Atrial fibrillation recurrences during the blanking period after catheter ablation with the laser balloon technique

Rethinking appropriate blanking period after atrial fibrillation ablation

BACKGROUND

Early recurrence (ER) within a 90-day blanking period (BP) in catheter ablation (CA) for atrial fibrillation (AF) is a risk factor for late recurrence (LR) after 90 days postoperatively. However, few reports have examined them in the second CA and compared them to the first CA. Moreover, in recent years, there have been reports suggesting that BP should be reduced from 90 to 30 days. Therefore, the association between ER and LR in the first and the second CA was examined, and the validity of a 30-day BP was evaluated.

METHODS

A total of 511 consecutive patients undergoing the first CA and 116 of these patients undergoing the second CA for AF at a single institution from November 2016 to December 2020 were analyzed retrospectively.

RESULTS

When ER within a 90-day BP was divided into 0-30 days and 31-90 days according to the timing of the last ER episode, the hazard ratios on LR of them relative to no ER were 2.7 {95% confidence interval (CI) 1.7-4.2} and 9.7 (95% CI 6.6-14.3), respectively, for the first CA and 15.3 (95% CI 4.7-50.1) and 44.1 (95% CI 14.0-139.4), respectively, for the second CA.

CONCLUSIONS

ER was strongly associated with LR, especially in patients with the last episode of ER more than 30 days after CA. This was pronounced in cases after the second CA, when PVI appeared to be completed. With the current improvement in PVI durability, BP may be acceptable for 30 days.

Redefining the blanking period after pulsed-field ablation in patients with atrial fibrillation

BACKGROUND

Recurrence during the 3-month blanking period after radiofrequency ablation of atrial fibrillation (AF) is typically not considered as a predictor for late recurrence.

OBJECTIVE

We investigated the significance of early recurrence as a risk factor for late recurrence in patients with AF receiving pulsed-field ablation (PFA).

METHODS

Consecutive patients undergoing PFA were prospectively followed up for 1 year. All patients received isolation of pulmonary veins. Additional ablation procedures were performed per operator's discretion. After the procedure, all remained on their previously ineffective antiarrhythmic drugs (AADs) during the 2-month blanking period after which the AADs were discontinued. Early recurrence was defined as atrial arrhythmia of >30-second duration during the 3-month blanking period, and any recurrence beyond 3 months was considered as late recurrence.

RESULTS

A total of 337 patients undergoing PFA for AF were included. Early recurrence was recorded in 53 patients (15.7%): 10 in the first month, 12 in the second month, and 31 in the third month. Of the 10 patients having recurrence during the first month, 7 (70%) remained in sinus rhythm after cardioversion whereas 3 (30%) underwent a redo procedure because of late recurrence. At 1 year, all patients with recurrence in the second and third months experienced late recurrence; among these patients, 10 (83.3%) of 12 and 27 (87%) of 31 underwent a redo procedure and the remaining 6 patients were in sinus rhythm on AADs.

CONCLUSION

In this consecutive series of patients with AF, early recurrence in the second or third month after the PFA procedure was associated with a high risk of late recurrence. Thus, blanking period could be redefined as 1 month after PFA.

Defining the blanking period, using continuous ECG monitoring, after cryoballoon pulmonary vein isolation

BACKGROUND

Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation. A blanking period (BP) of 3 months is used in clinical trials and practice. However, the optimal BP duration after PVI remains undefined.

OBJECTIVE

The aim of this study was to objectively define, using continuous monitoring by an implantable loop recorder, the optimal BP duration after cryoballoon PVI.

METHODS

We enrolled consecutive patients who had cryoballoon PVI and an implantable loop recorder. We determined the time of the last confirmed episode of AF within the blanking period. This was then correlated with AF recurrence in the first year after ablation.

RESULTS

There were 210 patients (66 ± 9 years; 138 [66%] male; 116 [55%] paroxysmal AF; CHA2DS2-VASc score, 2.5 ± 1.6). We defined 4 distinct groups based on the last AF episode within the BP: no AF days 0-90 (n = 96 [46%]) and last AF 0-30 days (n = 46 [22%]), 31-60 days (n = 18 [9%]), and 61-90 days (n = 50 [24%]). After the 3-month BP, 101 (48%) patients had AF recurrence at 160 ± 86 days. Compared with patients with no AF in the BP, those with recurrent AF and AF burden >0% 30 days after ablation had a significantly greater AF recurrence during long-term follow-up (P = .001).

CONCLUSION

Our data show that the approximately one-third of patients in whom AF occurs and who have a burden of >0% after the first month that follows PVI are at significantly higher risk of long-term recurrent AF. We therefore suggest that the blanking period be limited to a month after cryoballoon PVI.