Procedural efficacy and safety of standardized, ablation index guided fixed 50 W high-power short-duration pulmonary vein isolation and substrate modification using the CLOSE protocol

High-Power Short-Duration Radiofrequency Application for Faster and Safer Pulmonary Vein Isolation: The POWER-FAST III Trial

BACKGROUND

The optimal radiofrequency application (RFa) parameters for safe and durable pulmonary vein isolation (PVI) are debated. High-power short-duration (HPSD) has been used as an alternative to conventional power delivery (CPD).

OBJECTIVES

This study sought to compare HPSD 70 W/9-10 s (HPSD-70) with CPD 25-40 W in patients undergoing PVI.

METHODS

Patients were randomized to HPSD-70 or CPD (25-40). The primary outcomes were freedom from atrial arrhythmia recurrences and the incidence of esophageal thermal lesions (EDELs) after ablation.

RESULTS

Among 304 patients randomized, 301 remained in the study (median age: 61 years; Q1-Q3: 53-69 years; 72% men): 294 patients (97.7%) underwent ablation, 285 (94.7%) underwent endoscopy, and 290 (98.6%) completed the follow-up. At 12 months, 100 patients (73.5%) in the CPD (25-40) group and 87 patients (67%) in the HPSD-70 group were free from recurrences off antiarrhythmic drugs (HR: 1.28; 95% CI: 0.82-1.99; P = 0.28). The incidences of EDELs were 2.7% in the CPD (25-40) group and 3.6% in the HPSD-70 group (P = 0.94). Median left atrial dwell (153 vs 137 min; P = 0.03) and total RF times for definitive PVI (31 vs 11.2 min; P < 0.001) were shorter with HPSD-70 ablation. Four symptomatic embolic events (2 strokes, 1 transient ischemic attack, and 1 splenic infarct) occurred with HPSD-70 and none with CPD (25-40) RFa (P = 0.056).

CONCLUSIONS

HPSD-70 RFa was noninferior to prevent arrhythmia recurrences, and the incidence of EDELs was similar compared with CPD (25-40) RFa. The embolic events were numerically higher in the HPSD-70 group. (High Radiofrequency Power for Faster and Safer Pulmonary Vein Ablation Trial [POWER FAST III]; NCT04153747).

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

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

Safety and efficacy of intracardiac echocardiography-guided zero-fluoroscopy ablation in atrial fibrillation patients: a comparative study of high-power short-duration and low-power long-duration strategies

Introduction

In atrial fibrillation (AF) ablation, fluoroscopy has been a standard tool for catheter guidance. However, the combination of electroanatomic mapping systems (EAMs) and intracardiac echocardiography (ICE) now allows for minimal or zero-fluoroscopy procedures. Concurrently, high-power short-duration (HPSD) ablation has emerged as a promising technique, offering enhanced resistive heating while reducing conductive heating. This approach potentially improves both safety and efficacy. Despite these advancements, there is a lack of comprehensive clinical data on the safety and effectiveness of HPSD ablation when used in conjunction with ICE-guided zero-fluoroscopy procedures.

Objective

To compare two different ablation strategies-high-power short-duration (HPSD) and low-power long-duration (LPLD)-both utilizing intracardiac echocardiography (ICE)-guided zero-fluoroscopy in the context of atrial fibrillation (AF) ablation.

Methods

This retrospective study included 173 consecutive patients with AF who underwent ICE-guided zero-fluoroscopy ablation. Patients were divided into two groups: HPSD and LPLD. All procedures were conducted using an EAM system with ICE guidance. Both groups underwent routine pulmonary vein isolation (PVI), with additional linear ablations performed for persistent AF when necessary. We compared treatment outcomes and the incidence of complications between the two groups.

Results

All procedures were successfully completed under ICE-guided zero-fluoroscopy, establishing a feasible and reliable workflow. The procedure and ablation times were significantly shorter in the HPSD group compared to the LPLD group. At one-year follow-up, sinus rhythm was maintained in 77 patients in the HPSD group and 74 patients in the LPLD group, with no significant difference between the two group. Postoperative complications occurred in 5 patients in the HPSD group and 3 patients in the LPLD group. Importantly, there were no major adverse cardiac and cerebrovascular events (MACCE) in either group.

