD) are emerging techniques for treating atrial fibrillation (AF), offering promising results compared to cryoballoon ablation (CBA). This network meta-analysis aims to evaluates the efficacy and safety of PFA, HPSD, and CBA.

METHOD

PubMed, Scopus and Cochrane Central Register of Controlled Trials were systematically searched for relevant studies until October 2024. The primary outcome is freedom from atrial arrhythmia. A random-effects model was used for data synthesis, and P-scores were employed for outcome ranking. Point estimation (odd ratios) was calculated for comparisons.

RESULTS

Eighteen studies were included in our network meta-analysis, involving 7,071 atrial fibrillation patients. Among them, 2,023 (29%), 3,725 (53%), and 1,323 (18%) patients underwent PFA, CBA, and HPSD, respectively. PFA demonstrated a higher freedom from atrial arrhythmia, with an odds ratio (OR) of 3.63 (95% CI: 2.95-4.46) compared to CBA and 1.89 (95% CI: 1.47-2.43) compared to HPSD. However, PFA was associated with a higher risk of complications (OR = 6.54, 95% CI: 2.13-20.00) compared to CBA, while HPSD showed an insignificant association with a lower risk of complications compared to CBA (OR = 0.61, 95% CI: 0.15-2.42). PFA had the shortest procedural time (P-score: 100%), while HPSD had the longest (P-score: 0%). In contrast, HPSD had the shortest fluoroscopic time, with P-scores of 100%, 46%, and 3% for HPSD, PFA, and CBA, respectively.

CONCLUSION

PFA demonstrated higher efficacy but also a higher risk of complications compared to HPSD and CBA. HPSD showed greater efficacy with comparable safety to CBA.

A Hybrid Minimally Invasive Atrial Fibrillation Ablation Procedure Using Unilateral Thoracoscopy and Endocardial Pulsed Field Ablation: An Early Feasibility Study

(1) Objective: To examine the efficiency and efficacy of using endovascular mapping and pulsed field ablation in the setting of a hybrid video-assisted thoracoscopic atrial fibrillation (AF) ablation procedure. (2) Methods: Eleven consecutive patients underwent hybrid video-assisted thoracoscopic epicardial ablation and left atrial appendage exclusion followed by endocardial ablation using pulsed field ablation energy. The completeness of epicardial and endocardial lesion sets were assessed using 3D electro-anatomical mapping. (3) Results: Left atrial appendage (LAA) exclusion and durable pulmonary vein isolation (PVI) and posterior wall isolation (PWI) were achieved in all patients. The endovascular part of the necessary lesion set using PFA energy was successful in 100% of the patients. All patients remained in SR during the 12-month follow-up period. (4) Conclusions: Our study confirms the feasibility of using endovascular pulsed field ablation to complete previously performed epicardial lesion sets during the hybrid AF ablation procedures, without extending the procedure time or increasing the risk of complications.

Hemolysis Biomarkers After Pulmonary Vein Isolation via a Balloon-In-Basket PFA Catheter

INTRODUCTION

The extensive use of pulsed field ablation (PFA) in clinical settings has unveiled new evidence suggesting potential involvement in red blood cell structural impairment resulting in hemolysis and potential acute kidney injury (AKI).

METHODS

In this study, blood samples were collected from 16 patients before and 24 h after pulmonary vein isolation (PVI) via a novel investigational PFA-based technology. Biochemical analyses were performed to assess hemolysis and AKI, including total and indirect bilirubin, lactate dehydrogenase (LDH), haptoglobin, plasma free hemoglobin, urea, creatinine, and estimated glomerular filtration rate (eGFR).

RESULTS

Based on the periprocedural changes in hemolysis biomarkers, none of the patients displayed evidence of clinically relevant hemolysis following PVI with the PFA catheter.

Hemolysis after pulsed-field ablation of atrial fibrillation

Pulsed-field ablation (PFA) offers notable advantages in atrial fibrillation (AF) ablation by selectively targeting cardiomyocytes via an irreversible electroporation mechanism, thereby minimizing damage to surrounding tissues. Although clinical studies demonstrate that PFA is both safe and effective, PFA-mediated hemolysis and potential acute kidney injury (AKI) have been recently reported. This study comprehensively reviews the literature on PFA-associated hemolysis, analyzing the underlying mechanisms, risk factors, and preventive management strategies. In addition, the review discusses approaches to minimize the risk of PFA-induced hemolysis and AKI while offering insights for improving PFA-associated techniques.

Impact of the dispersive patch placement on dissipated power in radiofrequency ablation for pulmonary vein isolation via a virtual patient study

Radiofrequency ablation (RFA) is a minimally invasive technique for treating arrhythmias by interrupting abnormal electrical signals in the heart. Through a catheter tip, it delivers an alternating current that flows through the heart muscle tissue and the blood to a dispersive patch on the patient's skin. This study aims to test the hypothesis that the placement of the dispersive patch affects the efficacy and safety of RFA. By optimizing the patch position, the procedure could be made more effective and less risky for patients. A 3D in-silico model, based on patient imaging data, was developed to examine the effects of dispersive patch (DP) positioning on electric field distribution within cardiac tissue and the torso during RFA. We conducted 80 computer simulations using a CT-segmented torso model, exploring various DP and electrode configurations while applying standard (25 W) and high (90 W) power settings. For each configuration, we assessed the effectiveness of the DP in delivering power to cardiac tissue near the electrode. The main finding indicates that DP efficacy is significantly influenced by the current delivered to cardiac tissue. Notably, using an anterior patch during ablation proved more effective for the posterior left atrium compared to a posterior patch.

Pulsed field ablation for atrial fibrillation: a comprehensive bibliometric analysis of research trends and emerging Frontiers

Background

Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia worldwide, posing significant health burdens. Pulsed field ablation (PFA) is an emerging non-thermal technique that is gaining traction due to the ability to selectively target myocardial cells and minimize damage to surrounding tissues. We conducted a comprehensive bibliometric analysis of PFA use in AF treatment to map research trends, collaborations, and future directions.

