title: Prediction of optimal deployment projection for transcatheter aortic valve replacement: angiographic 3-dimensional reconstruction of the aortic root versus multidetector computed tomography.
abstract: BACKGROUND
  Identifying the optimal fluoroscopic projection of the aortic valve is important for successful transcatheter aortic valve replacement (TAVR). Various imaging modalities, including multidetector computed tomography (MDCT), have been proposed for prediction of the optimal deployment projection. We evaluated a method that provides 3-dimensional angiographic reconstructions (3DA) of the aortic root for prediction of the optimal deployment angle and compared it with MDCT.
  
  
  RESULTS
  Forty patients undergoing transfemoral TAVR at St Paul's Hospital, Vancouver, Canada, were evaluated. All underwent preimplant 3DA and 68% underwent preimplant MDCT. Three-dimensional angiographic reconstructions were generated from images of a C-arm rotational aortic root angiogram during breath-hold, rapid ventricular pacing, and injection of 32 mL contrast medium at 8 mL/s. Two independent operators prospectively predicted perpendicular valve projections. The implant angle was chosen at the discretion of the physician performing TAVR. The angles from 3DA, from MDCT, the implant angle, and the postdeployment perpendicular prosthesis view were compared. The shortest distance from the postdeployment perpendicular prosthesis projection to the regression line of predicted perpendicular projections was calculated. All but 1 patient had adequate image quality for reproducible angle predictions. There was a significant correlation between 3DA and MDCT for prediction of perpendicular valve projections (r=0.682, P<0.001). Deviation from the regression line of predicted angles to the postdeployment prosthesis view was 5.1±4.6° for 3DA and 7.9±4.9° for MDCT (P=0.01).
  
  
  CONCLUSIONS
  Three-dimensional angiographic reconstructions and MDCT are safe, practical, and accurate imaging modalities for identifying the optimal perpendicular valve deployment projection during TAVR.
authors.affiliation: St Paul's Hospital, University of British Columbia, Vancouver, British Columbia, Canada.
authors.forename: Ronald K
authors.initials: RK
authors.lastname: Binder
authors.forename: Jonathon
authors.initials: J
authors.lastname: Leipsic
authors.forename: David
authors.initials: D
authors.lastname: Wood
authors.forename: Teri
authors.initials: T
authors.lastname: Moore
authors.forename: Stefan
authors.initials: S
authors.lastname: Toggweiler
authors.forename: Alex
authors.initials: A
authors.lastname: Willson
authors.forename: Ronen
authors.initials: R
authors.lastname: Gurvitch
authors.forename: Melanie
authors.initials: M
authors.lastname: Freeman
authors.forename: John G
authors.initials: JG
authors.lastname: Webb
mesh_terms: D001021:Aortic Valve / Q000000981:diagnostic imaging* / Q000473:pathology; D001024:Aortic Valve Stenosis / Q000175:diagnosis* / Q000601:surgery; D006328:Cardiac Catheterization; D017023:Coronary Angiography / Q000379:methods; D005240:Feasibility Studies; D005471:Fluoroscopy; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D021621:Imaging, Three-Dimensional; D061330:Multidetector Computed Tomography; D011379:Prognosis; D011446:Prospective Studies