Conclusion

A zero-fluoroscopy workflow utilizing an EAM system combined with ICE appears to be both feasible and safe for ablation in AF patients. In patients undergoing ICE-guided zero-fluoroscopy ablation, the HPSD strategy is comparable to LPLD ablation in effectiveness while offering the benefit of shorter procedure and ablation times.

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

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

Efficacy and safety of high-power short-duration ablation for atrial fibrillation: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

High-power short-duration (HPSD) ablation has emerged as an alternative to conventional standard-power long-duration (SPLD) ablation. We aim to assess the efficacy and safety of HPSD versus SPLD for atrial fibrillation (AF) ablation.

METHODS

A systematic review and meta-analysis of randomized controlled trials (RCTs) retrieved from PubMed, WOS, SCOPUS, EMBASE, and CENTRAL were performed through August 2023. We used RevMan V. 5.4 to pool dichotomous data using risk ratio (RR) and continuous data using mean difference (MD) with a 95% confidence interval (CI).

PROSPERO ID

CRD42023471797.

RESULTS

We included six RCTs with a total of 694 patients. HPSD was significantly associated with a decreased total procedure time (MD: -22.88 with 95% CI [-36.13, -9.63], P = 0.0007), pulmonary vein isolation (PVI) time (MD: -19.73 with 95% CI [-23.93, -15.53], P < 0.00001), radiofrequency time (MD: -10.53 with 95% CI [-12.87, -8.19], P < 0.00001). However, there was no significant difference between HPSD and SPLD ablation with respect to the fluoroscopy time (MD: -0.69 with 95% CI [-2.00, 0.62], P = 0.30), the incidence of esophageal lesions (RR: 1.15 with 95% CI [0.43, 3.07], P = 0.77), and the incidence of first pass isolation (RR: 0.98 with 95% CI [0.88, 1.08], P = 0.65).

CONCLUSION

HPSD ablation was significantly associated with decreased total procedure time, PVI time, and radiofrequency time compared with SPLD ablation. On the contrary, SPLD ablation was significantly associated with low maximum temperature.

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

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

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

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

General anesthesia enhances lesion quality and ablation efficiency of circumferential pulmonary vein isolation

Background

Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation. General anesthesia (GA) resolves the problem of pain intolerability and provides regular respiratory mode which might improve the catheter maneuverability of AF ablation. This study aims to compare the procedural performance of PVI under GA versus conscious sedation (CS) from multiple perspectives.

Methods

A total of 36 consecutive patients undergoing first AF ablation under GA were enrolled in GA group. Another 109 patients receiving AF ablation under CS in the same period were selected as the control group. After propensity score matching, 29 matched pairs with similar baseline characteristics were available for further analysis. The AIFV (using AI to analyze the raw data from CARTO3 system) system was used to evaluate six procedural parameters in each PVI procedure.

Results

Compared with CS, PVI under GA had a significantly shorter total PVI time (51.4 min vs. 67.8 min; p = .003) and higher radiofrequency ratio (62.6% vs. 55.8%; p = .032). The number of gaps (1.0 vs. 3.0; p < .001) and the rate of break point were significantly lower in the GA group. GA was also associated with a higher effective ablation-index ratio (87.5% vs. 74.1%; p < .001) and effective force-over-time ratio (85.3% vs. 69.2%; p = .001). After a medium follow-up time of 24 months, 12/29 (41.4%) patients in the CS group and 6/29 (20.7%) patients in the GA group suffered from AF recurrence (p = .156).

Conclusions

GA improves the lesion quality and procedural efficiency of PVI from multiple perspectives evaluated by the AIFV system.

Comparison of very high-power short-duration, high-power short-duration, and low-power long-duration radiofrequency ablation for atrial fibrillation: A systematic review and network meta-analysis

BACKGROUND

The optimal power and duration settings for radiofrequency (RF) atrial fibrillation (AF) ablation to improve efficacy and safety is unclear. We compared low-power long-duration (LPLD), high-power short-duration (HPSD), and very HPSD (vHPSD) RF settings for AF ablation.

