The blanking interval after atrial fibrillation ablation: time for reassessment with pulsed field energy.

Early recurrences within 30, 60, and 90 days post-PFA were all significantly associated with late recurrences beyond 90 days.

• 30-day threshold: HR 5.9, 95% CI 4.4–7.9, P < 0.01
• 60-day threshold: HR 6.6, 95% CI 5.0–8.6, P < 0.01
• 90-day threshold: HR 9.1, 95% CI 7.0–11.7, P < 0.01
• Analyses performed using Kaplan-Meier and multivariate Cox regression
• Total cohort of 1162 consecutive patients who underwent PFA for AF across multiple Mayo Clinic health system centres

The estimated AF-free survival at 1 year following PFA was 70%.

• Primary endpoint was AF-free survival
• Sample size was 1162 patients
• Patients were consecutive and drawn from multiple centres within the Mayo Clinic health system

Among patients undergoing continuous rhythm monitoring, early recurrences within 30 days were significantly associated with a 1-year AF burden >1% or the need for repeat AF ablation.

• Odds ratio 25.0, 95% CI: 6.6–126.8, P < 0.01
• This subgroup analysis was limited to patients with continuous rhythm monitoring
• The outcome composite included AF burden >1% at 1 year or need for repeat AF ablation

The association between early recurrences and late recurrences remained significant among patients undergoing continuous rhythm monitoring.

• Findings were consistent across all three blanking period thresholds (30, 60, and 90 days) in this subgroup
• Continuous rhythm monitoring represents a more rigorous ascertainment method for early recurrences compared to intermittent monitoring

The study concluded that early recurrences following PFA are unlikely to represent transient inflammatory phenomena, in contrast to the assumption underlying the conventional blanking interval.

• The conventional 90-day blanking interval was originally established based on the premise that early recurrences after thermal ablation may reflect transient inflammation
• The strong predictive association of even 30-day recurrences with long-term outcomes challenges the applicability of this concept after PFA
• Authors state the 'applicability of the conventional blanking interval after PFA should be reconsidered'