Methods

We extracted data from the Web of Science Core Collection on September 6, 2024, using search terms related to PFA and AF. Publication trends, citation trajectories, collaborative networks, and keyword co-occurrences were analyzed utilizing tools such as Bibliometrix R, VOSviewer, and CiteSpace.

Results

In total, 217 publications were retrieved. The number of publications increased rapidly from 2019 to 2024, with a notable surge occurring after 2022. Contributions from the United States, Germany, and China accounted for more than 60% of all publications. The institution with the largest output was The Icahn School of Medicine at Mount Sinai. The most productive journals were Europace and the Journal of Interventional Cardiac Electrophysiology. Prolific authors were identified, underscoring significant international collaborations. The most cited publications highlighted the efficacy and safety of PFA. Keywords with strong recent citation bursts included "tissue", "cardiomyopathy", and "closed chest ablation".

Conclusion

PFA is becoming established as a viable alternative for AF ablation, showing promising safety and efficacy. This bibliometric analysis confirmed the growing scientific interest and collaborative efforts in this field, suggesting that robust future developments will occur.

Early versus late atrial fibrillation recurrence after pulsed field ablation: insights from the admIRE trial

AIMS

Studies have shown correlations between early recurrence (ER) and late recurrence (LR) of atrial arrhythmia after ablation with thermal technologies. This admIRE trial (NCT05293639) subanalysis aims to analyse ER vs. LR in patients with paroxysmal atrial fibrillation (PAF) undergoing pulsed field ablation (PFA).

METHODS AND RESULTS

Patients with symptomatic paroxysmal atrial fibrillation and ≥1 transtelephonic monitoring transmission during the blanking period were included (n = 169). ER was defined as documented recurrence in the blanking period (days 1-90), and LR as recurrence in the evaluation period (days 91-365). Freedom from 12-month recurrence was estimated using Kaplan-Meier method. A Cox proportional-hazards regression model, with ER as the primary factor, and adjusted for age, sex, and body mass index, was used to estimate hazard ratios (HRs) and 95% CI. ER was observed in 20.1% (31/169) of patients (66.1 ± 7.1 years, 35.5% female, 46.6 ± 48.4-month PAF history). Time to first documented ER was 49 (37-61) days. Occurrence of LR was 16.7% (23/138) in patients without ER, 71.0% (22/31) in those with ER, and 87.0% (20/23) in patients whose ER onset occurred within the first 2 months. Twelve-month freedom from documented recurrence was significantly lower in patients with ER at 29.0% (95% CI, 13.1-45.0%) vs. 82.5% (95% CI, 75.9-89.1%) in those without ER (adjusted HR, 7.9; 95% CI, 4.1-15.1; P < 0.001).

CONCLUSION

This admIRE subanalysis demonstrated that PAF patients who experience ER after PFA are at a substantially higher risk for LR. The optimal duration of the blanking period post-PFA needs further assessments.

CLINICALTRIALS.GOV IDENTIFIER

NCT05293639.

Feasibility and safety of zero-fluoro, "apron-less" approach to repeat pulmonary vein isolation procedures using radiofrequency energy after initial cryoballoon ablation

We aimed to investigate the feasibility and safety of zero-fluoro approach for the repeat atrial fibrillation (AF) procedures after initial cryoballoon (CB) ablation. We have performed a retrospective study on patients that have undergone repeat pulmonary vein isolation (PVI) procedures in our institution since zero-fluoro program was initiated in 2020. All patients received CB ablation for the initial procedure. Repeat procedures were performed under conscious sedation and with intracardiac echo (ICE) and 3D mapping system - without the use of fluoroscopy and lead aprons. We have analysed in total 50 patients (76% male, 57.9 ± 10.2 years old), 50% of which suffered from paroxysmal AF. All procedures were successfully performed without the use of fluoroscopy. The mean procedure time was 93.9 ± 27.1 min and the mean RF time was 825 ± 468 s. The mean of 0.98 ± 0.91 veins was reconnected per patient and 36% of patients did not have PV reconnections. In all patients successful PV isolation was performed, confirmed by entry and exit block. No major periprocedural complications were observed. After the mean follow up of 12.5 ± 3.4 months: 68% of mixed AF population patients were free from AF after one year. In our cohort of patients, zero-fluoro, apron-less approach for repeat PVI procedures after index cryoballoon ablation proved to be feasible and safe. Index CB ablation resulted with low rates of PV reconnections and mid-term results after repeat procedures are favourable.

Meta-Analysis of Pulsed-Field Ablation Versus- High-Power Short-Duration Ablation for Atrial Fibrillation

PURPOSE

To optimize the effectiveness and safety of pulmonary vein isolation, pulsed-field ablation (PFA) and high-power short-duration ablation (HPSD) have recently been incorporated into clinical practice. The objective of this study is to conduct a comparative analysis, focusing on the efficacy, safety, and procedural efficiency of PFA and HPSD in the treatment of atrial fibrillation (AF).

METHODS

A thorough search was performed across multiple databases to identify trials that compared PFA with HPSD for AF from their inception until July 2024. The odds ratio (OR) and mean difference (MD), accompanied by a 95% confidence interval (CI), were employed as indicators of treatment efficacy.

RESULTS

The analysis included six eligible trials, encompassing a total enrollment of 1382 patients. No statistically significant disparities were observed in terms of freedom from any atrial arrhythmia (OR 1.10; 95% CI 0.75, 1.63) or periprocedural complications (OR 1.04; 95% CI 0.52, 2.09) between the two ablation techniques. The likelihood of requiring a repeat ablation procedure was significantly reduced with PFA compared to HPSD (OR 0.63; 95% CI 0.41-0.97); however, there was no significant difference in the incidence of PV reconnection between patients initially treated with HPSD and those using PFA (OR 0.83; 95% CI 0.53-1.30). The PFA technique demonstrated significantly shorter procedure time (MD -34.58; 95% CI -45.20, -23.96) and left atrium (LA) dwell time (MD -34.52; 95% CI -58.42, -10.61), but longer fluoroscopy time (MD 8.81; 95% CI 6.25, 11.37). The subgroup analyses revealed that PFA continued to exhibit superior procedure time and LA dwell time but inferior fluoroscopy time.