METHODS

This network meta-analysis (NMA) was structured according to the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines. Medline, Scopus and Cochrane Central Register of Controlled Trials were systematically searched to identify relevant studies. Observational and randomized studies were included. Eligible studies compared outcomes in AF patients who underwent first-time RF ablation with the following settings: vHPSD (70-90 W, 3-10 s), HPSD (45-60 W, 5-10 s), or LPLD (20-40 W, 20-60 s).

RESULTS

Thirty-six studies comprising 10,375 patients were included (33% female). Frequentist NMA showed LPLD tended toward a lower odds of freedom from arrhythmia (FFA) versus HPSD (OR 0.93, 95% CI 0.86-1.00). There was no difference in FFA between vHPSD versus HPSD. Splitwise interval estimates showed a lower odds of FFA in LPLD versus vHPSD on direct (OR 0.78, 95% CI 0.65-0.93) and network estimates (OR 0.85, 95% CI 0.73-0.98). Frequentist NMA showed less total procedural (TP) time with HPSD versus LPLD (generic variance 1.06, 95% CI 0.83 to 1.29) and no difference between HPSD versus vHPSD.

CONCLUSION

This NMA shows improved procedural times in HPSD and vHPSD versus LPLD. Although HPSD tended toward improved odds of FFA compared to LPLD, the overall result was not statistically significant. The odds of FFA in LPLD was lower versus vHPSD on direct and network estimates on splitwise interval analysis. Large prospective head-to-head randomized trials are needed to validate HPSD and vHPSD settings.

50-W vs 40-W During High-Power Short-Duration Ablation for Paroxysmal Atrial Fibrillation: A Multicenter Prospective Study

BACKGROUND

High-power short-duration (HPSD) radiofrequency ablation of atrial fibrillation (AF) increases first-pass pulmonary vein isolation (PVI) and freedom from atrial arrhythmias while decreasing procedural time. However, the optimal power setting in terms of safety and efficacy has not been determined.

OBJECTIVES

This study compared the procedural characteristics and clinical outcomes of 50-W vs 40-W during HPSD ablation of paroxysmal AF.

METHODS

Patients from the REAL-AF prospective multicenter registry (Real-World Experience of Catheter Ablation for Treatment of Symptomatic Paroxysmal and Persistent Atrial Fibrillation) undergoing HPSD ablation of paroxysmal AF, either using 50-W or 40-W, were included. The primary efficacy outcome was freedom from all-atrial arrhythmias. The primary safety outcome was the occurrence of any procedural complication at 12 months. Secondary outcomes included procedural characteristics, AF-related symptoms, and the occurrence of transient ischemic attack or stroke at 12 months.

RESULTS

A total of 383 patients were included. Freedom from all-atrial arrhythmias at 12 months was 80.7% in the 50-W group and 77.3% in the 40-W group (Log-rank P = 0.387). The primary safety outcome occurred in 3.7% of patients in the 50-W group vs 2.8% in the 40-W group (P = 0.646). The 50-W group had a higher rate of first-pass PVI (82.3% vs 76.2%; P = 0.040) as well as shorter procedural (67 minutes [IQR: 54-87.5 minutes] vs 93 minutes [IQR: 80.5-111 minutes]; P < 0.001) and radiofrequency ablation times (15 minutes [IQR: 11.4-20 minutes] vs 27 minutes [IQR: 21.5-34.6 minutes]; P < 0.001) than the 40-W group.

CONCLUSIONS

There was no significant difference in freedom from all-atrial arrhythmias or procedural safety outcomes between 50-W and 40-W during HPSD ablation of paroxysmal AF. The use of 50-W was associated with a higher rate of first-pass PVI as well as shorter procedural times.

Index-Guided High-Power Radiofrequency Catheter Ablation for Atrial Fibrillation: A Systematic Review and Meta-Analysis Study

PURPOSE OF REVIEW

Studies have suggested the superiority of high-power compared to standard-power radiofrequency ablation ablation (RFCA). This study aimed to assess the efficacy and safety of high-power compared to standard-power RFCA guided by ablation index (AI) or lesion index (LSI).

