title: Quantification of mitral regurgitation by real time three-dimensional color Doppler flow echocardiography pre- and post-percutaneous mitral valve repair.
abstract: BACKGROUND
  Echocardiographic quantification of mitral regurgitation (MR) can be challenging if the valve geometry is significantly altered. Our aim was to compare the quantification of MR by the recently developed real time three-dimensional (3D) volume color flow Doppler (RT-VCFD) method to the conventional two-dimensional (2D) echocardiographic methods during the MitraClip procedure.
  
  
  METHODS
  Twenty-seven patients (mean age 76 ± 8 years, 56% male) were prospectively enrolled and severity of MR was assessed before and after the MitraClip procedure in the operating room by 3 different methods: (1) by integrative visual approach by transesophageal echocardiography, (2) by transthoracic 2D pulsed-wave Doppler-based calculation of aortic stroke volumes (SV) and mitral inflow allowing calculation of regurgitant volume, and (3) by transthoracic 3D RT-VCFD-based calculation of regurgitant volume.
  
  
  RESULTS
  We found moderate agreement between the integrative visual approach and the 3D RT-VCFD method for assessment of MR severity before (κ = 0.4, P < 0.05) and after MitraClip (κ = 0.5, P < 0.05). Relevant MR (3+ and 4+) was detected by visual approach in 27/27 and by 3D-VCFD method in 24/27 patients before and in 1 patient by both methods after the MitraClip procedure. In contrast, MR quantification by 2D SV method did not agree with the integrative visual approach or with the 3D RT-VCFD method.
  
  
  CONCLUSIONS
  Quantification of MR before and after percutaneous MV repair by 3D RT-VCFD is comparable to the integrative visual assessment and more reliable than the 2D SV method in this small study population. Further automation of 3D RT-VCFD is needed to improve the accuracy of peri-interventional MR quantification.
authors.affiliation: Echocardiography Laboratory, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Christiane
authors.initials: C
authors.lastname: Gruner
authors.affiliation: Echocardiography Laboratory, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Herzog
authors.affiliation: Department of Anesthesiology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Dominique
authors.initials: D
authors.lastname: Bettex
authors.affiliation: Department of Anesthesiology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Felix
authors.affiliation: Siemens Medical Solutions USA Inc., Mountain View, California.
authors.forename: Saurabh
authors.initials: S
authors.lastname: Datta
authors.affiliation: Echocardiography Laboratory, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Matthias
authors.initials: M
authors.lastname: Greutmann
authors.affiliation: Andreas Grüntzig Cardiac Catheterization Laboratory, Cardiology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Oliver
authors.initials: O
authors.lastname: Gaemperli
authors.affiliation: Department of Internal Medicine, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Simon A
authors.initials: SA
authors.lastname: Müggler
authors.affiliation: Echocardiography Laboratory, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Felix C
authors.initials: FC
authors.lastname: Tanner
authors.affiliation: Cardiovascular Surgery, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Juerg
authors.initials: J
authors.lastname: Gruenenfelder
authors.affiliation: Andreas Grüntzig Cardiac Catheterization Laboratory, Cardiology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Roberto
authors.initials: R
authors.lastname: Corti
authors.affiliation: Echocardiography Laboratory, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Patric
authors.initials: P
authors.lastname: Biaggi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018618:Echocardiography, Doppler, Color; D019560:Echocardiography, Three-Dimensional; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000601:surgery; D011182:Postoperative Care; D011300:Preoperative Care; D011446:Prospective Studies; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013318:Stroke Volume
keywords: MitraClip; mitral regurgitation; percutaneous mitral valve repair; real time three-dimensional color Doppler flow echocardiography