CONCLUSION

The efficacy and safety profiles of both PFA and HPSD are comparable in patients undergoing ablation therapy for AF; however, PFA is associated with shorter procedural time and longer fluoroscopy time.

Clinical, Electrocardiographic and Echocardiographic Predictors of Atrial Fibrillation Recurrence After Pulmonary Vein Isolation

Atrial fibrillation (AF) is a supraventricular arrhythmia and the most common heart rhythm disorder in the adult population worldwide with an estimated prevalence of 2% to 4% of the population. Cases of AF have shown an increasing trend in recent decades, while its frequency is expected to rise even more. Given the significant impact on patients' quality of life, as well as its major complications, including thromboembolic events, effective rhythm control strategies other than antiarrhythmic medication have emerged, with catheter ablation (CA) being the cornerstone of these. In recent years, CA has been upgraded to a first-line treatment for selected patients. However, complications do exist and arrhythmia-free survival is not always guaranteed. The need to better identify patients more suitable for this specific therapeutic measure is crucial in improving outcomes and preventing arrhythmia recurrences. This review aims to present currently identified predictors of AF recurrence after catheter ablation based on clinical characteristics and electrocardiographic and echocardiographic parameters, in an era of increasing interventional rhythm control approaches for the management of atrial fibrillation.

Pulsed field ablation in the elderly by a pentaspline multielectrode catheter: Safety, efficacy, and comparison with cryoballoon and radiofrequency devices

BACKGROUND

Catheter ablation is an effective treatment of atrial fibrillation. Pulsed field ablation (PFA) has emerged as a novel energy modality that relies on high-voltage electric fields to achieve cardiac tissue ablation. Data on its efficacy in the elderly are scarce.

OBJECTIVE

This study aimed to evaluate the procedural details and clinical outcomes of PFA in patients >75 years old.

METHODS

Consecutive patients with atrial fibrillation >75 years old undergoing PFA with the Farapulse system were enrolled at 6 high-volume centers. Procedural details and clinical outcomes were compared with those of patients undergoing second-generation cryoballoon ablation (CBA) and radiofrequency ablation (RFA).

RESULTS

Of 983 patients, 221 underwent PFA, 216 CBA, and 546 RFA. Procedure times were shorter with PFA (72 ± 30 minutes) compared with CBA (77 ± 27 minutes) and RFA (99 ± 23 minutes; P < .001). Extra-pulmonary vein ablation was performed in 74.2% PFA, 9.7% CBA, and 42.1% RFA (P < .001). The major complication rate was 1.01% (n = 10) and was not significantly different between groups (1 PFA, 2 CBA, and 7 RFA; P = .578). Minor complications were observed in 1.4% PFA, 5.1% CBA, and 3.5% RFA (P = .093). The 1-year atrial tachyarrhythmia freedom in the propensity score-matched population was 77.2% with PFA, 80.8% with CBA, and 74.9% with RFA; P = .52).

CONCLUSION

PFA is a safe and effective option for elderly patients, offering the advantage of enabling extra-pulmonary vein ablation without the concern of thermal injury risk.

Effectiveness and Safety of Pulsed Field Ablation in Patients With Atrial Fibrillation

BACKGROUND

As a competitive nonthermal energy technique used in atrial fibrillation (AF), the effectiveness and safety of pulsed field ablation (PFA) has remained uncertain.

OBJECTIVES

The authors meta-analysis aimed to investigate the effectiveness and safety of PFA in treating AF patients and compare its outcomes with conventional thermal ablation.

METHODS

The PubMed, Embase, and Cochrane Library databases were systematically searched until January 2024 for relevant studies investigating the use of PFA for AF. A fixed-effects model was used for pooled analysis if the I2 value was <50%; otherwise, a random-effects model was applied.

RESULTS

A total of 46 studies were included in this analysis. The single-arm meta-analysis of 40 studies showed an acute pulmonary vein isolation (PVI) rate of 99.79% per pulmonary vein (PV) and 99.47% per patient, with atrial arrhythmia recurrence rates of 12.36%, 12.42%, and 23.28% at 3, 6, and 12 months, respectively. The safety outcomes incidence was low. In the comparison of 21 studies between PFA and thermal ablation, PFA demonstrated comparable acute PVI rates but a higher first-pass isolation rate. PFA was associated with a lower incidence of atrial arrhythmia recurrence after 3 months and phrenic nerve paralysis or injury, but a higher risk of cardiac perforation or tamponade. Procedure time was shorter with PFA.

CONCLUSIONS

PFA showed noninferiority to thermal ablation in acute PVI and superiority in first-pass isolation, atrial arrhythmia recurrence, phrenic nerve paralysis or injury, and procedure time. However, PFA treatment exhibited a higher risk of cardiac perforation or tamponade.

Safety and Feasibility of Pulsed-Field Ablation in Patients With Mechanical Prosthetic Valves

BACKGROUND

Pulsed-field ablation (PFA) is a novel ablation energy source, which leads to selective and irreversible electroporation of cardiomyocytes with no collateral damage to adjacent tissues. The presence of mechanical prosthetic valves may pose some issues related to catheter manipulation and risk of electromagnetic interference.

OBJECTIVES

The purpose of this study was to assess the feasibility of PFA in patients with mechanical prosthetic valves.

METHODS

The authors enrolled 30 consecutive patients (age 64.7 ± 11.4 years; 43% men) with mitral and/or aortic valve replacement with mechanical substitutes undergoing endocardial AF ablation via a PFA technology at 6 institutions.

RESULTS

Time between valve surgery and ablation was 6.6 ± 6.5 years; 14 (46.7%) patients had an aortic mechanical valve, 10 (33.3%) a mitral, and 6 (20.0%) both. The following PFA technologies were used: FARAWAVE in 25 patients, Sphere-9 in 2, PulseSelect in 2, and the CENTAURI System in 1. No periprocedural and 1-month postablation major and minor complications were observed. Postprocedural transthoracic echocardiography did not identify any prosthetic valve dysfunction. One patient showed electromagnetic interference of the PFA catheter adjacent to the mitral prosthesis without clinical implications. No energy delivery to the mitral edge of the isthmus was possible despite multiple attempts to reposition the catheter. Mean procedural time was 77.5 ± 29.9 minutes, whereas mean left atrial dwell and fluoroscopy times were 43.1 ± 21.4 and 14.0 ± 6.4 minutes, respectively.

