Efficacy and safety of left atrial appendage isolation in addition to pulmonary vein isolation in atrial fibrillation cryoballoon ablation
Authors: Esteve Ruiz I , Moraleda Salas MT , Arce Leon A , Fernandez Gomez JM , Venegas Gamero J , Morina Vazquez P 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
Although pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation, the percentage of patients in which a recurrence is detected is still high. This concern has increased the interest in finding new ablation techniques that could diminish recurrences.

Purpose
To determine if left atrial (LA) appendage isolation (LAAI) in addition to PVI is a safe procedure and if it entails an improvement in the recurrence of AF.

Methods
Single-center retrospective study including patients with paroxysmic (PxAF) or persistent (PsAF) AF referred to cryoballoon ablation (CAB), comparing patients in whom LAAI was performed with those in whom only PVI was performed.

Results
131 patients (59.9 ± 12.3 years, 65.9% males) were referred to CAB in our center between 2017 and 2021. 103 patients (78.6%) had PxAF and 28 (21.4%) PsAF. Most patients had had AF for at least two years (65.6%), 12.2% between one and two years and 22.2% for less than one year. The median CHA2DS2-VASc score was 1 [0-2] and 72.5% had permanent anticoagulation indication. 90.1% had tried at least one antiarrhythmic drug (AAD) before the procedure (57.3% one AAD, the rest at least two AADs), being amiodarone (46.2%) and flecainide (46.2%) the most commonly used. Cardioversion prior to CAB was performed in 57.3% of patients.
The most common anatomy was 4 independent pulmonary veins (81.7%), followed by left common trunk (10.7%). LAAI was performed in 41 patients (31.3%) and it was performed more frequently in patients with PsAF and permanent anticoagulation indication, as well as in hypertense patients with bigger LA diameter (Table 1). The rate of complications was low in both groups, highlighting the absence of periprocedural cardioembolic stroke (CES) and the low rate of CES in the follow-up (2.1%) (median time to the apparition of the CES 27 [20-27] months), with no statically significative differences between LAAI and PVI groups.
During the 23 [13-37] months of follow-up, 32 patients (24.4%) had a recurrence after the 3-month blanking period (time to apparition of recurrence of 11 [6-21.75] months). There were no statically significant differences in the recurrences or in the complications between LAAI and PVI groups, neither in PxAF nor in PsAF patients (Table 2), although PxAF patients tended to have less recurrences when LAAI was performed (11.1% vs 25.0%, p=0.175).
On the other hand, the 1-year success rate (defined as the absence of recurrence in the 12 months following the blanking period), was 80.2% (out of 96 patients who had at least 15-month follow-up), with no statically significative differences between LAAI and PVI groups (80.8% vs 80%, p=0.933).

Conclusions
LAAI is a safe procedure with a low rate of complications and no evidence of increased risk of CES in the follow-up. Although LAAI did not entail a lower recurrence rate, it could have a role in selected PxAF patients. Larger studies with longer follow-up are needed to confirm our data.