Gaps after linear ablation of persistent atrial fibrillation (Marshall-PLAN): Clinical implication

Area of Science:

• Electrophysiology
• Cardiac Ablation
• Atrial Fibrillation Management

Background:

• Anatomic isthmus transection is an adjunctive strategy for persistent atrial fibrillation, complementing pulmonary vein (PV) isolation.
• Data on the durability and impact of gaps within these complex lesion sets are limited.

Purpose of the Study:

• To evaluate the impact of gaps within the lesion set of pulmonary vein isolation and isthmus transection for persistent atrial fibrillation.
• To assess the durability of multiple lines of block and the effect of gap closure on outcomes.

Main Methods:

• A consecutive cohort of 291 patients underwent vein of Marshall ethanol infusion, PV isolation, and mitral, cavotricuspid, and dome isthmus transection.
• Dome isthmus transection utilized two strategies: a single roof line or an alternative floor line based on high-density mapping to identify and address gaps.

Main Results:

• Twelve-month sinus rhythm maintenance was 70% after one procedure and 94% after repeat procedures. Residual gaps significantly lowered event-free survival (P = .004).
• Delayed gaps were common in patients experiencing recurrence, with PV gaps increasing atrial fibrillation recurrence risk (67% vs 34%; P = .02) and isthmus gaps associated with atrial tachycardias (60%).
• The second strategy, involving a floor line if roof lines showed gaps, significantly reduced delayed dome gaps (43% vs 68%; P = .05).

Conclusions:

• Gaps within ablation lines are arrhythmogenic and negatively impact outcomes in persistent atrial fibrillation treatment.
• Optimized ablation techniques and thorough assessment to minimize and close gaps are crucial for improving sinus rhythm maintenance and reducing recurrence.