Outcomes of catheter ablation versus antiarrhythmic therapy in patients with atrial fibrillation: a systematic review and meta-analysis

Catheter ablation for atrial fibrillation and impact on clinical outcomes

Aims

Catheter ablation is the most effective rhythm-control option in patients with atrial fibrillation (AF) and is currently considered an option mainly for improving symptoms. We aimed to assess the impact of catheter ablation on hard clinical outcomes.

Methods and results

We performed a systematic review of randomized controlled trials (RCTs) comparing catheter ablation vs. optimized medical treatment. We searched MEDLINE, EMBASE, and CENTRAL on 8 January 2024, for trials published ≤10 years. We pooled data through risk ratio (RR) and mean differences (MDs), with 95% confidence interval (CI), and calculated the number needed to treat (NNT). Sub-group and sensitivity analyses were performed for the presence/absence of heart failure (HF), paroxysmal/persistent AF, early ablation, higher/lower quality, and published ≤5 vs. >5 years. Twenty-two RCTs were identified, including 6400 patients followed for 6-52 months. All primary endpoints were significantly reduced by catheter ablation vs. medical management: all-cause hospitalization (RR = 0.57, 95% CI 0.39-0.85, P = 0.006), AF relapse (RR = 0.48, 95% CI 0.39-0.58, P < 0.00001), and all-cause mortality (RR = 0.69, 95% CI 0.56-0.86, P = 0.0007, NNT = 44.7, driven by trials with HF patients). A benefit was also demonstrated for all secondary endpoints: cardiovascular mortality (RR = 0.55, 95% CI 0.34-0.87), cardiovascular (RR = 0.83, 95% CI 0.71-0.96), and HF hospitalizations (RR = 0.71, 95% CI 0.56-0.89), AF burden (MD = 20.6%, 95% CI 5.6-35.5), left ventricular ejection fraction (LVEF) recovery (MD = 5.7%, 95% CI 3.5-7.9), and quality of life (MLHFQ, AFEQT, and SF-36 scales).

Conclusion

Catheter ablation significantly reduced hospitalizations, AF burden, and relapse, and improved quality of life. An impact on hard clinical outcomes, with an important mortality reduction and improvement in LVEF, was seen for patients with AF and HF.

Pulsed Field Ablation of Atrial Fibrillation: An Initial Australian Single-Centre Experience

BACKGROUND

Pulsed field ablation (PFA) is a newer ablation energy source with the potential to reduce complications and improve efficacy compared to conventional thermal atrial fibrillation (AF) ablation. This study aimed to present an initial single-centre Australian experience of PFA for AF ablation.

METHODS

Initial consecutive patients undergoing PFA for paroxysmal or persistent AF at a single centre were included. Baseline patient characteristics, procedural data and clinical outcomes were collected prospectively at the time of the procedure. Patients were followed up at 3 months and 6-monthly thereafter.

RESULTS

In total, 100 PFA procedures were performed in 97 patients under general anaesthesia. All pulmonary veins (403 of 403) were successfully isolated acutely. Median follow-up was 218 days (range, 16-343 days), and the Kaplan-Meier estimate for freedom from atrial arrhythmias at 180 days was 87% (95% confidence interval 79%-95%). Median procedure time was 74 minutes (range, 48-134 minutes). Median fluoroscopy dose-area product was 345 μGym2 (interquartile range, 169-685 μGym2). Two (2%) pseudoaneurysm vascular access complications occurred. There were no cases of thromboembolic complications, stroke, phrenic nerve palsy, pulmonary vein stenosis, atrio-oesophageal fistula, or pericardial tamponade.

CONCLUSIONS

Pulsed field ablation can be performed safely and efficiently, with encouraging efficacy in early follow-up. Further data and clinical trials will be required to assess the comparative utility of PFA in contemporary AF ablation practice.

Freedom from atrial arrhythmia and other clinical outcomes at 5 years and beyond after catheter ablation of atrial fibrillation: a systematic review and meta-analysis

AIMS

Catheter ablation of atrial fibrillation (AF) is now a mainstream procedure although long-term outcomes are uncertain. We performed a systematic review and meta-analysis of procedural outcomes at 5 years and beyond.

METHODS AND RESULTS

We searched PubMed and Embase and after the screening, identified 73 studies (67 159 patients) reporting freedom from atrial arrhythmia, all-cause death, stroke, and major bleeding at ≥5 years after AF ablation. The pooled mean age was 59.7y, 71.5% male, 62.2% paroxysmal AF, and radiofrequency was used in 78.1% of studies. Pooled incidence of freedom from atrial arrhythmia at 5 years was 50.6% (95%CI 45.5-55.7%) after a single ablation and 69.7% [95%CI (confidence interval) 63.8-75.3%) after multiple procedures. The incidence was higher among patients with paroxysmal compared with non-paroxysmal AF after single (59.7% vs. 33.3%, p = 0.002) and multiple (80.8% vs. 60.6%, p < 0.001) ablations but was comparable between radiofrequency and cryoablation. Pooled incidences of other outcomes were 6.0% (95%CI 3.2-9.7%) for death, 2.4% (95%CI 1.4-3.7%) for stroke, and 1.2% (95%CI 0.8-2.0%) for major bleeding at 5 years. Beyond 5 years, freedom from arrhythmia recurrence remained largely stable (52.3% and 64.7% after single and multiple procedures at 10 years), while the risk of stroke and bleeding increased over time.

CONCLUSION

Nearly 70% of patients having multiple ablations remained free from atrial arrhythmia at 5 years, with the incidence slightly decreasing beyond this period. Risk of death, stroke, and major bleeding at 5 years were low but increased over time, emphasizing the importance of long-term thromboembolism prevention and bleeding risk management.

Ganglionic Plexus Ablation: A Step-by-step Guide for Electrophysiologists and Review of Modalities for Neuromodulation for the Management of Atrial Fibrillation

As the most common sustained arrhythmia, AF is a complex clinical entity which remains a difficult condition to durably treat in the majority of patients. Over the past few decades, the management of AF has focused mainly on pulmonary vein triggers for its initiation and perpetuation. It is well known that the autonomic nervous system (ANS) has a significant role in the milieu predisposing to the triggers, perpetuators and substrate for AF. Neuromodulation of ANS - ganglionated plexus ablation, vein of Marshall ethanol infusion, transcutaneous tragal stimulation, renal nerve denervation, stellate ganglion block and baroreceptor stimulation - constitute an emerging therapeutic approach for AF. The purpose of this review is to summarise and critically appraise the currently available evidence for neuromodulation modalities in AF.