Anatomical and electrical remodeling with incomplete left atrial appendage ligation: Results from the LAALA‐AF registry
We read with interest the article by Turagam et al. recently published in your journal discussing the outcomes of left atrial appendage (LAA) ligation with the transcatheter endo‐epicardial Lariat system followed by catheter ablation in 119 symptomatic patients with atrial fibrillation (AF) who were intolerant to oral anticoagulation (OAC).1 Their results suggest high procedural success defined as a reduction in LAA size and volume, LAA electrical activity, freedom of transient ischemic attack, and stroke at 1 year. The authors also reported a 10.8% peri‐procedural complication rate with the ligation procedure, and 27% recurrence of atrial arrhythmias at 1 year.1
We would like to raise some concerns regarding these results. First, the study was small and descriptive with no control group, which limits the capacity to draw conclusions about the safety and efficacy of the proposed approach. Second, although recruited patients had high CHADS2VASC and HAS‐BLED scores, and were labeled intolerant to OAC, the authors do not describe the reasons for intolerance. Moreover, 59% of patients were on warfarin preoperatively, while new oral anticoagulants (NOACs) are known to benefit this high‐risk group.2 NOACs are associated with less major intracranial hemorrhage and stroke, and potentially less major bleeding when compared with warfarin. Third, the authors refer to their follow‐up as long term. AF is a life‐long disease and recurrences after ablation continue well beyond 1 year.3 We would argue that this study is a short‐term analysis in relation to the lifelong risk, making the long‐term safety of stopping anticoagulation questionable.
The efficacy and safety of LAA exclusion, and whether OAC is required afterward are still unknown. In the upcoming years, the large ongoing Left Atrial Appendage Occlusion Study III (LAAOS III) will provide definitive answers. LAAOS III is a multicenter randomized controlled trial of surgical LAA exclusion. So far, we successfully randomized more than 3,700 patients undergoing cardiac surgery with a history of AF. We anticipate reaching our target of 4,700 patients in 2018.