title: Elongation of chordae tendineae as an adaptive process to reduce mitral regurgitation in functional mitral regurgitation.
abstract: OBJECTIVE
  In functional mitral regurgitation (FMR), increased leaflet area has been described as a remodelling compensatory mechanism. We hypothesized that chordae tendineae elongation would also occur as part of this remodelling. In this study, the lengths of primary chords and measurements of mitral leaflets and annulus were compared with varying degrees of mitral regurgitation (MR).
  
  
  RESULTS
  We studied 58 patients who underwent three-dimensional (3D) transoesophageal echocardiography, including 38 with FMR and 20 with normal mitral valves (NL). The FMR group was divided into two subgroups according to two-dimensional vena contracta width (VCW). Three-dimensional datasets from transgastric or mid-oesophageal approach were used to measure primary chordal length, coaptation length, inter-papillary muscle distances, and quantitative 3D measurements of the annulus and leaflets. Leaflet surface area was increased and coaptation length was decreased in FMR compared with NL. While no difference in other 3D measurement of annulus/leaflets was noted between the FMR subgroups, averaged chordal length was shorter in patients with more severe FMR. Chords of the anterior leaflet in FMR with larger VCW were shorter compared with both NL and FMR with smaller VCW. In contrast, the chords of the posterior leaflet were longer in FMR with smaller VCW compared with the other two groups.
  
  
  CONCLUSIONS
  Our results suggest the posterior leaflet chords possibly remodel by elongating and contribute to reduced MR and that in a subgroup of FMR patients, the primary chords may remodel by shortening, resulting in augmented MR. This information could be useful in choosing strategy for FMR correction.
authors.affiliation: Noninvasive Cardiac Imaging Laboratory, Section of Cardiology, Department of Medicine, University of Chicago Medical Center, 5841 S. Maryland Avenue, Chicago, IL 60637, USA Department of Cardiology, Kawasaki Medical School, Kurashiki, Japan.
authors.forename: Kikuko
authors.initials: K
authors.lastname: Obase
authors.affiliation: Noninvasive Cardiac Imaging Laboratory, Section of Cardiology, Department of Medicine, University of Chicago Medical Center, 5841 S. Maryland Avenue, Chicago, IL 60637, USA.
authors.forename: Lynn
authors.initials: L
authors.lastname: Weinert
authors.affiliation: Department of Anesthesia and Critical Care, University of Chicago, Chicago, IL, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Hollatz
authors.affiliation: Department of Anesthesia and Critical Care, University of Chicago, Chicago, IL, USA.
authors.forename: Farhan
authors.initials: F
authors.lastname: Farooqui
authors.affiliation: Department of Anesthesia and Critical Care, University of Chicago, Chicago, IL, USA.
authors.forename: Joseph D
authors.initials: JD
authors.lastname: Roberts
authors.affiliation: Department of Anesthesia and Critical Care, University of Chicago, Chicago, IL, USA.
authors.forename: Mohammed M
authors.initials: MM
authors.lastname: Minhaj
authors.affiliation: Department of Anesthesia and Critical Care, University of Chicago, Chicago, IL, USA.
authors.forename: Avery
authors.initials: A
authors.lastname: Tung
authors.affiliation: Department of Anesthesia and Critical Care, University of Chicago, Chicago, IL, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Chaney
authors.affiliation: Cardiovascular Surgery, University of Chicago, Chicago, IL, USA.
authors.forename: Takeyoshi
authors.initials: T
authors.lastname: Ota
authors.affiliation: Cardiovascular Surgery, University of Chicago, Chicago, IL, USA.
authors.forename: Valluvan
authors.initials: V
authors.lastname: Jeevanandam
authors.affiliation: Department of Cardiology, Kawasaki Medical School, Kurashiki, Japan.
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Yoshida
authors.affiliation: Noninvasive Cardiac Imaging Laboratory, Section of Cardiology, Department of Medicine, University of Chicago Medical Center, 5841 S. Maryland Avenue, Chicago, IL 60637, USA.
authors.forename: Victor
authors.initials: V
authors.lastname: Mor-Avi
authors.affiliation: Noninvasive Cardiac Imaging Laboratory, Section of Cardiology, Department of Medicine, University of Chicago Medical Center, 5841 S. Maryland Avenue, Chicago, IL 60637, USA rlang@medicine.bsd.uchicago.edu.
authors.forename: Roberto M
authors.initials: RM
authors.lastname: Lang
mesh_terms: D000328:Adult; D000368:Aged; D002815:Chordae Tendineae / Q000000981:diagnostic imaging*; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008944:Mitral Valve Insufficiency / Q000000981:diagnostic imaging* / Q000503:physiopathology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity
keywords: adaptation; chordae tendineae; functional mitral regurgitation