title: Comparative assessment of left atrial appendage by transesophageal and combined two- and three-dimensional transthoracic echocardiography.
abstract: OBJECTIVE
  Our objective was to compare the utility of combined two-dimensional (2D) transthoracic echocardiography (TTE) and three-dimensional (3D) TTE versus 2D transesophageal echocardiography (TEE) in evaluation of the left atrium (LA) and LA appendage (LAA) for clot.
  
  
  BACKGROUND
  2DTEE, usually performed to visualize the LAA, is semi-invasive and not without risks. With improved technology the LAA has been increasingly visualized by 2DTTE and 3DTTE in many patients.
  
  
  METHODS
  We compared combined 2DTTE and 3DTTE with 2DTEE in evaluating the LA/LAA for a thrombus. Ninety-two patients underwent 2DTTE, 3DTTE, and 2DTEE. An additional 20 patients, in whom TEE could not be performed, underwent 2DTTE and 3DTTE.
  
  
  RESULTS
  LA and LAA could be visualized in all patients. Of 92 patients studied, 74 had no thrombus and 7 had thrombus in the LAA by all modalities. Eleven patients, 9 with atrial fibrillation (AF), had a suspected thrombus by 2DTEE, but 3DTTE cropping clearly showed these to be prominent pectinate muscles which were seen in short axis on 2DTEE as rounded echo dense masses and therefore mimicked thrombi. These 9 patients with AF underwent successful cardioversion without any complications. Of the 20 patients in whom TEE could not be performed, 19 had no thrombus in the LA/LAA and 1 had a clot in the LAA. These 19 patients underwent successful cardioversion without complications.
  
  
  CONCLUSIONS
  Our preliminary study suggests that combined 2DTTE and 3DTTE has comparable accuracy to TEE in evaluating the LA and LAA for thrombus. In some patients TEE, but not 3DTTE, may misdiagnose pectinate musculature as thrombus.
authors.affiliation: Division of Cardiovascular Diseases, University of Alabama at Birmingham, Birmingham, Alabama 35249, USA.
authors.forename: Gultekin
authors.initials: G
authors.lastname: Karakus
authors.forename: Visali
authors.initials: V
authors.lastname: Kodali
authors.forename: Vatsal
authors.initials: V
authors.lastname: Inamdar
authors.forename: Navin C
authors.initials: NC
authors.lastname: Nanda
authors.forename: Thouantosaporn
authors.initials: T
authors.lastname: Suwanjutah
authors.forename: Koteswara R
authors.initials: KR
authors.lastname: Pothineni
mesh_terms: D000328:Adult; D000368:Aged; D020517:Atrial Appendage / Q000000981:diagnostic imaging*; D004452:Echocardiography / Q000379:methods*; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011665:Pulmonary Valve Insufficiency / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult