title: The Influence of Mitral Annuloplasty on Left Ventricular Flow Dynamics.
abstract: BACKGROUND
  Mitral valve (MV) repair using annuloplasty rings is the preferred method of treatment for MV regurgitation, but the impact of annuloplasty ring placement on left ventricular intraventricular flow has not been studied.
  
  
  METHODS
  Annuloplasty rings of varying sizes were placed in 5 healthy sheep (intercommissural ring sizes were 24, 26, 28, 30, and 32 mm), and three-dimensional phase contrast magnetic resonance imaging (4D flow MRI) was performed before and 1 week after ring placement.
  
  
  RESULTS
  Normal diastolic flow consisted of diastolic intraventricular vortices that naturally unwound during systole. Postsurgical intraventricular flow was highly disturbed in all sheep, and the disturbance was greatest for undersized rings. Ring size was highly correlated with the diastolic inflow angle (Pearson's r = -0.62, p < 0.1, 95% confidence interval: -0.92 to 0.14). There was a mean angle increase of mean diastolic inflow angle increase of 12.3 degrees (< 30 mm, p < 0.01, 95% confidence interval: 4.8 to 19.6) for rings less than 30 mm. There was an inverse relationship between peak velocity and annuloplasty ring area (Pearson's r = -0.80, p < 0.05, 95% confidence interval: -0.96 to -0.2). Transmitral pressure gradients increased significantly from baseline 0.73 ± 0.18 mm Hg to after annuloplasty 2.31 ± 1.04 mm Hg (p < 0.05).
  
  
  CONCLUSIONS
  Mitral valve annuloplasty ring placement disturbs normal left ventricular intraventricular flow patterns, and the degree of disturbance is closely associated with annuloplasty ring size.
authors.affiliation: Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Walter Rt
authors.initials: WR
authors.lastname: Witschey
authors.affiliation: Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Donald
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Francisco
authors.initials: F
authors.lastname: Contijoch
authors.affiliation: Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Jeremy R
authors.initials: JR
authors.lastname: McGarvey
authors.affiliation: Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Madonna
authors.initials: M
authors.lastname: Lee
authors.affiliation: Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Takebayashi
authors.affiliation: Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Chikashi
authors.initials: C
authors.lastname: Aoki
authors.affiliation: Cardiovascular Division, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Yuchi
authors.initials: Y
authors.lastname: Han
authors.affiliation: Cardiovascular Division, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Joyce
authors.initials: J
authors.lastname: Han
authors.affiliation: Northwestern University, Chicago, IL, USA.
authors.forename: Alex J
authors.initials: AJ
authors.lastname: Barker
authors.affiliation: Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: James J
authors.initials: JJ
authors.lastname: Pilla
authors.affiliation: Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Gorman
authors.affiliation: Gorman Cardiovascular Research Group, University of Pennsylvania, Philadelphia, PA, USA.
authors.forename: Joseph H
authors.initials: JH
authors.lastname: Gorman
mesh_terms: D000818:Animals; D006439:Hemodynamics; D058386:Mitral Valve Annuloplasty; D012039:Regional Blood Flow; D012756:Sheep; D016277:Ventricular Function, Left