Management strategies to prevent stroke in patients with atrial fibrillation and malignant left atrial appendage.

Background: Patients with atrial fibrillation and malignant left atrial appendage (LAA) may benefit from LAA closure (LAAC); however, evidence is limited.

Objective: The purpose of this study was to determine management strategies and clinical outcomes in patients with atrial fibrillation and malignant LAA.

Methods: Malignant LAA was defined as ischemic stroke or LAA thrombus formation despite continuous oral anticoagulation (OAC) therapy (continuous for ≥3 weeks). We studied 80 patients with malignant LAA treated with LAAC. We compared these patients first against 44 patients with malignant LAA treated with OAC alone and second against 114 patients without malignant LAA who were treated with LAAC for conventional indications.

Results: Among patients with malignant LAA (first comparison), those treated with LAAC had a higher 1-year cumulative incidence of ischemic stroke than did patients treated with OAC alone (6.3% vs 5.3%; log-rank, P = .09) whereas the difference in stroke risk while receiving OAC was comparable (2.7% vs 5.3%; log-rank, P = .84). Furthermore, all disabling stroke events in patients with malignant LAA treated with LAAC occurred only while not receiving OAC. Among patients treated with LAAC (second comparison), those with malignant LAA had a higher 1-year cumulative incidence of ischemic stroke (and ischemic stroke due to device-related thrombosis) than did those without malignant LAA (6.3% vs 2.2%; log-rank, P = .009 and 2.2% vs 0%; log-rank, P = .04, respectively). However, these differences in stroke risk were no longer significant while receiving OAC (2.7% vs 1.0%; log-rank, P = .11).

Conclusion: Both performing LAAC and continuation of OAC may be options to prevent ischemic stroke in patients with high thromboembolic risk and malignant LAA.