title: Optimal fluoroscopic viewing angles of left-sided heart structures in patients with aortic stenosis and mitral regurgitation based on multislice computed tomography.
abstract: BACKGROUND
  Transcatheter interventions are currently undertaken using "generic" fluoroscopic viewing angles. However, the position and orientation of heart structures may vary across patients and disease-specific remodeling processes.
  
  
  OBJECTIVE
  This study uses multislice computed tomography to determine optimal fluoroscopic viewing angles of the aortic and mitral annuli, the left atrial appendage and the atrial septum. We explored differences between patients with severe aortic stenosis (AS) and severe mitral regurgitation (MR).
  
  
  RESULTS
  The multislice computed tomographies of 28 patients with severe aortic stenosis (AS) and 32 patients with severe functional mitral regurgitation (MR) were analyzed. For each patient, we evaluated the optimal fluoroscopic viewing angles of the aortic and mitral annuli (en face, maximal and minimal diameters, aortic root with right, left and non coronary sinus in center), left atrial appendage orifice (en face, maximal and minimal diameters), and atrial septum (fossa ovalis) en face. The TAVR implantation view with right coronary sinus in center was LAO 9 - CRA 0 in the AS group and LAO 6 - CAU 5 in the MR group (p = NS). AS and MR patients differed significantly with respect to the fluoroscopic angulation of the aortic annulus en face (8.3°), the aortic annulus maximal (17.7°) and minimal (18.5°) diameters, the mitral annulus aorto-mural diameter (11.3°), and the left atrial appendage orifice en face (11.1°) (all p-values<0.05).
  
  
  CONCLUSIONS
  Optimal fluoroscopic viewing angles of left-sided structures vary considerably between patients. Multislice computed tomography is a valuable tool to determine the most procedurally relevant angulations, with the potential to optimize procedural safety, efficacy and duration.
authors.affiliation: Department of Medicine, Division of Cardiology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Marco
authors.initials: M
authors.lastname: Spaziano
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.affiliation: Department of Medicine, Division of Cardiology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Meti
authors.affiliation: Department of Medicine, Division of Cardiology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Vaquerizo
authors.affiliation: St. Paul's Hospital, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Philipp
authors.initials: P
authors.lastname: Blanke
authors.affiliation: Department of Medicine, Division of Cardiology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Jine
authors.initials: J
authors.lastname: Deli-Hussein
authors.affiliation: Department of Medicine, Division of Cardiology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Chetrit
authors.affiliation: Department of Medicine, Division of Cardiology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Christos
authors.initials: C
authors.lastname: Galatos
authors.affiliation: Department of Medicine, Division of Cardiology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Jean
authors.initials: J
authors.lastname: Buithieu
authors.affiliation: Department of Cardiovascular Surgery, German Heart Centre Munich, Munich, Germany.
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Lange
authors.affiliation: Department of Medicine, Division of Cardiology, McGill University Health Centre, Montreal, Quebec, Canada.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Martucci
authors.affiliation: St. Paul's Hospital, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Jonathon
authors.initials: J
authors.lastname: Leipsic
authors.affiliation: Department of Medicine, Division of Cardiology, McGill University Health Centre, Montreal, Quebec, Canada; Department of Cardiovascular Surgery, German Heart Centre Munich, Munich, Germany. Electronic address: nicolopiazza@mac.com.
authors.forename: Nicolo
authors.initials: N
authors.lastname: Piazza
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D059925:Anatomic Landmarks; D001021:Aortic Valve / Q000000981:diagnostic imaging*; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging* / Q000628:therapy; D020517:Atrial Appendage / Q000000981:diagnostic imaging*; D054087:Atrial Septum / Q000000981:diagnostic imaging*; D006328:Cardiac Catheterization; D003937:Diagnosis, Differential; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000000981:diagnostic imaging*; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging* / Q000628:therapy; D061330:Multidetector Computed Tomography; D015588:Observer Variation; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012720:Severity of Illness Index
keywords: Fluoroscopic anatomy; Interventional imaging; Multi-slice computed tomography; Multiplanar reconstruction; Transcatheter cardiac intervention