Background
Atrial fibrillation (AF) remains the most common cardiac arrhythmia, with pulmonary vein isolation (PVI) established as the cornerstone of interventional treatment.
However, in patients with persistent AF (PersAF), the success rates of PVI alone tend to be limited, One promising additional target that has garnered increasing attention is the left atrial appendage (LAA). In recent years, cryoballoon (CB) technology has become a prominent tool for achieving durable PVI due to its safety and efficacy profile. Its application for LAAI has been investigated as a potentially advantageous alternative to radiofrequency ablation and positive effect on long-term outcome has been reported. However, the available data is limited, varies across a wide range and lacks long-term assessments. This study sought to investigate the clinical impact on CB-based LAAI in addition to PVI, the incidence of post-procedural LAA thrombus formation and thromboembolism as well as the impact of interventional LAA-closure.
Methods:
This is a prospective, interventional, single centre study. Consecutive patients with symptomatic PersAF were prospectively enrolled. In total 23 patients with PersAF underwent PVI plus LAAI using the Arctic front advance (CB2) or Arctic front advance pro (CB4) CB system. Percutaneous LAA-closure was performed within 2-3 months in all patients by implanting an endocardial LAA-closure device. Prior to LAA-closure, LAAI-durability was systematically assessed by invasive remapping studies utilizing a circular mapping catheter.
Results:
The median age was 70 (60.5, 70.0) years. A total of 100% of PVs were successfully isolated using the CB only (n=91/91). Concerning LAAI, a total of 21/23 (91%) remained isolated at the end of the procedure. After the ablation procedure including LAAI all patients were scheduled for TEE assessment and LAA closure. TEE was performed after a mean of 54 ± 19 days. In 6/23 (26%) patients LAA thrombus formation was detected after LAAI. A total of 23/23 patients (100%) received LAAC after a mean of 72 ± 45 days. Durability of LAAI was assessed utilizing a spiral mapping catheter in 23/23 patients (100%). In a total of 17/23 (74%) patients durable LAA isolation was detected. Durable PVI of all PVs was detected in 16/23 (70%) patients.
During a mean follow-up of 13 ± 3.4 months, stable sinus rhythm was maintained in 15 (65%) patients. The LAA showed reconnection in 3/23 (13%) patients with arrhythmia recurrence. In patients with LAA-thrombus after LAAI 6/6 (100%) showed durable LAAI. In patients without durable LAAI the rate of thrombus was 0/6 (0%) (p<0.001). During follow-up one stroke (318 days after LAAC) and one device thrombus (56 days after LAAC) occurred. Both patients had durable LAAI and continued OAC, despite LAAC.
Conclusion:
While CB-based LAAI may offer benefits in managing persistent AF, it presents a significant risk of thrombus formation in the LAA, even with appropriate OAC. Early closure of the LAA following LAAI appears promising in mitigating these risks, but further evidence is needed to establish clear best practices.
