title: The extent of papillary muscle approximation affects mortality and durability of mitral valve repair for ischemic mitral regurgitation.
abstract: BACKGROUND
  Since reduction annuloplasty alone for ischemic mitral regurgitation (MR) cannot prevent late recurrence of MR or improve survival for those with left ventricular (LV) dysfunction, and the surgical approach to this etiology is still controversial, we conducted a study to assess the efficacy of the additional papillary muscle approximation (PMA) procedure for ischemic MR by comparing the different subtypes of PMA.
  
  
  METHODS
  We studied 45 patients who underwent mitral annuloplasty and papillary muscle approximation (PMA) for ischemic MR between 2003 and 2012. Papillary muscles were approximated entirely (cPMA: complete PMA, n = 32) through an LV incision or partially from the tips to mid-parts (iPMA: incomplete PMA, n = 13) through the mitral and aortic valves. Twenty-three patients with cPMA also underwent LV plasty (LVP). We assessed the outcomes after PMA by comparing cPMA and iPMA.
  
  
  RESULTS
  The baseline MR grade, NYHA class, LV end-diastolic diameter, and LV ejection fraction (LVEF) were 2.8 ± 1.0, 3.2 ± 0.6, 67 ± 6 mm, and 30 ± 10%, respectively. There were no significant differences in these parameters among those with iPMA, cPMA/LVP-, and cPMA/LVP+, though iPMA patients had better LVEF than others. Three patients died before discharge and 12 died during the follow-up. Recurrence of grade 2+ and 3+ MR occurred in 8 and 2 patients, respectively. Reoperation for recurrent MR was performed only for the 2 patients with recurrence of grade 3+ MR. The cPMA was associated with lower mortality (log-rank P = 0.020) and a lower rate of recurrence of MR ≥2+ (log-rank P = 0.005) than iPMA. In contrast, there were no significant differences in the mortality (log-rank P = 0.45) and rate of recurrence (log-rank P = 0.98) between those with cPMA/LVP- and cPMA/LVP+. The 4-year survival rate and rate of freedom from recurrence of MR ≥2+ were 83% and 85% for those with cPMA, repectively. In contrast, the rates were 48% and 48% for those with iPMA, respectively.
  
  
  CONCLUSIONS
  Complete PMA could be associated with lower postoperative mortality and higher durability of mitral valve repair for ischemic MR.
authors.forename: Satoru
authors.initials: S
authors.lastname: Wakasa
authors.forename: Suguru
authors.initials: S
authors.lastname: Kubota
authors.forename: Yasushige
authors.initials: Y
authors.lastname: Shingu
authors.forename: Tomonori
authors.initials: T
authors.lastname: Ooka
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Tachibana
authors.affiliation: Department of Cardiovascular and Thoracic Surgery, Hokkaido University Graduate School of Medicine, Kita-15, Nishi-7, Kita-ku, Sapporo 060-8638, Japan. ymatsui@med.hokudai.ac.jp.
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Matsui
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D058385:Cardiac Valve Annuloplasty / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006352:Heart Ventricles / Q000601:surgery*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000150:complications / Q000401:mortality / Q000601:surgery*; D017202:Myocardial Ischemia / Q000150:complications / Q000401:mortality / Q000601:surgery*; D010210:Papillary Muscles / Q000601:surgery*; D011184:Postoperative Period; D012008:Recurrence; D012189:Retrospective Studies; D015996:Survival Rate / Q000639:trends