title: Transcatheter aortic valve implantation: role of multi-detector row computed tomography to evaluate prosthesis positioning and deployment in relation to valve function.
abstract: OBJECTIVE
  Aortic regurgitation after transcatheter aortic valve implantation (TAVI) is one of the most frequent complications. However, the underlying mechanisms of this complication remain unclear. The present evaluation studied the anatomic and morphological features of the aortic valve annulus that may predict aortic regurgitation after TAVI.
  
  
  RESULTS
  In 53 patients with severe aortic stenosis undergoing TAVI, multi-detector row computed tomography (MDCT) assessment of the aortic valve apparatus was performed. For aortic valve annulus sizing, two orthogonal diameters were measured (coronal and sagittal). In addition, the extent of valve calcifications was quantified. At 1-month follow-up after procedure, MDCT was repeated to evaluate and correlate the prosthesis deployment to the presence of aortic regurgitation. Successful procedure was achieved in 48 (91%) patients. At baseline, MDCT demonstrated an ellipsoid shape of the aortic valve annulus with significantly larger coronal diameter when compared with sagittal diameter (25.1 +/- 2.4 vs. 22.9 +/- 2.0 mm, P < 0.001). At follow-up, MDCT showed a non-circular deployment of the prosthesis in six (14%) patients. Moderate post-procedural aortic regurgitation was observed in five (11%) patients. These patients showed significantly larger aortic valve annulus (27.3 +/- 1.6 vs. 24.8 +/- 2.4 mm, P = 0.007) and more calcified native valves (4174 +/- 1604 vs. 2444 +/- 1237 HU, P = 0.005) at baseline and less favourable deployment of the prosthesis after TAVI.
  
  
  CONCLUSIONS
  Multi-detector row computed tomography enables an accurate sizing of the aortic valve annulus and constitutes a valuable imaging tool to evaluate prosthesis location and deployment after TAVI. In addition, MDCT helps to understand the underlying mechanisms of post-procedural aortic regurgitation.
authors.affiliation: Department of Cardiology and Cardiothoracic Surgery, Leiden University Medical Center, Albinusdreef 2, Leiden 2333 ZA, The Netherlands.
authors.forename: Victoria
authors.initials: V
authors.lastname: Delgado
authors.forename: Arnold C T
authors.initials: AC
authors.lastname: Ng
authors.forename: Nico R
authors.initials: NR
authors.lastname: van de Veire
authors.forename: Frank
authors.initials: F
authors.lastname: van der Kley
authors.forename: Joanne D
authors.initials: JD
authors.lastname: Schuijf
authors.forename: Laurens F
authors.initials: LF
authors.lastname: Tops
authors.forename: Arend
authors.initials: A
authors.lastname: de Weger
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Tavilla
authors.forename: Albert
authors.initials: A
authors.lastname: de Roos
authors.forename: Lucia J
authors.initials: LJ
authors.lastname: Kroft
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Schalij
authors.forename: Jeroen J
authors.initials: JJ
authors.lastname: Bax
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000800:Angioplasty, Balloon / Q000379:methods; D001021:Aortic Valve / Q000473:pathology*; D001022:Aortic Valve Insufficiency / Q000000981:diagnostic imaging* / Q000209:etiology / Q000473:pathology; D001024:Aortic Valve Stenosis / Q000601:surgery*; D004452:Echocardiography; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects* / Q000379:methods; D006801:Humans; D008297:Male; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000209:etiology; D014057:Tomography, X-Ray Computed / Q000379:methods*