Repeat in situ ablation vs. extensive ablation for recurrent persistent atrial fibrillation

Area of Science:

• Cardiology
• Electrophysiology
• Medical Devices

Background:

• Repeat ablation strategies for persistent atrial fibrillation (PerAF) are less studied than initial procedures.
• The efficacy of repeat ablation, especially extensive extra-pulmonary vein (PV) ablation versus in situ ablation, requires further investigation.

Purpose of the Study:

• To compare the efficacy of repeat extra-PV extensive ablation (EXT) versus repeat PV isolation (PVI) and linear ablation (in situ) in patients with recurrent PerAF.
• To assess the impact of ablation strategy on freedom from atrial fibrillation (AF)/atrial tachycardia (AT) recurrence and safety outcomes.

Main Methods:

• A randomized controlled trial comparing EXT (n=66) and in situ (n=66) ablation strategies for recurrent PerAF.
• The primary endpoint was freedom from AF/AT episodes >30 seconds at 12 months.
• Safety endpoints were also monitored and compared between groups.

Main Results:

• The EXT group showed a significantly higher rate of freedom from AF/AT recurrence at 12 months (66.7%) compared to the in situ group (48.5%) (P=0.037).
• Freedom from AF recurrence was also significantly higher in the EXT group (77.3%) versus the in situ group (60.6%) (P=0.027).
• No significant differences in safety endpoints were observed between the two groups (4.5% vs. 6.1%, P=0.716).

Conclusions:

• Extensive extra-PV ablation demonstrates superior clinical efficacy for repeat ablation in PerAF patients compared to repeat PV isolation and linear ablation.
• These findings suggest that targeting additional non-PV substrates improves outcomes, indicating that PV reconnection and linear lesion reconduction may not be the sole drivers of AF recurrence.