Efficacy of Catheter Ablation for Persistent Atrial Fibrillation: A Systematic Review and Meta-Analysis of Evidence from Randomised and Non-Randomised Controlled Trials
Background—Catheter ablation (CA) is commonly performed for persistent atrial fibrillation (PeAF) but few high-quality randomised controlled trials (RCTs) exist; leading to funding restrictions being proposed in several countries. We performed a random-effects meta-analysis of RCTs and non-RCTs (NRCTs) to assess the efficacy of CA for PeAF.
Methods and Results—We systematically searched PubMed, EMBASE, CENTRAL, OpenGrey and clinicaltrials.gov for RCTs and NRCTs reporting clinical outcomes after CA for PeAF. 46 studies eligible studies were identified containing 3819 patients. After a single procedure CA significantly reduced the risk of recurrent AF compared to medical therapy (OR 0.32, 95%CI 0.20-0.53, p<0.001). Outcomes were better if the pulmonary veins (PVs) were encircled (OR 0.26, 95%CI 0.09-0.74, p=0.01) and electrical isolation produced better outcomes than purely anatomical encirclement (OR 0.33, 95%CI 0.13-0.86, p=0.02). Linear ablation within the left atrium (LA) (OR 0.22, 95%CI 0.10-0.49, p<0.001), but not CFAE ablation (OR 0.64, 95%CI 0.35-1.18, p=0.15), significantly improved outcomes. Results were not improved by performing more extensive linear lesion sets (OR 0.77, 95%CI 0.41-1.43, p=0.40) or from bi-atrial ablation (OR 0.62, 95%CI 0.31-1.24, p=0.17). Where data were available, the relative benefits seen held true both after a single or multiple procedure(s). Sensitivity analyses showed that inclusion of NRCTs increased statistical power without biasing the calculated effect sizes.
Conclusions—For patients with PeAF, CA achieves significantly greater freedom from recurrent AF than medical therapy. The most efficacious strategy is likely to combine isolation of the PVs with limited linear ablation within the LA.
- Received March 2, 2014.
- Revision received July 2, 2014.
- Accepted July 7, 2014.