CONCLUSIONS

PFA in patients with mechanical valves appears safe, but careful catheter handling is essential to avoid electromagnetic interference hindering PFA delivery.

Efficacy, safety, and somatosensory comparison of pulsed-field ablation and thermal ablation: outcomes from a 2-year follow-up

BACKGROUND

Pulsed-field ablation (PFA), as a nonthermal ablative approach for atrial fibrillation, has attracted much attention in recent years. And there are few comparative studies on PFA versus conventional thermal ablation, including radiofrequency ablation (RFA) and cryoballoon ablation (CBA). The efficacy, safety, and somatic sensation of PFA and thermal ablation need to be further compared.

METHODS

A total of 109 patients with paroxysmal atrial fibrillation were divided into three groups (27 in the PFA group, 41 in the CBA group, and 41 in the RFA group), and the operation characteristics, efficacy, safety, and somatic sensation were recorded and analyzed. All patients were followed for 2 years.

RESULTS

All pulmonary veins were successfully isolated except for 1 pulmonary vein that was not successfully isolated during the CBA process (PFA vs. CBA vs. RFA = 100% vs. 99% vs. 100%). The total operation time for PFA is considerably shorter than that for thermal ablation (PFA vs. CBA vs. RFA = 65.28 ± 22.78 min vs. 75.38 ± 18.53 min vs. 96.26 ± 23.23 min, P < 0.001), and the same applies to all the sub-phases. PFA was similarly more dominant in terms of somatosensory perception, mainly in headache (PFA vs. CBA = 1.17 ± 0.48 vs. 2.31 ± 1.06, P < 0.001) and chest pain (PFA vs. RFA = 1.45 ± 0.88 vs. 2.52 ± 1.06, P < 0.001). All these three groups demonstrated good maintenance rates (PFA vs. CBA vs. RFA = 85.00% vs. 80.49% vs. 78.05%, 2 years after operation).

CONCLUSION

PFA demonstrates its excellent somatic sensation and favorable safety. And it also showed a great immediate success and maintenance rate, which is not inferior to thermal ablation.

Using computed tomography atrial myocardial thickness maps in cryoballoon pulmonary vein isolation: the UTMOST AF II randomized clinical trial

AIMS

Whether adjusting the duration of ablation based on left atrial wall thickness (LAWT) provides extra benefits for pulmonary vein (PV) isolation for atrial fibrillation (AF) is uncertain. We studied the safety and efficacy of tailored cryoballoon PV isolation (CB-PVI) based on LAWT for paroxysmal AF.

METHODS AND RESULTS

Two hundred seventy-seven patients with paroxysmal AF refractory to anti-arrhythmic drug were randomized 1:1 to either LAWT-guided CB-PVI (n = 135) and empirical CB-PVI (n = 142). Empirical CB-PVI was performed using a 28 mm cryoballoon with recommended application for 240 s per ablation. Cryoapplication in the LAWT-guided group was titrated (additional application for 120 s at PVs, where >25% of the circumference includes segments with LAWT > 2.5 mm and reduced baseline application to 180 s at PVs where >75% of the circumference includes segments with LAWT < 1.5 mm) according to the computed tomography LAWT colour map. The primary endpoint was freedom from any documented atrial arrhythmia of more than 30 s without antiarrhythmic medication, after a single ablation procedure. During a mean follow-up of 18.7 months, patients in the LAWT-guided CB-PVI group (70.8%) had a higher event-free rate from primary endpoint than those in the empirical CB-PVI group (54.4%; hazard ratio 0.64, 95% confidence interval 0.42-0.99; P = 0.043). No differences were observed between the groups in complication rates (3.0% in LAWT-guided vs. 4.9% in empirical CB-PVI). The total procedure time was extended in the LAWT group than in the empirical group (mean 70.2 vs. 65.2 min, respectively).

CONCLUSION

The LAWT-guided energy titration strategy improved freedom from atrial arrhythmia recurrence, compared with conventional strategy.

Multielectrode catheter-based pulsed electric field vs. cryoballoon for atrial fibrillation ablation: a systematic review and meta-analysis

AIMS

Pulsed field ablation (PFA) is an innovative technology recently adopted for the treatment of atrial fibrillation (AF). Preclinical and clinical studies have reported a remarkable safety profile, as a result of its tissue-specific effect targeting cardiomyocytes and sparing adjacent tissues. Single-shot pentaspline system was the first PFA device to receive regulatory approval. We performed a meta-analysis to compare the efficacy and safety of PFA with the single-shot pentaspline system vs. currently available second-/third-/fourth-generation cryoballoon ablation (CRYO) technologies.

METHODS AND RESULTS

We systematically searched electronic databases for studies focusing on AF ablation employing the PFA single-shot pentaspline system or second-/third-/fourth-generation CRYO technologies. The primary endpoints were acute procedural success assessed on a vein and patient basis. Safety endpoints included overall periprocedural complications and major periprocedural complications. We also compared procedural, fluoroscopy times, and freedom from atrial tachyarrhythmias (ATs) at follow-up (secondary endpoints). Twenty and 70 studies were included for PFA and CRYO, respectively. Pulsed field ablation demonstrated greater acute procedural success on a vein basis (99.9% vs. 99.1%; P < 0.001), as well as per patient (99.5% vs. 98.4%; P < 0.001). Pulsed field ablation yielded lower overall periprocedural complications (3.1% vs. 5.6%; P < 0.001), shorter procedural time (75.9 min vs. 105.6 min; P < 0.001), and fluoroscopy time (14.2 min vs. 18.9 min; P < 0.001) compared with CRYO. No differences were found for major periprocedural complications (1.2% vs. 1.0%; P = 0.46) and freedom from ATs at 1 year (82.3% vs. 80.3%; log-rank P = 0.61).

CONCLUSION

Pulsed field ablation contributed to higher acute procedural success and safety compared with CRYO. No statistically significant differences in AT recurrence at 1-year follow-up were observed.