RECENT FINDINGS

A systematic review and meta-analysis study comparing IGHP and IGLP approaches for AF ablation was conducted. The relevant published studies comparing IGHP and IGSP methods for RFCA in AF patients until October 2022 were collected from Cochrane, ProQuest, PubMed, and ScienceDirect. A total of 2579 AF patients from 11 studies were included, 1682 received IGHP RFCA, and 897 received IGSP RFCA. To achieve successful pulmonary vein isolation (PVI), the IGHP RFCA group had a significantly shorter procedure time than the IGHP RFCA group (mean difference (MD) -19.91 min; 95% CI -25.23 to -14.59 min; p < 0.01), radiofrequency (RF) application time (MD -10.92 min; 95% CI -14.70 to -7.13 min; p < 0.01), and fewer number of lesions (MD -10.90; 95% CI -18.77 to -3.02; p < 0.01) than the IGSP RFCA. First-pass PVI was significantly greater in the IGHP RFCA group than in the IGSP RFCA group (risk ratio (RR) 1.17; 95% CI 1.07 to 1.28; p < 0.01). The IGHP RFCA is an effective and efficient strategy for AF ablation. The superiority of IGHP RFCA includes the shorter procedure time, shorter RF application time, fewer number of lesions for complete PVI, and more excellent first-pass PVI.

Network meta-analysis and systematic review comparing efficacy and safety between very high power short duration, high power short duration, and conventional radiofrequency ablation of atrial fibrillation

BACKGROUND

High-power short-duration (HPSD) atrial fibrillation (AF) ablation with a power of 40-50 W was proved to be safe and effective. Very high-power short-duration (vHPSD) AF ablation is a novel method using >50 W to obtain more durable AF ablation. This study aimed to evaluate the efficacy and safety of vHPSD ablation compared with HPSD ablation and conventional power ablation.

METHODS

A literature search for studies that reported AF ablation outcomes, including short-term freedom from atrial arrhythmia, first-pass isolation (FPI) rate, procedure time, and major complications, was conducted utilizing MEDLINE, EMBASE, and Cochrane databases. All relevant studies were included in this analysis. A random-effects model of network meta-analysis and surface under cumulative ranking curve (SUCRA) were used to rank the treatment for all outcomes.

RESULTS

A total of 29 studies with 9721 patients were included in the analysis. According to the SUCRA analysis, HPSD ablation had the highest probability of maintaining sinus rhythm. Point estimation showed an odds ratio of 1.5 (95% confidence interval [CI]: 1.2-1.9) between HPSD ablation and conventional power ablation and an odds ratio of 1.3 (95% CI: 0.78-2.2) between vHPSD ablation and conventional power ablation. While the odds ratio of FPI between HPSD ablation and conventional power ablation was 3.6 (95% CI: 1.5-8.9), the odds ratio between vHPSD ablation and conventional power ablation was 2.2 (95% CI: 0.61-8.6). The procedure times of vHPSD and HPSD ablations were comparable and, therefore, shorter than that of conventional power ablation. Major complications were low in all techniques.

CONCLUSION

vHPSD ablation did not yield higher efficacy than HPSD ablation and conventional power ablation. With the safety concern, vHPSD ablation outcomes were comparable with those of other techniques.

Prevalence, Predictors and Mechanisms of Steam Pops in Ablation Index-Guided High-Power Pulmonary Vein Isolation

Despite the good cooling effect of the contact-force porous catheter, the risk of steam pops (SP) remains one of the major concerns in high-power circumferential pulmonary vein isolation (CPVI). This study aimed to investigate the prevalence, predictors and possible mechanisms of SPs in CPVI. Patients experiencing SPs in de novo high-power CPVI were 1:3 matched by non-SP patients with gender, age (±5 years) and left atrial diameter (LAD) (±5 mm) to compare the ablation parameters of SP and non-SP lesions. Catheter tip displacement (Tipdisp) was compared between “edge-of-ridge” and “PV-side-of-ridge” placement at anterior and roof segments of the left pulmonary vein (PV). SPs occurred in 11 (1.57%) of 701 patients, including 6 at the antero-superior left PV, 2 at the roof, 1 at the postero-superior left PV, 1 at the bottom left PV and 1 at the antero-superior aspect of the right PV. There was significantly shorter RF delivery duration (13.9 ± 6.3 vs. 23.3 ± 6.0 s), greater Δimpedance (17.6 ± 6.7 vs. 6.7 ± 4.1 Ω) and lower ablation index (357.7 ± 68.8 vs. 430.2 ± 30.7) in SP patients than those in non-SP patients. Δimpedance >12 Ω during ablation could predict SP occurrence. Tipdisp was greater in “PV-side-of-ridge” than that in “edge-of -ridge” placement (3.2 ± 1.6 mm vs. 2.0 ± 0.8 mm) at antero-superior and roof segments of the left PV. The prevalence of SP was 1.57% in high-power CPVI procedures, with the most common site at the antero-superior segment of the left PV. Δimpedance was a significant predictor of SP occurrence. “PV-side-of-ridge” ablation at antero-superior and roof segments of left PV might predispose to SP occurrence due to excessive tissue coverage.

