title: Assessment of left atrial appendage by live three-dimensional echocardiography: early experience and comparison with transesophageal echocardiography.
abstract: BACKGROUND
  Live Three-Dimensional Echocardiography (L3D, Sonos 7500, Philips) has the potential to visualize all cardiac structures including left atrial appendage (LAA). We tested the feasibility of evaluating LAA by L3D and compared the findings to transthoracic echocardiography (2D) and in a subset of patients with transesophageal echocardiography (TEE).
  
  
  METHODS
  L3D images were obtained in 204 consecutive patients referred for routine 2D or TEE. We performed wide-angled acquisitions from parasternal and apical views. TomTec system (4D Cardio-view, RT 1.2) was used to visualize LAA from multiple vantage points.
  
  
  RESULTS
  LAA was adequately visualized by L3D in 139 of 204 (68.1%) patients. L3D visualization was dependent on image quality, suboptimal in 100 and diagnostic in 104 patients. Overall, LAA was visualized in 93 (45.5%) patients by 2D compared to 139 (68.1%) by L3D (P < 0.0001). In 100 patients with suboptimal image quality by L3D, LAA visualization was 16% by 2D and 35% by L3D, whereas in 104 patients with diagnostic images, LAA was visualized in 77 (74%) by 2D and in all 104 (100%) patients by L3D (P < 0.0001). In 37 patients referred for transesophageal echocardiography (TEE), live three-dimensional echocardiography (L3D) visualized left atrial appendage (LAA) in 34 patients with diagnostic image quality. Eight patients with LAA thrombi on TEE had thrombi detected by L3D as well. All patients with LAA thrombus had enlarged LA by both 2D and TEE.
  
  
  CONCLUSIONS
  L3D is a promising technique in evaluation of LAA with and without thrombi. In patients with good quality transthoracic images L3D may be used as a screening tool in assessment of LAA.
authors.affiliation: Division of Cardiology, University of Texas Medical Branch, Galveston, Texas 77555-0766, USA.
authors.forename: Ildiko
authors.initials: I
authors.lastname: Agoston
authors.forename: Tianrong
authors.initials: T
authors.lastname: Xie
authors.forename: Frank L
authors.initials: FL
authors.lastname: Tiller
authors.forename: Atiar M
authors.initials: AM
authors.lastname: Rahman
authors.forename: Masood
authors.initials: M
authors.lastname: Ahmad
mesh_terms: D000328:Adult; D000368:Aged; D020517:Atrial Appendage / Q000000981:diagnostic imaging*; D016009:Chi-Square Distribution; D003328:Coronary Thrombosis / Q000000981:diagnostic imaging; D004452:Echocardiography; D019560:Echocardiography, Three-Dimensional; D017548:Echocardiography, Transesophageal; D005240:Feasibility Studies; D005260:Female; D006331:Heart Diseases / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged