title: Quantitative multi-slice computed tomography assessment of the mitral valvular complex for transcatheter mitral valve interventions part 1: systematic measurement methodology and inter-observer variability.
abstract: OBJECTIVE
  Transcatheter mitral valve replacement (TMVR) is an emerging technology with the potential to treat patients with severe mitral regurgitation at excessive risk for surgical mitral valve surgery. Multimodality imaging of the mitral valvular complex and surrounding structures will be an important component for patient selection for TMVR. Our aim was to describe and evaluate a systematic multi-slice computed tomography (MSCT) image analysis methodology that provides measurements relevant for transcatheter mitral valve replacement.
  
  
  RESULTS
  A systematic step-by-step measurement methodology is described for structures of the mitral valvular complex including: the mitral valve annulus, left ventricle, left atrium, papillary muscles and left ventricular outflow tract. To evaluate reproducibility, two observers applied this methodology to a retrospective series of 49 cardiac MSCT scans in patients with heart failure and significant mitral regurgitation. For each of 25 geometrical metrics, we evaluated inter-observer difference and intra-class correlation. The inter-observer difference was below 10% and the intra-class correlation was above 0.81 for measurements of critical importance in the sizing of TMVR devices: the mitral valve annulus diameters, area, perimeter, the inter-trigone distance, and the aorto-mitral angle.
  
  
  CONCLUSIONS
  MSCT can provide measurements that are important for patient selection and sizing of TMVR devices. These measurements have excellent inter-observer reproducibility in patients with functional mitral regurgitation.
authors.affiliation: Department of Medicine, Division of Cardiology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Pascal
authors.initials: P
authors.lastname: Thériault-Lauzier
authors.forename: Darren
authors.initials: D
authors.lastname: Mylotte
authors.forename: Magdalena
authors.initials: M
authors.lastname: Dorfmeister
authors.forename: Marco
authors.initials: M
authors.lastname: Spaziano
authors.forename: Ali
authors.initials: A
authors.lastname: Andalib
authors.forename: Samuel
authors.initials: S
authors.lastname: Mamane
authors.forename: Michael
authors.initials: M
authors.lastname: Chetrit
authors.forename: Philipp
authors.initials: P
authors.lastname: Blanke
authors.forename: Renzo
authors.initials: R
authors.lastname: Cecere
authors.forename: Jean
authors.initials: J
authors.lastname: Buithieu
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Martucci
authors.forename: Didier
authors.initials: D
authors.lastname: Tchetche
authors.forename: Thomas
authors.initials: T
authors.lastname: Modine
authors.forename: Nicolas
authors.initials: N
authors.lastname: van Mieghem
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Lange
authors.forename: Stephan
authors.initials: S
authors.lastname: Windecker
authors.forename: Luc
authors.initials: L
authors.lastname: Bilodeau
authors.forename: Jonathon
authors.initials: J
authors.lastname: Leipsic
authors.forename: Nicolo
authors.initials: N
authors.lastname: Piazza
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D006328:Cardiac Catheterization / Q000379:methods; D005260:Female; D006325:Heart Atria / Q000000981:diagnostic imaging*; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000379:methods; D006352:Heart Ventricles / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000000981:diagnostic imaging* / Q000601:surgery; D061330:Multidetector Computed Tomography; D015588:Observer Variation; D010210:Papillary Muscles / Q000000981:diagnostic imaging*; D018579:Patient Selection; D011474:Prosthesis Design; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018487:Ventricular Dysfunction, Left