Percutaneous Treatment Approaches in Atrial Fibrillation: Current Landscape and Future Perspectives

Atrial fibrillation (AF), the most common sustained arrhythmia in clinical practice, represents a major cause of morbidity and mortality, with an increasing prevalence. Pharmacologic treatment remains the cornerstone of its management through rhythm and rate control, as well as the prevention of thromboembolism with the use of oral anticoagulants. Recent progress in percutaneous interventional approaches have provided additional options in the therapeutic arsenal, however. The use of the different catheter ablation techniques can now lead to long arrhythmia-free intervals and significantly lower AF burden, thus reducing the rate of its complications. Particularly encouraging evidence is now available for patients with persistent AF or concomitant heart failure, situations in which catheter ablation could even be a first-line option. In the field of stroke prevention, targeting the left atrial appendage with percutaneous device implantation may reduce the risk of thromboembolism to lower rates than that predicted with conventional ischemic risk scores. Left atrial appendage occlusion through the approved Watchman or Amplatzer devices is a well-established, efficacious, and safe method, especially in high-ischemic and bleeding risk patients with contraindications for oral anticoagulation.

Esophageal safety in CLOSE-guided 50W high-power-short-duration pulmonary vein isolation - The PREHEAT-PVI-Registry

AIMS

Pulmonary vein isolation (PVI) using high-power-short-duration (HPSD) radiofrequency ablation (RF) is emerging as the standard of care for treatment of atrial fibrillation (AF). While procedural short-term to mid-term efficacy and efficiency are very promising, this registry aims to investigate esopahgeal safety using an optimized ablation approach.

METHODS

In a single-centre experience, 388 consecutive standardized first-time AF ablation were performed using a CLOSE-guided-fixed-50W-circumferential PVI and substrate modification without intraprocedural oesophageal temperature measurement. 300 patients underwent post-procedural esophageal endoscopy to diagnose and grade endoscopically detected esophageal lesions (EDEL) and were included in the analysis.

RESULTS

EDEL were detected in 35 of 300 patients (11.6%), 25 of 35 were low-grade KCC 1 lesions with fast healing tendencies. 6 patients suffered KCC 2a lesions, 4 patients had KCC 2b lesions (1.3% of all patients). No esophageal perforation or fistula formation was observed. Patient baseline characteristics, especially patients age, gender and body-mass-index did not influence EDEL incidence. Additional posterior box isolation did not increase the incidence of EDEL. In patients diagnosed with EDEL, mean catheter contact force during posterior wall ablation was higher (11.9 ± 1.8 vs. 14.7 ± 3 grams, p<0.001), mean RF duration was shorter (11.9 ± 1 vs. 10.7 ± 1.2 sec., p<0.001), while achieved AI was not different between groups (434 ± 4.9 vs. 433 ± 9.5, n.s.).

CONCLUSIONS

Incidence of EDEL after CLOSE-guided-50W-HPSD PVI is lower compared to historical cohorts using standard-power RF settings. Catheter contact force during posterior HPSD ablation should not exceed 15 grams. This article is protected by copyright. All rights reserved.

