Abstract WMP66: Left Atrial Appendage Flow Velocity is Associated With Ischemic Events and Brain Infarcts in Atrial Fibrillation

Abstract

Objective: Clinical predictors of ischemic stroke in the setting of atrial fibrillation (AF) have been identified, but there is limited data on predictors in the context of abnormal flow originating from the left atrial appendage. We hypothesize that reduced LAA flow velocity is associated with cerebrovascular ischemic events in patients with AF. Methods: We investigated consecutive patients with AF evaluated for ablation. Peak flow velocities at the orifice of the left atrial appendage (LAA) were obtained by transeosphageal echocardiography (TEE) studies, and elevated velocities were defined as greater than 40 cm/sec, in line with prior studies. The primary outcome was defined as the presence of any of the following: history of stroke/transient ischemic event, or non-lacunar brain infarct on brain imaging performed before the TEE. Univariate and multivariable analyses were performed to determine the association between LAA peak flow and the primary outcome, adjusting for CHADS2Vasc score. Results: We identified 322 patients with TEE performed. The mean age was 62.1 years and 24.5% men. Patients with LAA-flow velocity < 40 cm/sec were more likely to have the primary outcome (10.7% vs 4.3%, p=0.023). This association persisted after adjusting for CHADS2VASc (OR, 2.62; 95% CI, 1.09-6.33, p = 0.032). Conclusion: Low velocity in the LAA is associated with cerebrovascular ischemic events in patients with AF. More studies are needed to deterine whether LAA flow velocity can help risk stratify “low risk” patients with AF.