Pulsed-Field Ablation of Atrial Flutter: Insights From a Large Volume U.S. Center.

Background: Pulsed-field ablation (PFA) is increasingly used in clinical practice for atrial fibrillation, but its utility in atrial flutter (AFL) ablation is not yet established.

Objectives: This study sought to evaluate the safety, effectiveness, and procedural outcomes of PFA in treating AFL across different subtypes.

Methods: This study included 311 consecutive patients undergoing ablation of 368 AFLs using PFA. All flutters were ablated with emphasis on intracardiac echocardiography guidance. Acute procedural success (defined as either AFL termination or bidirectional block across ablation lines), recurrence rates, and safety outcomes were prospectively assessed. AFL recurrence was evaluated after a 90-day blanking period.

Results: All targeted AFL circuits were successfully ablated. When using PFA alone, acute procedural success was 96.5% (95% CI: 94.03%-98.11%), with rates of 99.5% (95% CI: 97.34%-99.99%) for cavotricuspid isthmus-dependent flutters and 85.4% (95% CI: 75.83%-92.20%) for perimitral circuits. Adjunctive radiofrequency ablation was required in 3.5% of circuits, predominantly perimitral AFLs. Freedom from procedure-related adverse events was observed in 99% of cases (95% CI: 97.21%-99.80%). Over a median follow-up of 175 days (Q1-Q3: 132-244 days), AFL recurrence was observed in 14 flutters (3.9%; 95% CI: 2.17%-6.53%), with success rates of 98.5% for cavotricuspid isthmus-dependent flutters and 90% for perimitral AFLs.

Conclusions: PFA is a safe and effective modality for AFL ablation, achieving high acute success rates and favorable safety outcomes.