title: Relationship between the magnitude of reduction in mitral regurgitation severity and left ventricular and left atrial reverse remodeling after MitraClip therapy.
abstract: BACKGROUND
  MitraClip has been shown to reduce mitral regurgitation (MR) severity safely but to a lesser degree than surgery. No data exist on the magnitude of MR reduction necessary to reverse left ventricular (LV) and left atrial (LA) dilation in patients with severe MR. Therefore, an analysis was performed to evaluate the relationship between MR reduction and LV and LA volumes after MitraClip therapy.
  
  
  RESULTS
  A total of 801 patients treated with MitraClip and 80 patients treated surgically were included. All patients had severe (3-4+) MR. MR severity, LV volumes at end-diastole and end-systole, and LA volumes were measured at baseline, discharge, 30 days, 6 months, and 1 year by an independent echocardiographic core laboratory. A linear repeated measures model was developed to determine the relationship between MR severity and time of measurement postindex procedure on longitudinal LV and LA volumes. Separate models were fit for functional MR and degenerative MR. In both degenerative and functional MR, reduction in LV volumes at end-diastole was associated with degree of residual MR at 12 months (P<0.0001). LV volumes at end-systole was significantly reduced in functional MR but not degenerative MR. LA volumes were significantly related to reduction of MR severity in both groups.
  
  
  CONCLUSIONS
  Reduction of LV volumes at end-diastole and LA volumes, but not LV volumes at end-systole in degenerative MR, is consistent with correction of volume overload from primary MR. Reduction of all 3 measurements in functional MR demonstrates reverse remodeling when MR severity is reduced to either 1+ or 2+ by MitraClip therapy.
  
  
  BACKGROUND
  http://www.clinicaltrials.gov. Unique identifier: NCT00209274.
authors.affiliation: Baylor University Medical Center, Baylor Heart and Vascular Institute, Dallas, TX (P.A.G.); University of California, San Francisco (E.F.); Abbott Vascular Structural Heart, Menlo Park, CA (C.S.); MedStar Health Research Institute, Washington, DC (N.J.W.); Boston University School of Public Health, Harvard Clinical Research Institute, Boston, MA (J.M.); Duke University Medical Center, Durham, NC (D.G.G.); Evanston Hospital, NorthShore University Health System, Evanston, IL (T.F.); and Brigham and Women's Hospital, Harvard Clinical Research Institute, Harvard Medical School, Boston, MA (L.M.).
authors.forename: Paul A
authors.initials: PA
authors.lastname: Grayburn
authors.forename: Elyse
authors.initials: E
authors.lastname: Foster
authors.forename: Chithra
authors.initials: C
authors.lastname: Sangli
authors.forename: Neil J
authors.initials: NJ
authors.lastname: Weissman
authors.forename: Joseph
authors.initials: J
authors.lastname: Massaro
authors.forename: Donald G
authors.initials: DG
authors.lastname: Glower
authors.forename: Ted
authors.initials: T
authors.lastname: Feldman
authors.forename: Laura
authors.initials: L
authors.lastname: Mauri
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D064752:Atrial Remodeling / Q000502:physiology*; D002306:Cardiac Volume / Q000502:physiology; D005260:Female; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery*; D012720:Severity of Illness Index; D016896:Treatment Outcome; D014463:Ultrasonography; D020257:Ventricular Remodeling / Q000502:physiology*
keywords: heart valves; mitral valve insufficiency; ventricular remodeling