Experts recommend shortening the blanking time after atrial fibrillation ablation

Experts recommend shortening the blanking time after atrial fibrillation ablation

New evidence-based research challenges the traditional three-month blanking period immediately following atrial fibrillation (AF) ablation, assuming that early onset of AF is not indicative of long-term recurrence of AF. Two articles and an accompanying editorial inheart rhythmthe official journal of the Heart Rhythm Society, the Cardiac Electrophysiology Society and the Pediatric & Congenital Electrophysiology Society, published by Elsevier, addresses the controversy and recommends shortening the blanking period.

Early recurrence of atrial tachyarrhythmia (ERAT) is commonly observed after catheter ablation of atrial fibrillation, with an incidence as high as 61% in the first three months. ERAT is often attributed to transient inflammation caused by tissue damage during ablation and short-term imbalances in autonomic innervation. This forms the physiological rationale for the accepted convention of a three-month blanking period, during which recurrent arrhythmias are assumed to be relatively benign and do not indicate treatment failure. However, this reasoning ignores valuable data on early recurrence of arrhythmias and their potential significance.

The authors of the editorial on the two articles inheart rhythmare calling for the three-month embargo period to be reconsidered and suggest that perhaps it is time to scrap the embargo period altogether. Lead author Jonathan M. Kalman, MBBS, PhD, from the Department of Cardiology, Royal Melbourne Hospital, Australia, says:"Given increasing data suggesting that early recurrence of atrial fibrillation is a predictor of late recurrence, the three-month blanking period has been questioned. Although clinical trials evaluating atrial fibrillation ablation have traditionally defined treatment success by time to first recurrence of atrial fibrillation, the use of such a binary efficacy outcome is lacking." on clinical basis and it represents an oversimplification of the effect of ablative therapy.”

Lead author of the article “Defining the Blanking Period Using Continuous ECG Monitoring After Cryoballoon Pulmonary Vein Isolation,”“Dan Musat, MD, of Valley Hospital and the Snyder Center for Comprehensive Atrial Fibrillation, Ridgewood, NJ, USA, states:“MSeveral studies have questioned the length of the blanking period. Our study used continuous monitoring and showed that both the timing of the last ERAT episode and the exposure to ERAT provided consistent results; Any ERAT after the first month indicates a worse outcome. Our data show that approximately one-third of patients who experience ERAT and/or have burden >0% after the first month after cryoballoon pulmonary vein isolation are at significantly higher risk of long-term recurrent atrial fibrillation. These findings lead us to consider changing the length of the blanking period after atrial fibrillation ablation from the current three months to one month.”

Co-author Suneet Mittal, MD, from Valley Hospital and the Snyder Center for Comprehensive Atrial Fibrillation, Ridgewood, NJ, USA, adds:“Our results also demonstrate the value of continuous long-term ECG monitoring, as information about the presence and burden of atrial fibrillation can help inform clinical decision-making in patients following pulmonary vein isolation by cryoballoon.”

In “Early recurrence of atrial fibrillation after catheter ablation: analysis of an insertable cardiac monitor in the era of optimized radiofrequency ablation,” De Becker et al. also emphasize the importance of continuous monitoring. They compiled data from the Close-To-Cure and Close Maze trials, which included 165 patients who underwent radiofrequency (RF) ablation for paroxysmal or persistent atrial fibrillation. All patients had an insertable cardiac monitor implanted two to three months before ablation. The study found that patients with ERAT had a significantly higher risk of late recurrence and exposure to ERAT during the blanking period was a significant predictor.

Lead researcher Benjamin De Becker, MD, from the Department of Cardiology, AZ Sint Jan, Bruges, Belgium explains:"During the blanking period, ERAT burden and ERAT occurring in the third month are independently associated with late recurrence. ERAT occurring 64 days after ablation was associated with a very high risk of late recurrence in both paroxysmal and persistent atrial fibrillation patients, suggesting this." The traditional blanking period could be shortened after AF ablation to avoid unnecessary ablation due to procedure-related arrhythmogenicity and to avoid the occurrence of subsequent repermeabilization of the RF lesions, which could require further reablation, so a two-month blanking period after ablation would be an acceptable compromise to reduce the risk of unnecessary Minimize repetition of the procedure. After this two-month period, the occurrence of atrial tachyarrhythmia is highly predictive of subsequent relapses.

Professor Kalman concludes:"In light of these new findings, a more stringent interpretation of the results of these studies might be that the notion of a blanking period itself should be reconsidered. We believe that these data support a recommendation to eliminate the blanking period."

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