Comparison between High-Power Short-Duration and Conventional Ablation Strategy in Atrial Fibrillation: An Updated Meta-Analysis

High-power short-duration (HPSD) setting during radiofrequency ablation has become an attempt to improve atrial fibrillation (AF) treatment outcomes. This study ought to compare the efficacy, safety, and effectiveness between HPSD and conventional settings. PubMed, Embase, and Cochrane Library were searched. Studies that compared HPSD and conventional radiofrequency ablation settings in AF patients were included while studies performed additional ablations on nonpulmonary vein targets without clear recording were excluded. Data were pooled with random-effect model. Efficacy endpoints include first-pass pulmonary vein isolation (PVI), acute pulmonary vein (PV) reconnection, free from AF, and free from atrial tachycardia (AT) during follow-up. Safety endpoints include esophagus injury rate and major complication rate. Effectiveness endpoints include complete PVI rate, total procedure time, PVI time, and PVI radiofrequency ablation (PVI RF) time. We included 22 studies with 3867 atrial fibrillation patients in total (2393 patients received HPSD radiofrequency ablation). Perioperatively, the HPSD group showed a higher first-pass PVI rate (risk ratio, $\text{RR}=1.10$ , $P=0.0001$ ) and less acute PV reconnection rate ( $\text{RR}=0.56$ , $P=0.0004$ ) than the conventional group. During follow-up, free from AF ( $\text{RR}=1.11$ , $P=0.16$ ) or AT ( $\text{RR}=1.06$ , $P=0.24$ ) rate did not differ between HPSD and conventional groups 6-month postsurgery. However, the HPSD group showed both higher free from AF ( $\text{RR}=1.17$ , $P=0.0003$ ) and AT ( $\text{RR}=1.11$ , $P<0.0001$ ) rate than the conventional group 12-month postsurgery. The esophagus injury ( $\text{RR}=0.99$ , $P=0.98$ ) and major complications ( $\text{RR}=0.76$ , $P=0.70$ ) rates did not differ between the two groups. The HPSD group took shorter total procedure time ( $\text{MD}=-33.71$ 95% CI: -43.10 to -24.33, $P<0.00001$ ), PVI time ( $\text{MD}=-21.60$ 95% CI: -25.00 to -18.21, $P<0.00001$ ), and PVI RF time ( $\text{MD}=-13.72$ , 95% CI: -14.45 to -13.00, $P<0.00001$ ) than conventional groups while complete procedure rate did not differ between two groups ( $\text{RR}=1.00$ , $P=0.93$ ). HPSD setting during AF radiofrequency ablation has better effectiveness, efficacy, and similar safety compared with the conventional setting.

Reconnection patterns after high-power-short-duration pulmonary vein isolation Reconnection patterns after CLOSE-guided 50W high-power-short-duration circumferential pulmonary vein isolation and substrate modification - PV reconnection might no longer be an issue

INTRODUCTION

Ablation of atrial fibrillation (AF) with high-power-short-duration (HPSD) radiofrequency (RF) technology is emerging as a new standard of care in many electrophysiology laboratories. While procedural short-term efficacy and efficiency is very promising, little is known about mid- to long-term effects of HPSD ablation for pulmonary vein isolation and left atrial substrate modification.

METHODS AND RESULTS

In a single-centre registry, 412 AF procedures were performed in 400 individual patients using a standardized CLOSE protocol guided fixed 50W HPSD ablation, aiming for an ablation index (AI) of 400 on the posterior and 550 on the anterior wall. Additional substrate-tailored lines were performed when required. After a mean clinical follow-up of 337 ± 134 days, 15 patients suffered from AF recurrence beyond the blinding period. 12 gave consent to the indicated re-ablation. Here, 11 of 12 patients had chronic isolation of all 4 pulmonary veins (PV). In 3 of 6 patients, a reconnection of additional left atrial ablation lines was revealed. 10 out of 12 patients showed progressive fibrous atrial cardiomyopathy and required additional left atrial substrate modification or re-isolation of left-atrial lines. During the follow-up no clinical case of atrioesophageal fistula was registered. No PV stenosis after initial HPSD PVI was documented.

CONCLUSIONS

Patients requiring re-ablation of AF or other atrial tachycardia after a fixed 50W HPSD circumferential PVI and substrate modification predominantly suffer from progressive fibrous atrial cardiomyopathy, while PV reconnection appears to be a rare cause of AF recurrence. This article is protected by copyright. All rights reserved.