[Pulsed-field ablation-is it the only energy source for ablation in the future? : Pro/Contra]

Pulsed field ablation (PFA) is a nonthermal energy source used for cardiac ablation procedures. Cell death during PFA occurs via electroporation: ultrarapid (micro- to nanosecond) electrical pulses are applied to destabilize cell membranes causing irreversible pores. PFA leads to preferential ablation of myocardiocytes, sparing adjacent tissue like the esophagus or phrenic nerve. Preliminary clinical studies show high efficacy and a good safety profile in atrial fibrillation patients undergoing pulmonary vein isolation. The question remains, however, whether this new technology will replace well-known and established thermal energy sources like radiofrequency current or cryoablation within the next 5 years.

[Initial ablation of atrial fibrillation-Is pulmonary vein isolation sufficient? : Pro and contra]

Pulmonary vein isolation (PVI) is currently the gold standard for the ablation of atrial fibrillation (AF). Although this procedure shows good success rates, the recurrence rates after PVI alone are significantly higher in advanced AF and in the presence of comorbidities. Therefore, it is important to consider additional arrhythmogenic mechanisms outside the pulmonary veins, depending on the individual case, in order to improve the patients' outcome.

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.

Successful treatment of atrial flutter post-radiofrequency ablation for atrial fibrillation following atrial septal defect occlusion: a case report of pulsed field ablation

Background

Atrial flutter (AFL) is a common arrhythmia following radiofrequency ablation (RFA) for atrial fibrillation (AF), with varying incidence depending on the ablation strategy. Patients with prior atrial septal defect (ASD) occlusion pose challenges for ablation, particularly when the lesions are located near the occluder. Pulsed field ablation (PFA) has emerged as a promising alternative to RFA for the treatment of AF or AFL; however, its use in patients with ASD occlusion remains unexplored.

Case summary

We present the case of a 46-year-old female with a history of ASD occlusion and subsequent RFA for AF. Despite the initial success, she developed symptomatic AFL 3 months post-procedure. Intracardiac echocardiography (ICE)-guided transseptal puncture guided by ICE revealed an AFL originating from the slow conduction area around the ASD occluder. Pulsed field ablation was successfully performed, and AFL was terminated without complications. Post-procedural follow-up demonstrated maintenance of sinus rhythm.

Discussion

Patients with ASD occlusion present unique challenges for ablation, including difficulties in transseptal puncture and risk of injury to the occluder. Pulsed field ablation offers a potential solution, with studies showing fewer reconnected pulmonary veins and larger lesion creation compared with traditional methods. In our case, PFA effectively terminated the refractory AFL, highlighting its utility in this patient population. Moreover, the use of the Jinjiang PFA catheter with pulse circuit self-checking technology ensured procedural safety, particularly near the occluder.

Maintenance of sinus rhythm after electrical cardioversion to identify patients with persistent atrial fibrillation who respond favorably to pulmonary vein isolation: the pre-pacific study

Background

Pulmonary vein isolation (PVI) is successful in approximately 50% of patients with persistent atrial fibrillation (PsAF) at one year. Identifying pre-procedurally the patients who respond favorably to a PVI alone strategy could improve their management. The present study aims to assess the predictive value of clinical response to pre-ablation electrical cardioversion (ECV) to identify the responders to PVI.

Methods

Consecutive patients undergoing catheter ablation for PsAF were retrospectively classified, as "ECV successful" vs. "ECV failure", according to the rhythm of presentation after an ECV performed ≥4 weeks. Clinical and procedural data were analyzed in both groups according to the ablation strategy applied (PVI vs. PVI + substrate modification).

Results

In total, 58 patients (39.4%) had successful ECVs and 89 (60.6%) had failed ECV. Preprocedural characteristics were similar in both groups. Compared to the ECV failure group, patients with successful ECV presented less frequently (34% vs. 60%; P = 0.004) and less extended (21.3 ± 22.2% vs. 38.9 ± 27.4% of LA surface, P = 0.008) low-voltage areas. Over 55 ± 19 weeks of follow-up, AF-free survival was similar in both groups (72.7% vs. 67.8%, p = 0.39). PVI alone resulted in 83% AF-free survival among patients in the ECV successful group at 13 months.

Conclusion

In approximately 40% of patients with PsAF, sinus rhythm can be restored by ECV and maintained for at least 1 month prior to catheter ablation. This clinical response is associated with less abnormal substrate as identified by left atrial voltage mapping and a procedural success rate of >80% with PVI alone.

Multielectrode catheter-based pulsed field ablation of persistent and long-standing persistent atrial fibrillation

AIMS

Rhythm control of non-paroxysmal atrial fibrillation (AF) is significantly more challenging, as a result of arrhythmia perpetuation promoting atrial substrate changes and AF maintenance. We describe a tailored ablation strategy targeting multiple left atrial (LA) sites via a pentaspline pulsed field ablation (PFA) catheter in persistent AF sustained beyond 6 months (PerAF > 6 m) and long-standing persistent AF (LSPAF).

METHODS AND RESULTS

The ablation protocol included the following stages: pulmonary vein antral and posterior wall isolation plus anterior roof line ablation (Stage 1); electrogram-guided substrate ablation (Stage 2); atrial tachyarrhythmia regionalization and ablation (Stage 3). Seventy-two [age:68 ± 10years, 61.1%males; AF history: 25 (18-45) months] patients with PerAF > 6 m (52.8%) and LSPAF (47.2%) underwent their first PFA via the FarapulseTM system. LA substrate ablation (Stage 1 and 2) led to AF termination in 95.8% of patients. AF organized into a left-sided atrial flutter (AFlu) in 46 (74.2%) patients. The PFA catheter was used to identify LA sites showing diastolic, low-voltage electrograms and entrainment from its splines was performed to confirm the pacing site was inside the AFlu circuit. Left AFlu termination was achieved in all cases via PFA delivery. Total procedural and LA dwell times were 112 ± 25 min and 59 ± 22 min, respectively. Major complications occurred in 2 (2.8%) patients. Single-procedure success rate was 74.6% after 14.9 ± 2.7 months of follow-up; AF-free survival was 89.2%.

CONCLUSION

In our cohort, PFA-based AF substrate ablation led to AF termination in 95.8% of cases. Very favourable clinical outcomes were observed during >1 year of follow-up.

