Current Status of Atrial Fibrillation Ablation with Balloon Strategy

Acute and long-term results with the 3rd generation visually guided laser balloon ablation system for pv isolation

BACKGROUND

Visually guided laser balloon ablation is known as an effective pulmonary vein (PV) isolation device. The third-generation laser balloon ablation system (X3) equipped with compliant balloon and an automated motor-driven laser output mechanism, namely RAPID mode, has been clinically proven for PV isolation.

METHODS

PV isolation with X3 was performed in all the patients with paroxysmal and early-stage persistent atrial fibrillation (AF). Acute data for PV isolation and clinical outcomes including supraventricular tachyarrhythmia (SVT: AF, atrial flutter, or atrial tachycardia)-free survival rate beyond 1 year were analyzed.

RESULTS

A total of 110 patients (62 ± 13 years old, 80% of paroxysmal AF) were treated with X3. RAPID mode with was utilized to achieve PV isolation in all cases. In combination with RAPID mode and spot mode laser ablation, 91.1% (380/417) of veins were isolated on the first circumferential lesion set and did not require touch-up ablation and during the index procedure 100% of attempted veins were isolated. The mean procedure time was 77.0 ± 22.7 min and LA dwell time was 61.9 ± 22.0 min. Total duration of laser application was 5.1 ± 2.3 min per vein. At 1 year, SVT-free survival rate was 93.7% in paroxysmal AF patients, and 81.1% in persistent AF patients.

CONCLUSIONS

A novel continuous automatic laser balloon ablation system was proved to be safe and effective for both paroxysmal and persistent AF patients. The clinical result demonstrated that PV isolation with X3 could achieve a high SVT-free survival rate.

Cryoballoon vs. laser balloon ablation for atrial fibrillation: a meta-analysis

Background

Cryoballoon ablation (CBA) and laser balloon ablation (LBA) are two innovative ways for the treatment of atrial fibrillation (AF). This study aimed to evaluate the efficacy and safety of cryoballoon ablation and laser balloon ablation in patients with AF.

Methods

We searched Pubmed, Embase, Ovid, Web of Science and other databases for comparative trials comparing CB and LB ablation in the treatment of AF, from establishment of database to August, 2023.

Results

A total of 13 studies and 3,582 patients were included (CBA, n = 2,308; LBA, n = 1,274). There was no difference between CBA and LBA in acute PVI rate per vein, 12-months recurrence rate of AF, 12-months recurrence rate of atrial arrhythmia, occurrence rate of pericardial tamponade, occurrence rate of inguinal complications. LBA presented a lower acute PVI rate per patients (CBA 97.0% vs. LBA 93.4%, RR = 1.04, 95%CI: 1.01-1.07). Transient nerve palsy was more likely to occur after CBA (CBA 2.7% vs. LBA 0.7%, RR = 4.25, 95%CI: 2.06-8.76). However, the occurrence of persistent nerve palsy between CBA and LBA groups were similar (CB 1.4% vs. LB 1.0%, RR = 1.09, 95%CI: 0.55-2.14). In terms of procedural duration, the procedural time of CBA was shorter than that of LBA (WMD = -26.58, 95%CI: -36.71-16.46).

Conclusions

Compared with LBA, CBA had a shorter procedural duration. There was a higher incidence of transient but not persistent phrenic nerve palsy after CBA.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=272607 Identifier (CRD42021272607).

Initial clinical experience of pulmonary vein isolation using the ultra-low temperature cryoablation catheter for patients with atrial fibrillation

BACKGROUND

The iCLAS ultra-low temperature cryoablation (ULTC) system has recently brought to the market. A combination of a newly exploited cryogen and interchangeable stylet enables flexible and continuous lesion creation in atrial fibrillation (AF) ablation. The use of an esophageal warming balloon is recommended when using the system to reduce the potential for collateral esophageal injury.

OBJECTIVE

To describe the initial clinical experience when using ULTC in the AF treatment without general anesthesia (GA).

