title: Low wall velocity of left atrial appendage measured by trans-thoracic echocardiography predicts thrombus formation caused by atrial appendage dysfunction.
abstract: BACKGROUND
  Atrial fibrillation is associated with ischemic stroke because of thrombi that form within the left atrial appendage (LAA). The aim of this study was to develop a new parameter for LAA function that is easily performed using transthoracic echocardiography (TTE).
  
  
  METHODS
  TTE and transesophageal echocardiography were performed in 106 patients with stroke. LAA wall motion velocity (TTE-LAWV) was measured using Doppler tissue imaging at the LAA tip.
  
  
  RESULTS
  TTE-LAWV was significantly lower in patients with atrial fibrillation and LAA thrombus than in those with atrial fibrillation and no LAA thrombus and in sinus rhythm (7.5 +/- 1.9 vs 10.0 +/- 3.4 and 13.8 +/- 5.7 cm/s, respectively, P < .05). TTE-LAWV was significantly correlated with LAA emptying flow velocity (R = 0.462, P < .05). The multivariate logistic regression analysis showed that TTE-LAWV < 8.7 cm/s was an independent predictor of LAA thrombus formation (odds ratio, 9.473; 95% confidence interval, 1.172-76.55; P < .05).
  
  
  CONCLUSIONS
  TTE-LAWV can noninvasively evaluate LAA dysfunction and assist in the detection of LAA thrombus.
authors.affiliation: Department of Cardiology, Pulmonology, and Nephrology, Yamagata University School of Medicine, Yamagata, Japan.
authors.forename: Harutoshi
authors.initials: H
authors.lastname: Tamura
authors.forename: Tetsu
authors.initials: T
authors.lastname: Watanabe
authors.forename: Osamu
authors.initials: O
authors.lastname: Hirono
authors.forename: Satoshi
authors.initials: S
authors.lastname: Nishiyama
authors.forename: Shintaro
authors.initials: S
authors.lastname: Sasaki
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Shishido
authors.forename: Takehiko
authors.initials: T
authors.lastname: Miyashita
authors.forename: Takuya
authors.initials: T
authors.lastname: Miyamoto
authors.forename: Joji
authors.initials: J
authors.lastname: Nitobe
authors.forename: Takamasa
authors.initials: T
authors.lastname: Kayama
authors.forename: Isao
authors.initials: I
authors.lastname: Kubota
mesh_terms: D000368:Aged; D020517:Atrial Appendage / Q000000981:diagnostic imaging*; D001281:Atrial Fibrillation / Q000000981:diagnostic imaging* / Q000209:etiology*; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013927:Thrombosis / Q000150:complications* / Q000000981:diagnostic imaging*