title: Comparing Measurements of CT Angiography, TEE, and Fluoroscopy of the Left Atrial Appendage for Percutaneous Closure.
abstract: BACKGROUND
  Left atrial appendage (LAA) closure requires accurate preprocedural measurements, and trans-esophageal echocardiography (TEE), cardiac computed tomography angiography (CCTA) and fluoroscopy can be utilized. However, correlations between these measurements remain inadequately assessed.
  
  
  METHODS
  Patients who underwent LAA closure at Vancouver General Hospital who had baseline LAA measurements by CCTA, TEE, and fluoroscopy were included in this analysis. CCTAs were performed with prospective-ECG-gating with Toshiba 320-detector or Siemens second generation 128-slice dual-source scanners, and images interpreted with VitreaWorkstation.™ LAA maximal dimensions were obtained for all patients at: (1) Amplatzer Cardiac Plug (ACP)/Amulet landing zone 10 mm within orifice, (2) WATCHMAN ostium, and (3) WATCHMAN depth measurements. Correlations and agreements were compared.
  
  
  RESULTS
  We report 50 consecutive patients who underwent LAA closure (8 ACP, 10 Amulet, 32 WATCHMAN). Average age was 75.2 ± 8.7 years, mean CHADS2 score 3.0 ± 1.3, and CHA2 DS2 -VASc 4.7 ± 1.5. Procedural device implantation success was 100%. For ACP landing zone, mean maximal measurements were 24.1 ± 4.7 mm with CCTA, 22.3 ± 4.9 mm TEE, and 19.9 ± 5.6 mm fluoroscopy (P < 0.001); R value 0.81 fluoroscopy/CTA, 0.67 fluoroscopy/TEE, and 0.80 CTA/TEE. For WATCHMAN ostium, mean maximal measurements were 25.8 ± 4.7 mm CCTA (P < 0.001 vs. fluoroscopy, P = 0.16 vs. TEE), 25.1 ± 4.4 mm TEE (P = 0.016 vs. fluoroscopy), and 23.8 ± 4.9 mm fluoroscopy; R value 0.71 fluoroscopy/CTA, 0.65 fluoroscopy/TEE, and 0.74 CTA/TEE. Depth measurements were 34.3 ± 5.7 mm with CCTA, 31.1 ± 6.5 mm TEE, and 27.8 ± 7.1 mm fluoroscopy (all P < 0.01); and correlations with R value 0.28 fluoroscopy/CTA, 0.22 fluoroscopy/TEE, and 0.56 CTA/TEE.
  
  
  CONCLUSIONS
  All 3 imaging modalities correlated with ACP landing zone and WATCHMAN ostium measurements, with CCTA providing the largest measurements, followed by TEE and fluoroscopy.
authors.affiliation: Division of Cardiology, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Saw
authors.affiliation: Division of Cardiology, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Peter
authors.initials: P
authors.lastname: Fahmy
authors.affiliation: Division of Cardiology, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Ryan
authors.initials: R
authors.lastname: Spencer
authors.affiliation: Division of Cardiology, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Roshan
authors.initials: R
authors.lastname: Prakash
authors.affiliation: Division of Radiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Patrick
authors.initials: P
authors.lastname: McLaughlin
authors.affiliation: Division of Radiology, Vancouver General Hospital, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Savvas
authors.initials: S
authors.lastname: Nicolaou
authors.affiliation: Division of Cardiology, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Tsang
mesh_terms: D000368:Aged; D020517:Atrial Appendage / Q000000981:diagnostic imaging* / Q000601:surgery*; D006348:Cardiac Surgical Procedures / Q000295:instrumentation / Q000379:methods*; D000072226:Computed Tomography Angiography / Q000379:methods*; D017548:Echocardiography, Transesophageal / Q000379:methods*; D005260:Female; D005471:Fluoroscopy / Q000379:methods*; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D055989:Septal Occluder Device; D025321:Surgery, Computer-Assisted / Q000379:methods
keywords: CT angiography; TEE; WATCHMAN; amulet; atrial fibrillation; left atrial appendage (LAA) closure; stroke