Pulsed field vs very high-power short-duration radiofrequency ablation for atrial fibrillation: Results of a multicenter, real-world experience

BACKGROUND

Pulsed field ablation (PFA) and very high-power short-duration (vHPSD) radiofrequency ablation are the most recently introduced technologies for atrial fibrillation (AF) ablation. The procedural performance, safety, and effectiveness of PFA vs vHPSD are currently unknown.

OBJECTIVE

The study aimed to compare PFA with vHPSD for the treatment of paroxysmal or persistent AF.

METHODS

We conducted an observational, multicenter study enrolling 534 consecutive patients (63 ± 9 years; 36% female) with paroxysmal (n = 368 [69%]) or persistent (n = 166 [31%]) AF undergoing ablation by either PFA (Farapulse; n = 192) or vHPSD (90 W/4 seconds; QDOT Micro; n = 342) between 2020 and 2023. Atrial tachyarrhythmia recurrence after a 1-month blanking period was the primary efficacy end point and was assessed both overall and in propensity score-matched patients. The primary safety end point was a composite of procedure-related complications.

RESULTS

Successful pulmonary vein isolation was achieved in all patients, with shorter procedure duration (PFA,70 minutes; vHPSD, 100 minutes; P < .001) but longer fluoroscopy time (PFA, 15 minutes; vHPSD, 7 minutes; P < .001) in the PFA group. PFA was associated with more frequent use of general anesthesia (P < .001). Primary safety outcome events occurred in 19 patients (3.5%), with similar prevalence in both groups (PFA, 4%; vHPSD, 3%; P = .745). After a median follow-up of 12 (9-12) months, survival free from recurrent atrial tachyarrhythmia was similar between the PFA and vHPSD groups, both overall (12-month estimate: PFA, 75%; vHPSD, 76%; log-rank P = .73) and in propensity score-matched patients (n = 342; 12-month estimate: PFA, 75%; vHPSD, 77%; log-rank P = .980).

CONCLUSION

In a large, multicenter experience, PFA was associated with more common use of general anesthesia, shorter procedural times, and longer fluoroscopy exposure compared with vHPSD ablation, with both techniques displaying superimposable safety and efficacy.

Focal Pulsed Field Ablation for Premature Ventricular Contractions: A Multicenter Experience

BACKGROUND

Pulsed field ablation (PFA) is a novel technology for catheter-based atrial arrhythmia treatment. Evidence of its application for ventricular arrhythmia ablation is still limited. In this study, we describe the feasibility and efficacy of focal PFA for premature ventricular contraction (PVC) ablation.

METHODS

A prospective cohort of 20 patients referred for PVC ablation at 2 centers was enrolled, regardless of the presence of structural heart disease, PVC morphology, or previous ablation attempts. All procedures were performed using the CENTAURI System in combination with contact force sensing catheters and 3-dimensional electroanatomical mapping systems. Energy output and the number of applications were left to the operator's discretion.

RESULTS

Eleven (55%) procedures were conducted under general anesthesia, 6 (30%) under deep sedation, and 3 (15%) under light sedation. Muscular contraction was observed in one case (5%). Median procedural and fluoroscopy times were 95.5 and 6.55 minutes, respectively. The median number of PFA applications was 8 with a median contact force of 10g. A statistically significant (76%) reduction was observed in mean peak-to-peak bipolar electrogram voltage before and after ablation (0.707 versus 0.098 mV; P=0.008). Ventricular irritative firing was observed in 11 (55%) patients after PFA. The median follow-up was 120 days. Acute procedural success was achieved in 17 of 20 (85% [95% CI, 0.70-1]) patients. Two of the patients with procedural failure had late success with >80% clinical PVC burden suppression during follow-up, and 2 of 17 patients with acute success had late PVC recurrence, which accounts for a total of 17 of 20 (85% [95% CI, 0.70-1]) patients with chronic success. Transient ST-segment depression occurred in 1 patient, and the right bundle branch block was induced in 2 others (permanently only in one case).

CONCLUSIONS

PVC ablation using a focal PFA is feasible, effective, and safe, with promising acute and long-term results in several ventricular locations. Irritative firing is frequently observed. Coronary evaluation should be considered when targeting the outflow tract.

Pulsed-field- vs. cryoballoon-based pulmonary vein isolation: lessons from repeat procedures

AIMS

Pulsed-field ablation (PFA) is an emerging technology to perform pulmonary vein isolation (PVI). Initial data demonstrated high safety and efficacy. Data on long-term PVI durability and reconduction patterns in comparison to established energy sources for PVI are scarce. We compare findings in repeat ablation procedures after a first PFA to findings in repeat ablation procedures after a first cryoballoon ablation (CBA) based PVI.

METHODS AND RESULT

A total of 550 consecutively enrolled patients underwent PFA or CBA index PVI. Repeat ablations in patients with symptomatic atrial arrhythmia recurrences were analysed. A total of 22/191 (12%) patients after index PFA-PVI and 44/359 (12%) after CBA-PVI underwent repeat ablation. Reconduction of any pulmonary vein (PV) was detected by multipolar spiral mapping catheter at each PV with careful evaluation of PV potentials and by 3D-mapping in 16/22 patients (73%) after PFA-PVI and in 33/44 (75%) after CBA-PVI (P = 1.000). Of 82 initially isolated PVs after PFA-PVI, 31 (38%) were reconducting; of 169 isolated PVs after CBA-PVI, 63 (37%) were reconducting (P = 0.936). Clinical atrial tachycardia occurred similarly in patients after PFA (5/22; 23%) and CBA (7/44; 16%; P = 0.515). Roof lines were set more often after PFA- (8/22; 36%) compared with CBA-PVI (5/44; 11%; P = 0.023). Repeat procedure duration [PFA: 87 (76, 123) min; CBA: 93 (75, 128) min; P = 0.446] was similar and fluoroscopy time [PFA: 11 (9, 14) min; CBA: 11 (8, 14) min; P = 0.739] equal between groups at repeat ablation.

CONCLUSION

During repeat ablation after previous PFA- or CBA-based PVI, electrical PV-reconduction rates and patterns were similar.

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.

Pulmonary vein isolation using pulsed field ablation vs. high-power short-duration radiofrequency ablation in paroxysmal atrial fibrillation: efficacy, safety, and long-term follow-up (PRIORI study)

AIMS

Pulsed field ablation (PFA) is a novel, non-thermal, cardiac tissue-selective ablation modality. To date, radiofrequency (RF)-guided high-power short-duration (HPSD) ablation represents the gold standard besides cryo-ablation for pulmonary vein isolation (PVI). This single-centre, retrospective study investigated the efficacy of PFA-PVI vs. HPSD-RF PVI in terms of single-procedure arrhythmia-free outcome and safety in a real-world setting.

METHODS AND RESULTS

Consecutive, paroxysmal atrial fibrillation (AF) patients who underwent PVI using PFA or HPSD-RF were enrolled. In group PFA, PVI was performed using a pentaspline PFA catheter. The ablation procedure in group HPSD-RF was performed with RF energy (45 W, ablation index). A total of 410 patients (group PFA, 201; group HPSD-RF, 209) were included. There was no difference between both groups regarding age, gender, and CHA2DS2-VASc score. The procedure time was significantly shorter in group PFA [61 (44-103) vs. 125 (105-143) min; P < 0.001]; fluoroscopy time and dose area product were significantly higher in group PFA [16 (13-20) vs. 4 (2-5) min; P < 0.01 and 412 (270-739) vs. 129 (58-265) μGym2; P < 0.01]. The overall complication rates were 2.9% in group PFA and 6.2% in group HPSD (P = 0.158). There was one fatal stroke in the PFA group. The 1-year Kaplan-Meier estimated freedom from any atrial tachyarrhythmia was 85% with PFA and 79% with HPSD-RF (log-rank P = 0.160). In 56 repeat ablation procedures, the PV reconnection rate was 30% after PFA and 38% after HPSD-RF (P = 0.372).

CONCLUSION

Both PFA and HPSD-RF were highly efficient and effective in achieving PVI in paroxysmal AF patients. The arrhythmia-free survival is comparable. The PV reconnection rate was not different.

Pulsed-field ablation for paroxysmal atrial fibrillation: An indirect comparison of effectiveness among three proprietary devices conducted in the absence of randomized trials

INTRODUCTION

In patients with paroxysmal atrial fibrillation, pulsed-field ablation has been developed as an alternative to thermal ablation. Three devices are currently available: Farawave by Boston, PulseSelect by Medtronic, and Varipulse by Johnson. In the present report, we studied the outcomes at 12 months of these three devices using indirect comparisons.

METHODS

A standard PubMed search was conducted that identified all studies evaluating these devices in patients with paroxysmal atrial fibrillation. The endpoint was freedom from arrhythmia recurrence. Kaplan-Meier curves were subjected to the IPDfromKM method that generated reconstructed patients. Standard time-to-event statistical testss (including heterogeneity assessment) were performed.

RESULTS

Our analysis included 9 studies (8 single-arm and 1 randomized trial based on Farawave for a total of 1916 patients). A significant heterogeneity was found across the trials using Farawave because the outcomes found in the single-arm trials were better than those found in the randomized trial. Farawave (according exclusively to the results of the randomized trial), PulseSelect, and Varipulse showed a similar time-course of their respective outcomes with no significant difference. The single-arm trials using Farawave showed better outcomes than the randomized trial using Farawave and the pivotal trials using PulseSelect and Varipulse.

DISCUSSION

Our study provided an updated overview of all the studies that have so far used pulsed-fileld ablation in patients with paroxysmal atrial fibrillation.

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 versus thermal ablation for atrial fibrillation: A meta-analysis

Background

Pulsed-field ablation (PFA) is an alternative to thermal ablation (TA) in patients with atrial fibrillation (AF) receiving catheter-based therapy for pulmonary vein isolation (PVI). However, its efficacy and safety have yet to be fully elucidated.

Objective

The purpose of this study was to compare the acute and long-term efficacies and safety of PFA and TA.

Methods

We performed a systematic review and meta-analysis of randomized and nonrandomized controlled trials comparing PFA and TA in patients with AF undergoing their first PVI ablation. The TA group was divided into cryoballoon (CB) and radiofrequency subgroups. AF patients were divided into paroxysmal atrial fibrillation (PAF) and persistent atrial fibrillation (PersAF) subgroups for further analysis.

Results

Eighteen studies involving 4998 patients (35.2% PFA) were included. Overall, PFA was associated with a shorter procedure time (mean difference [MD] -21.68; 95% confidence interval [CI] -32.81 to -10.54) but longer fluoroscopy time (MD 4.53; 95% CI 2.18-6.88) than TA. Regarding safety, lower (peri-)esophageal injury rates (odds ratio [OR] 0.17; 95% CI 0.06-0.46) and higher tamponade rates (OR 2.98; 95% CI 1.27-7.00) were observed after PFA. In efficacy assessment, PFA was associated with a better first-pass isolation rate (OR 6.82; 95% CI 1.37-34.01) and a lower treatment failure rate (OR 0.83; 95% CI 0.70-0.98). Subgroup analysis showed no differences in PersAF and PAF. CB was related to higher (peri)esophageal injury, and lower PVI acute success and procedural time.

Conclusion

Compared to TA, PFA showed better results with regard to acute and long-term efficacy but significant differences in safety, with lower (peri)esophageal injury rates but higher tamponade rates in procedural data.

Pulmonary Vein Isolation with Pulsed Field Ablation and Size-Adjustable Cryo-Balloon: A Comparative Procedural Analysis of First-Time Use

Background: Pulmonary vein isolation (PVI) is the standard of care for the treatment of symptomatic atrial fibrillation (AF). Novel techniques for PVI are the thermal size-adjustable cryo-balloon (CB) system and non-thermal pulsed field ablation (PFA) system. There are currently no data available for a direct comparison between these two systems. Furthermore, with new techniques, it is important to ensure a high level of efficiency and safety during treatment right from initial use. Therefore, the aim of this study was to directly compare the procedural data and safety of these two new PVI techniques in first-time users. Methods: We conducted a single-center prospective study involving 100 consecutive patients with symptomatic atrial fibrillation who underwent first-time PVI using either size-adjustable CB PVI or PFA PVI from July 2023 to March 2024. Results: Acute PVI was achieved in 100% of patients in both groups. First-pass isolation (FPI) was more frequently achieved in the PFA group compared to the size-adjustable CB group. The mean procedural duration and fluoroscopy dose were significantly shorter in the PFA cohort (p < 0.001). Furthermore, a significant reduction in fluoroscopy time was observed during the learning curve within the PFA group (p = 0.023). There were no major complications in both groups. Conclusions: Both systems demonstrate good effectiveness and safety during PVI performed by first-time users. However, the PFA group exhibited a significantly shorter procedural duration.

Pulsed Field Energy in Atrial Fibrillation Ablation: From Physical Principles to Clinical Applications

Atrial fibrillation, representing the most prevalent sustained cardiac arrhythmia, significantly impacts stroke risk and cardiovascular mortality. Historically managed with antiarrhythmic drugs with limited efficacy, and more recently, catheter ablation, the interventional approach field is still evolving with technological advances. This review highlights pulsed field ablation (PFA), a revolutionary technique gaining prominence in interventional electrophysiology because of its efficacy and safety. PFA employs non-thermal electric fields to create irreversible electroporation, disrupting cell membranes selectively within myocardial tissue, thus preventing the non-selective damage associated with traditional thermal ablation methods like radiofrequency or cryoablation. Clinical studies have consistently shown PFA's ability to achieve pulmonary vein isolation-a cornerstone of AF treatment-rapidly and with minimal complications. Notably, PFA reduces procedure times and has shown a lower incidence of esophageal and phrenic nerve damage, two common concerns with thermal techniques. Emerging from oncological applications, the principles of electroporation provide a unique tissue-selective ablation method that minimizes collateral damage. This review synthesizes findings from foundational animal studies through to recent clinical trials, such as the MANIFEST-PF and ADVENT trials, demonstrating PFA's effectiveness and safety. Future perspectives point towards expanding indications and refinement of techniques that promise to improve AF management outcomes further. PFA represents a paradigm shift in AF ablation, offering a safer, faster, and equally effective alternative to conventional methods. This synthesis of its development and clinical application outlines its potential to become the new standard in AF treatment protocols.

Radiofrequency catheter ablation for re-do procedure after single-shot pulmonary vein isolation with pulsed field ablation for paroxysmal atrial fibrillation: case report

Background

Catheter ablation is frequently used to manage recurrent atrial fibrillation (AF) resistant to drug therapy, with pulmonary vein isolation (PVI) as a key tactic. Pulsed field ablation (PFA) has emerged as an innovative technology for PVI but poses challenges for redo procedures.

Case presentation

We report on a 73-year-old female patient who experienced recurrent AF after initial successful PVI using a novel PFA technology and subsequently underwent radiofrequency catheter ablation during a repeat intervention. The reconnection of pulmonary veins was discovered primarily in the anterior region of the right superior PV and the superior portion of the left superior PV. An anatomically-based segmental approach and larger circumferential PVI, followed by additional linear ablations at non-PV trigger sites, proved decisive in preventing further recurrence of atrial tachycardia.

Conclusion

While PFA exhibits promise as a secure and efficient modality for PVI, it necessitates excellent contact quality to ensure lasting results. For patients experiencing AF recurrences post-PFI, expanded strategies incorporating both comprehensive PVI and linear ablations at targeted non-PV sites might enhance treatment outcomes.

Efficacy and safety of pulsed field ablation compared to cryoballoon ablation in the treatment of atrial fibrillation: a meta-analysis

Aims

Pulmonary vein isolation (PVI) represents the gold standard in the treatment of atrial fibrillation (AF) and the use of single-shot techniques, such as cryoballoon ablation (CBA) and pulsed field ablation (PFA) using a pentaspline catheter, has gained prominence. Recent studies hypothesize that PFA might be superior to CBA, although procedural efficacy and safety data are inconsistent. A meta-analysis was conducted to compare both energy sources for the treatment of AF.

Methods and results

A structured systematic database search and meta-analysis were performed on studies investigating outcomes, periprocedural complications, and/or procedural parameters of AF patients treated by either CBA or PFA. Eleven studies reporting data from 3805 patients were included. Pulmonary vein isolation by PFA was associated with a significantly lower recurrence of atrial fibrillation/atrial tachycardia [odds ratio (OR) = 0.73, 95% confidence interval (CI) = 0.54-0.98, I2 = 20%] and fewer periprocedural complications (OR = 0.62, 95% CI = 0.40-0.96, I2 = 6%) compared to CBA. The lower complication rate following PFA was mainly driven by fewer phrenic nerve injuries (OR = 0.19, 95% CI = 0.08-0.43, I2 = 0%). However, there were more cases of cardiac tamponades after PFA (OR = 2.56, 95% CI = 1.01-6.49, I2 = 0%). Additionally, using PFA for PVI was associated with shorter total procedure times [mean difference (MD) = -9.68, 95% CI = -14.92 to -4.43 min, I2 = 92%] and lower radiation exposure (MD = -148.07, 95% CI = -276.50 to -19.64 µGy·mI2 = 7%).

Conclusion

Our results suggest that PFA for PVI, compared to CBA, enables shorter procedure times with lower arrhythmia recurrence and a reduced risk of periprocedural complications. Randomized controlled trials need to confirm our findings.

Atrial fibrillation and COVID-19: an analysis of the ambulatory database

Atrial fibrillation (AF) is the most common heart rhythm disorder in clinical practice. It worsens the quality of life of patients, leads to an increase in the mortality rate because of its association with a high risk of thromboembolic complications. The current pandemic of a new coronavirus infection, which began in March 2020, was marked by an increase in cardiovascular diseases, including an increase in the number of patients with AF. That is why it is extremely relevant to find answers to questions about the association and mutual influence of AF and coronavirus infection to reduce the risk of vascular complications. However, most research in this area has focused on hospital patients. In this study, an electronic database of outpatients with AF, including patients with a history of COVID-19 infection was analyzed in order to assess the most significant risk factors for complications.