METHODS

Consecutive patients undergoing AF ablation using ULTC under deep sedation without GA were enrolled. We assessed the procedural data focusing on "single-shot isolation" defined as successful pulmonary vein (PV) isolation after the first application. Esophagogastroduodenoscopy was systematically performed the day after ablation.

RESULTS

A total of 27 AF patients (67% paroxysmal AF) were analyzed. One-hundred-four out of 106 PVs (98.1%) were isolated solely using ULTC. The mean procedure time was 79 ± 30 min. The mean number of applications per PV was 2.6 ± 1.0. Single-shot isolation was achieved in 57 PVs (54%) varying across PVs from left superior- to inferior PVs (40-64%). Single procedure six-month recurrence free rate was 84%. No major complication (cerebrovascular event, pericardial effusion/tamponade, esophageal damage on esophagogastroduodenoscopy) occurred. A single transient phrenic nerve palsy occurred during the right superior PV ablation which had recovered by the 3-month follow up appointment.

CONCLUSIONS

AF ablation using the novel ULTC system seemed feasible without GA and enabled >50% single-shot isolation rate. The promising safety profile has to be confirmed in large-scaled studies. This article is protected by copyright. All rights reserved.

Shorter RSPV cryoapplications result in less phrenic nerve injury and similar 1-year freedom from atrial fibrillation

BACKGROUND

In the 123-study, we prospectively assessed, in a randomized fashion, the minimal cryoballoon application time necessary to achieve pulmonary vein (PV) isolation (PVI) in patients with paroxysmal atrial fibrillation (AF) with the aim to reduce complications by shortening the application duration. The first results of this study demonstrated that shortened cryoballoon applications (<2 minutes) resulted in less phrenic nerve injury (PNI) without compromising acute isolation efficacy for the right PVs. We now report the 1-year follow-up results regarding safety and efficacy of shorter cryoballoon applications.

METHODS

A total of 222 patients with AF were randomized to two applications of 1 min "short," 2 min "medium," or 3 min "long" duration, 74 per group. Recurrence of AF and PV reconduction at 1-year follow-up were assessed.

RESULTS

The overall 1-year freedom from AF was 79% and did not differ significantly between the short, medium, and long application groups (77%, 74%, and 85% for short, medium, and long application groups, respectively; P = 0.07). In 30 patients, a redo PVI procedure was performed. For all four PVs, there was no significant difference in reconduction between the three groups. Reconduction was most common in the left superior PV (57%). The right superior PV (RSPV) showed significantly less reconduction (17%) compared to the other PVs.

CONCLUSIONS

Shortening cryoballoon applications of the RSPV to <2 minutes results in less PNI, while acute success and 1-year freedom from AF are not compromised. Therefore, shorter cryoballoon applications (especially) in the RSPV could be used to reduce PNI.

Esophageal injury associated with catheter ablation for atrial fibrillation: Determinants of risk and protective strategies

Catheter ablation has become an important element in the management of atrial fibrillation. Several technical advances allowed for better safety profiles and lower recurrence rates, leading to an increasing number of ablations worldwide. Despite that, major complications are still reported, and esophageal thermal injury remains a significant concern as atrioesophageal fistula (AEF) is often fatal. Recognition of the mechanisms involved in the process of esophageal lesion formation and the identification of the main determinants of risk have set the grounds for the development and improvement of different esophageal protective strategies. More sensitive esophageal temperature monitoring, safer ablation parameters and catheters, and different energy sources appear to collectively reduce the risk of esophageal thermal injury. Adjunctive measures such as the prophylactic use of proton-pump inhibitors, as well as esophageal cooling or deviation devices, have emerged as complementary methods with variable but promising results. Nevertheless, as a multifactorial problem, no single esophageal protective measure has proven to be sufficiently effective to eliminate the risk, and further investigation is still warranted. Early screening in the patients at risk and prompt intervention in the cases of AEF are important risk modifiers and yield better outcomes.