Low flow in the left atrial appendage assessed by transesophageal echocardiography is associated with increased stroke severity—Results of a single-center cross-sectional study

Abstract

Background: About 25% of strokes are thought to be cryptogenic. There is growing evidence that most of these cryptogenic strokes are thromboembolic and caused by an undetected atrial fibrillation. Measured slow flow in the left atrial appendage has been proposed to be an indicator for the thromboembolic risk since it is possibly associated with undetected atrial fibrillation. Methods: We evaluated all patients (n ¼ 909; mean of 62 years, 39% female) admitted with an ischemic stroke (84%) or transient ischemic attack to our university medical center who underwent transesophageal echocardiography examination 2012-2014. Baseline characteristics, cardio-/neurovascular risk factors, electrocardiogram monitoring data, National Institute of Health Stroke Scale values, the localization of the stroke, as well as transesophageal echocardiography findings were analyzed. Results: Stroke severity measured by the National Institute of Health Stroke Scale in patients with a low flow in the left atrial appendage was significantly higher than in patients without left atrial appendage low flow (p < 0.001). There was a threshold phenomenon in flow velocity at about 60 cm/s above which no significant change in National Institute of Health Stroke Scale values could be observed. These patients were significantly different concerning incidence of heart failure (10.6% vs. 2.3%; p < 0.001) and atrial fibrillation (32.2% vs. 8.8%; p < 0.001). However, threshold phenomenon of left atrial appendage flow was unchanged when excluding atrial fibrillation and heart failure patients. Conclusions: A low flow in the left atrial appendage was associated with clinically elevated stroke severity and could be indicated as an independent stroke risk factor. Further prospective studies are warranted to evaluate beneficial effects of therapeutic options in these patients also in the assumed absence of atrial fibrillation.

Machine Learning Model-Based Simple Clinical Information to Predict Decreased Left Atrial Appendage Flow Velocity

“…The left atrial appendage was proved to be a major source of emboli responsible for cardioembolic stroke in previous studies [ 24 ], and decreased LAAV has been proved to be a well-recognized risk factor for left atrial appendage thrombosis and stroke [ 6 , 24 , 25 , 26 ]. In clinical practice, TEE was regarded as the first technique of choice to measure the function of left atrial appendage, but TEE may cause severe discomfort in patients and, moreover, serious complications (such as esophageal damage) [ 27 ].…”

Stroke risk evaluation for patients with atrial fibrillation: Insights from left atrial appendage

“…Even patients with low CHA 2 DS 2 -VASc score may suffer a stroke. The score also fails to take into consideration the structure ( 31 , 115 ) and the hemodynamic characteristics for the LAA ( 37 , 116 , 117 ) in addition to other clinical markers ( 118 – 120 ). Thus, additional LAA features and clinical markers may further risk stratify stroke prevention for patients with AF.…”

Atrial Cardiopathy and Cryptogenic Stroke

“…Among 721 patients who underwent transesophageal echocardiography in a post hoc analysis of the Stroke Prevention in Atrial Fibrillation-III trial, reduced LAA flow velocity (<20 cm/s) was associated with thrombus formation and subsequent cardioembolic stroke (33). Similarly, a cross-sectional study of 909 stroke patients with or without AF found that decreased LAA flow velocity (<60 cm/s) was associated with clinically elevated stroke severity (34), and an observational study of 786 patients with cryptogenic stroke found that decreased LAA flow velocity on transesophageal echocardiography was associated with multiple infarcts (35). These results indicate that decreased flow velocity in the LAA is an additional risk factor for cardioembolic stroke, regardless of whether AF exists.…”