title: Three-dimensional analysis of the left atrial appendage for detecting paroxysmal atrial fibrillation in acute ischemic stroke.
abstract: BACKGROUND
  Atrial fibrillation impairs left atrial appendage function and the thrombus formation in the left atrial appendage is a major cause of cardioembolic stroke.
  
  
  OBJECTIVE
  To evaluate the association between the volume of the left atrial appendage measured by real-time three-dimensional transesophageal echocardiography and presence of paroxysmal atrial fibrillation in patients with cerebral infarction or transient ischemic attack.
  
  
  METHODS
  Real-time three-dimensional transesophageal echocardiography was performed to measure left atrial appendage end-diastolic and end-systolic volumes to calculate left atrial appendage ejection fraction. Patients with normal sinus rhythm at the time of real-time three-dimensional transesophageal echocardiography were divided into groups with and without paroxysmal atrial fibrillation. Volumetric data were corrected with the body surface area.
  
  
  RESULTS
  Of 146 patients registered, 102 (29 women, 72·2 ± 10·7 years) were normal sinus rhythm at the examination. In 23 patients with paroxysmal atrial fibrillation, left atrial appendage end-diastolic volume (4·78 ± 3·00 ml/m(2) vs. 3·14 ± 2·04 ml/m(2), P = 0·003) and end-systolic volume (3·10 ± 2·47 ml/m(2) vs. 1·39 ± 1·56 ml/m(2), P < 0·001) were larger and left atrial appendage ejection fraction (37·3 ± 19·1% vs. 57·1 ± 17·5%, P < 0·001) was lower than in the other 79 patients without paroxysmal atrial fibrillation. The optimal cutoff for left atrial appendage peak flow velocity to predict paroxysmal atrial fibrillation was 39·0 cm/s (sensitivity, 54·6%; specificity, 89·7%; c-statistic, 0·762). The cutoffs for left atrial appendage end-diastolic volume, end-systolic volume, and ejection fraction were 4·52 ml/m(2) (sensitivity, 47·8%; specificity, 82·3%; c-statistic, 0·694), 1·26 ml/m(2) (sensitivity, 91·3%; specificity, 60·3%; c-statistic, 0·806), and 47·9% (sensitivity, 78·3%; specificity, 74·7%; c-statistic, 0·774), respectively. In multivariate analysis, all these parameters were independently associated with paroxysmal atrial fibrillation after adjusting for sex, age, diabetes mellitus, and previous stroke.
  
  
  CONCLUSIONS
  Left atrial appendage volumetric analysis by real-time three-dimensional transesophageal echocardiography is a promising method for detecting paroxysmal atrial fibrillation in acute cerebral infarction or transient ischemic attack.
authors.affiliation: Department of Cerebrovascular Medicine, National Cerebral and Cardiovascular Center, Osaka, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Tanaka
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Koga
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Sato
authors.forename: Rieko
authors.initials: R
authors.lastname: Suzuki
authors.forename: Kazuo
authors.initials: K
authors.lastname: Minematsu
authors.forename: Kazunori
authors.initials: K
authors.lastname: Toyoda
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001281:Atrial Fibrillation / Q000175:diagnosis* / Q000209:etiology*; D016279:Atrial Function, Left; D002545:Brain Ischemia / Q000150:complications; D017548:Echocardiography, Transesophageal / Q000379:methods; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D012044:Regression Analysis; D020521:Stroke / Q000150:complications* / Q000209:etiology
keywords: atrial fibrillation; ejection fraction; ischemic stroke; left atrial appendage; real-time three-dimensional transesophageal echocardiography; volume measurement