The effect of second-generation cryoablation without electrical mapping in persistent AF using continuous monitoring

A retrospective analysis of frailty status on atrial fibrillation catheter ablation outcomes

INTRODUCTION

Catheter ablation for atrial fibrillation (AF) reduces symptoms and improves the quality of life compared with medical treatment. It is unclear if frailty impacts on the outcome of catheter ablation in patients with symptomatic AF. We sought to evaluate the association between frailty as measured by the validated NHS electronic Frailty Index (eFI) and outcomes post-AF ablation.

METHODS

Two hundred forty eight patients who had undergone AF ablation with a mean age of 72.9 ± 5.16 were included in the study retrospectively. The primary endpoint for success was defined as freedom from atrial arrhythmia lasting >30 s beyond the 3-month blanking periods. Frailty was based on the eFI, and the cohort split into four groups: fit (no frailty), mild, moderate and severe frailty.

RESULTS

Frailty was categorized as fit (118/248; 47.6%), mild (66/248; 26.6%), moderate (54/248; 21.8%), and severe (10/248; 4.0%). Freedom from arrhythmia occurred in 167 of 248 (67.3%) patients after a mean follow-up of 25.8 +/- 17.3 months. Fit patients had significantly greater freedom from arrhythmia (92/118; 78%) compared to mild frailty (40/66; 60.6%, p-value = .020), moderate frailty (31/54; 57.4%, p-value = .006), or severe frailty (4/10; 40.0%, p-value < .001). There was also a significant difference in arrhythmia occurrence between patients with mild frailty and severe frailty (p-value = .044).

CONCLUSION

Frailty is associated with poorer outcomes in patients undergoing AF ablation. The eFI may be used in the prognostic evaluation of AF ablation outcomes. Further studies are essential to confirm the findings of this study.

Innovations in atrial fibrillation ablation

BACKGROUND

Catheter-based ablation to perform pulmonary vein isolation (PVI) has established itself as a mainstay in the rhythm control strategy of atrial fibrillation. This review article aims to provide an overview of recent advances in atrial fibrillation ablation technology.

METHODS

We reviewed the available literature and clinical trials of innovations in atrial fibrillation ablation technologies including ablation catheter designs, alternative energy sources, esophageal protection methods, electroanatomical mapping, and novel ablation targets.

RESULTS

Innovative radiofrequency (RF) catheter designs maximize energy delivery while avoiding overheating associated with conventional catheters. Single-shot balloon catheters in the form of cryoballoons, radiofrequency, and laser balloons have proven effective at producing pulmonary vein isolation and improving procedural efficiency and reproducibility. Pulsed field ablation (PFA) is a highly anticipated novel nonthermal energy source under development, which demonstrates selective ablation of the myocardium, producing durable lesions while also minimizing collateral damage. Innovative devices for esophageal protection including esophageal deviation and cooling devices have been developed to reduce esophageal complications. Improved electroanatomical mapping systems are being developed to help identify additional non-pulmonary triggers, which may benefit from ablation, especially with persistent atrial fibrillation. Lastly, the vein of Marshall alcohol ablation has been recently studied as an adjunct therapy for improving outcomes with catheter ablation for persistent atrial fibrillation.

CONCLUSIONS

Numerous advances have been made in the field of atrial fibrillation ablation in the past decade. While further long-term data is still needed for these novel technologies, they show potential to improve procedural efficacy and safety.

The long-term effect of thermal-guided second-generation cryoablation in paroxysmal and persistent atrial fibrillation

BACKGROUND

Second-generation cryoballoon ablation is safe and effective in patients with paroxysmal (PAF) and persistent atrial fibrillation (AF).

OBJECTIVE

This study aimed to assess the long-term clinical outcomes and freedom from AF in patients undergoing thermal-guided cryoablation without the use of an electrical mapping catheter.

METHODS

All patients who had undergone thermal-guided second-generation cryoablation without electrical mapping between January 2015 and April 2018 at Eastbourne District General Hospital were retrospectively analysed. Success was defined as freedom from atrial arrhythmia lasting >30 s during the follow up period.

RESULTS

The study included 234 patients with a mean age of 65.3 ± 10.6 years. There were 134 (57.0%) and 100 (42.7%) patients who had PAF and persistent AF respectively. Arrhythmia recurrence occurred in 38 of 134 (28.4%) PAF and 42 of 100 (42.0%) persistent AF patients after mean follow up of 40 ± 9.2 months. The patients with PAF had a significantly greater freedom from arrhythmia than patients with persistent AF (p = .040). The mean procedure time was 55.5 ± 12.2 min and the mean fluoroscopy time was 10.9 ± 4.8 min 73.5% of patients were discharged on the same day.

CONCLUSION

Thermal-guided cryoablation is feasible, safe and results in freedom from arrhythmia in the majority of paroxysmal and persistent AF patients in the long term. Randomised controlled trials are required to confirm the findings of this study.