Long-term outcomes after surgical ablation for atrial fibrillation in patients with continuous heart rhythm monitoring devices

Objectives: Surgical ablation for atrial fibrillation (AF) is an established therapy for the treatment of concomitant AF in cardiac surgery patients. We aim to present our prospective experience with 99 continuously monitored patients and investigate whether enhanced monitoring can identify patterns and factors influencing AF recurrence after surgical AF ablation. Methods: Ninety-nine patients (73 males; age: 68.0 ± 9.2 years) with documented preoperative AF (paroxysmal: 29; persistent: 18; longlasting persistent: 52, mean preoperative duration: 46 ± 53 months) underwent concomitant biatrial surgical ablation (Cox Maze III: 29), full set left atrial cryoablation (n = 22), high-intensity focused ultrasound (HIFU) box lesion (n = 46) or right-sided ablation (n = 2). Postoperative rhythm disclosure was provided via an implantable device. Scheduled follow-up was performed quarterly (mean ± standard deviation: 1.75 ± 1.16 years, 173.7 patient-years). Results: The mean postoperative AF burden during the follow-up was 7 ± 19% (median: 0.2%). Seventy-one and 82 patients had AF burden <1% and <5%, respectively. The preoperative AF duration, preoperative ejection fraction, mitral valve surgery and HIFU in patients with more persistent AF were associated with statistically significant higher postoperative AF burdens. The pattern of AF recurrence during the 3-month blanking period was associated with the amount of later AF recurrence. Conclusions: Continuous rhythm disclosure reveals that very small amounts of AF burden after surgical ablation are common. The preoperative duration of AF and the use of a box lesion only in patients with longer AF persistence history were independently associated with higher postoperative AF burden recurrence. The temporal AF pattern during the blanking period after ablation should be considered for further patient management and might serve as a prognostic factor.