Abstract 2645: Low Wall Motion Velocity of Left Atrial Appendage Predicts Thrombus Formation Caused by Atrial Appendage Dysfunction in Acute Stroke Patients with Atrial Fibrillation
It is well established that transesophageal echocardiography (TEE) is the most useful examination to detect thromboembolic sources in acute stroke patients, in spite of semi-invasive procedure. Transthoracic echocardiography (TTE) is less invasive, whereas it is sometimes difficult to detect thrombus in left atrial appendage (LAA). The aim of this study was to elucidate whether LAA wall motion measured by TTE was useful for detecting LAA thrombus. We performed TTE and TEE in 169 consecutive acute ischemic stroke patients with AF within 7 days after the onset (male, n=117, 71 ± 11 years old; female, n=52, 75 ± 10 years old). LAA wall motion velocity (LAWV) was measured by tissue Doppler imaging at LAA tip from parasternal short axis view of TTE. Patients were prospectively followed-up until primary endpoints such as stroke recurrence or death (mean follow-up period of 362 days). LAWV was significantly lower in patients with LAA thrombus than in those without thrombus (8.1 ± 1.9 vs. 11.6 ± 4.1 cm/s, P<0.01). LAWV was significantly correlated with LAA peak emptying flow velocity (R=0.74, P<0.01). The multivariate logistic regression analysis showed that low LAWV (<9.3 cm/s) was an independent predictor of LAA thrombus formation (odds ratio, 16.45; 95% confidence interval, 4.57–59.25; P<0.01). Stroke recurrence occurred in 24 patients (14%) during follow-up. The Cox multivariate proportional hazard analysis revealed that low LAWV (<9.3 cm/s) was an independent predictor for stroke recurrence (hazard ratio, 5.0; 95% confidence interval, 1.14 –21.74; P<0.05). Kaplan-Meier survival analysis showed that stroke recurrence rates were markedly higher in patients with low LAWV than in those with high LAWV (26% vs. 6%, P<0.01). In conclusion, LAWV successfully detected LAA dysfunction which caused LAA thrombus. Low LAWV may be a non-invasive predictor for stroke recurrence in ischemic stroke patients.