title: A novel contribution towards coherent and reproducible intravalvular measurement of the aortic annulus by multidetector computed tomography ahead of transcatheter aortic valve implantation.
abstract: BACKGROUND
  As current multidetector computed tomography (MDCT) measurements underestimate the size of the aortic annulus ahead of transcatheter aortic valve implantation (TAVI), a strategy of approximate annulus area oversizing has been adopted recently.
  
  
  OBJECTIVE
  To measure the aortic annulus using a novel complementary intravalvular MDCT slice.
  
  
  METHODS
  Fifty-five patients with severe aortic stenosis were selected for MDCT ahead of and 1 month after CoreValve(®) TAVI. Two MDCT slices were analysed and compared: the current standard virtual basal ring (VBR) at the nadir of the aortic cusps; and a novel slice, defined as the basal (lowest) complete commissural coaptation (BCCC) plane.
  
  
  RESULTS
  BCCC is an intravalvular plane lying 5.2±0.8 mm above the VBR. The BCCC annulus is almost circular, unlike the VBR (mean eccentricity index 0.09±0.04 vs 0.3±0.1, respectively). The mean BCCC annulus diameter was 26.6±2.3 mm, 16% larger than that of the VBR (23.9±2.2 mm; P<0.001). The BCCC annulus area proved coherent with the orifice area measured after TAVI on the projection of the same slice (i.e. systematically equal to or greater than the latter [mean difference, +2.3±1.4 mm]), in contrast to the wider scatter found for the VBR (-1.3±2.0 mm). Once the sclerotic calcified valves have been pushed back by the implant, the aortic orifice after TAVI will inevitably be equal to or less than the diameter of the virtually unvalved annulus before TAVI.
  
  
  CONCLUSIONS
  Based on the present results, we recommend including a BCCC slice to complete aortic annulus sizing, in order to optimize implant calibration.
authors: Department of Cardiology and Interventional Cardiology, Hôpital Cardiologique Louis-Pradel, Université Claude-Bernard, Inserm UMR 1060, Lyon, France.
authors: Julie
authors: J
authors: Dementhon
authors: Department of Cardiology and Interventional Cardiology, Hôpital Cardiologique Louis-Pradel, Université Claude-Bernard, Inserm UMR 1060, Lyon, France.
authors: Gilles
authors: G
authors: Rioufol
authors: Department of Cardiovascular Surgery, Hôpital Cardiologique Louis-Pradel, Université Claude-Bernard, Inserm UMR 1060, Lyon, France.
authors: Jean-François
authors: JF
authors: Obadia
authors: Department of Cardiovascular Surgery, Hôpital Cardiologique Louis-Pradel, Université Claude-Bernard, Inserm UMR 1060, Lyon, France.
authors: Mathieu
authors: M
authors: Vergnat
authors: Department of Cardiology and Interventional Cardiology, Hôpital Cardiologique Louis-Pradel, Université Claude-Bernard, Inserm UMR 1060, Lyon, France.
authors: Lisa
authors: L
authors: Green
authors: Department of Radiology, Hôpital Cardiologique Louis-Pradel, Université Claude-Bernard, Lyon, France.
authors: Pierre
authors: P
authors: Croisille
authors: Department of Radiology, Hôpital de la Croix-Rousse, Université Claude-Bernard, Lyon, France.
authors: Loïc
authors: L
authors: Boussel
authors: Department of Biostatistics, UMR 5558, Hospices Civils de Lyon, Université Claude-Bernard, Lyon, France.
authors: Julien
authors: J
authors: Peron
authors: Department of Radiology, Hôpital Cardiologique Louis-Pradel, Université Claude-Bernard, Lyon, France.
authors: Didier
authors: D
authors: Revel
authors: Department of Cardiology and Interventional Cardiology, Hôpital Cardiologique Louis-Pradel, Université Claude-Bernard, Inserm UMR 1060, Lyon, France. Electronic address: gerard.finet@univ-lyon1.fr.
authors: Gérard
authors: G
authors: Finet
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000000981:diagnostic imaging* / Q000601:surgery; D001024:Aortic Valve Stenosis / Q000175:diagnosis / Q000601:surgery*; D017548:Echocardiography, Transesophageal / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D061330:Multidetector Computed Tomography / Q000379:methods*; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013997:Time Factors; D065467:Transcatheter Aortic Valve Replacement / Q000379:methods*; D055815:Young Adult
keywords: Aortic valve stenosis; Calibration; Medtronic CoreValve(®); Multidetector computed tomography; Remplacement valvulaire aortique percutané; Rétrécissement aortique; Sizing; Tomodensitométrie; Transcatheter aortic valve implantation