title: Relationship of mitral valve annulus plane and circumflex-right coronary artery plane: Implications for Transcatheter Mitral Valve Implantation.
abstract: OBJECTIVE
  Transcatheter mitral valve implantation (TMVI) is a novel technology for patients with severe mitral valve disease but at high surgical risk. Imaging guidance during the procedure is critical for successful device deployment. Identification of the mitral annular plane (MAP) with fluoroscopy during the procedure is limited by lack of clearly defined landmarks. We hypothesized that a plane defined by left circumflex-right coronary arteries (LCX-RCA) would have a consistent relationship to MAP.
  
  
  RESULTS
  We studied 25 patients with gated cardiac computed tomography. We identified the MAP and the LCX-RCA plane in mid systole and diastole. The distance between the two planes in prespecified four points (anterior, posterior, medial, and lateral) in the apical 2 and 3-chamber views. Alignment of the planes was described by cranial/caudal angulation for both planes in RAO 30° and LAO 90° (lateral) angulation. Mean age was 81 ± 9 years, 56% of patients had ≥2+ mitral regurgitation. In mid systole, the distances between the LCX-RCA plane and the MAP in the four points were < 5 mm in 92% of patients. In mid diastole, distances were < 5 mm in 100% of patients. In mid systole, the correlation between the caudal/cranial orientations of the 2 planes was 0.85 and 0.80 in the LAO 90° and RAO 30°, respectively (P = <0.001). In mid diastole, this was 0.92 and 0.92 in the LAO 90° and RAO 30°, respectively (P = <0.001).
  
  
  CONCLUSIONS
  LCX-RCA plane has a close and consistent relationship to the MAP and can be useful to guide TMVI. Accurate imaging of mitral valve annular plane during TMVI procedure is challenging. MAP guided by fluoroscopy might be crucial to guide successful prosthesis deployment. A plane defined by the left circumflex- right coronary arteries in the atrioventricular grove has a consistent relationship with MAP; this can be used aided by pre-procedural MDCT to guide TMVI procedure. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic Foundation, Ohio.
authors.forename: Samir R
authors.initials: SR
authors.lastname: Kapadia
authors.affiliation: Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic Foundation, Ohio.
authors.forename: Amgad
authors.initials: A
authors.lastname: Mentias
authors.affiliation: Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic Foundation, Ohio.
authors.forename: Amr F
authors.initials: AF
authors.lastname: Barakat
authors.affiliation: Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic Foundation, Ohio.
authors.forename: Mohammad Q
authors.initials: MQ
authors.lastname: Raza
authors.affiliation: Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic Foundation, Ohio.
authors.forename: Kanhaiya
authors.initials: K
authors.lastname: Lal Poddar
authors.affiliation: Department of cardiovascular medicine, San Borja Arriaran Hospital, Cardiovascular Center, Santiago, Chile.
authors.forename: Cristian
authors.initials: C
authors.lastname: Baeza
authors.affiliation: Department of cardiovascular medicine, San Borja Arriaran Hospital, Cardiovascular Center, Santiago, Chile.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Maluenda
authors.affiliation: Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic Foundation, Ohio.
authors.forename: Jose
authors.initials: J
authors.lastname: Navia
authors.affiliation: Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic Foundation, Ohio.
authors.forename: Paul
authors.initials: P
authors.lastname: Schoenhagen
authors.affiliation: Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic Foundation, Ohio.
authors.forename: E
authors.initials: E
authors.lastname: Murat Tuzcu
mesh_terms: D000369:Aged, 80 and over; D059925:Anatomic Landmarks; D006328:Cardiac Catheterization / Q000379:methods*; D017023:Coronary Angiography / Q000379:methods; D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D005260:Female; D005471:Fluoroscopy; D005500:Follow-Up Studies; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D006801:Humans; D008297:Male; D008943:Mitral Valve / Q000000981:diagnostic imaging / Q000601:surgery*; D008944:Mitral Valve Insufficiency / Q000175:diagnosis / Q000601:surgery*; D061330:Multidetector Computed Tomography / Q000379:methods; D012189:Retrospective Studies; D025321:Surgery, Computer-Assisted / Q000379:methods*
keywords: cardiac computed tomography; mitral valve; mitral valve imaging; transcatheter mitral valve implantation