title: Mitral valve repair or replacement for ischemic mitral regurgitation? The Italian Study on the Treatment of Ischemic Mitral Regurgitation (ISTIMIR).
abstract: OBJECTIVE
  It is uncertain whether mitral valve replacement is really inferior to mitral valve repair for the treatment of chronic ischemic mitral regurgitation. This multicenter study aimed at providing a contribution to this issue.
  
  
  METHODS
  Of 1006 patients with chronic ischemic mitral regurgitation and impaired left ventricular function (ejection fraction < 40%) operated on at 13 Italian institutions between 1996 and 2011, 298 (29.6%) underwent mitral valve replacement whereas 708 (70.4%) received mitral valve repair. Propensity scores were calculated by a nonparsimonious multivariable logistic regression, and 244 pairs of patients were matched successfully using calipers of width 0.2 standard deviation of the logit of the propensity scores. The postmatching median standardized difference was 0.024 (range, 0-0.037) and in none of the covariates did it exceed 10%.
  
  
  RESULTS
  Early deaths were 3.3% (n = 8) in mitral valve repair versus 5.3% (n = 13) in mitral valve replacement (P = .32). Eight-year survival was 81.6% ± 2.8% and 79.6% ± 4.8% (P = .42), respectively. Actual freedom from all-cause reoperation and valve-related reoperation were 64.3% ± 4.3% versus 80% ± 4.1%, and 71.3% ± 3.5% versus 85.5% ± 3.9 in mitral valve repair and mitral valve replacement, respectively (P < .001). Actual freedom from all valve-related complications was 68.3% ± 3.1% versus 69.9% ± 3.3% in mitral valve repair and mitral valve replacement, respectively (P = .78). Left ventricular function did not improved significantly, and it was comparable in the 2 groups postoperatively (36.9% vs 38.5%, P = .66). At competing regression analysis, mitral valve repair was a strong predictor of reoperation (hazard ratio, 2.84; P < .001).
  
  
  CONCLUSIONS
  Mitral valve replacement is a suitable option for patients with chronic ischemic mitral regurgitation and impaired left ventricular function. It provides better results in terms of freedom from reoperation with comparable valve-related complication rates.
authors.affiliation: Cardiac Surgery Unit, Community Hospital, Brescia, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Lorusso
authors.forename: Sandro
authors.initials: S
authors.lastname: Gelsomino
authors.forename: Enrico
authors.initials: E
authors.lastname: Vizzardi
authors.forename: Antonio
authors.initials: A
authors.lastname: D'Aloia
authors.forename: Giuseppe
authors.initials: G
authors.lastname: De Cicco
authors.forename: Fabiana
authors.initials: F
authors.lastname: Lucà
authors.forename: Orlando
authors.initials: O
authors.lastname: Parise
authors.forename: Gian Franco
authors.initials: GF
authors.lastname: Gensini
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Stefàno
authors.forename: Ugolino
authors.initials: U
authors.lastname: Livi
authors.forename: Igor
authors.initials: I
authors.lastname: Vendramin
authors.forename: Davide
authors.initials: D
authors.lastname: Pacini
authors.forename: Roberto
authors.initials: R
authors.lastname: Di Bartolomeo
authors.forename: Antonio
authors.initials: A
authors.lastname: Miceli
authors.forename: Egidio
authors.initials: E
authors.lastname: Varone
authors.forename: Mattia
authors.initials: M
authors.lastname: Glauber
authors.forename: Alessandro
authors.initials: A
authors.lastname: Parolari
authors.forename: Francesco
authors.initials: F
authors.lastname: Giuseppe Arlati
authors.forename: Francesco
authors.initials: F
authors.lastname: Alamanni
authors.forename: Filiberto
authors.initials: F
authors.lastname: Serraino
authors.forename: Attilio
authors.initials: A
authors.lastname: Renzulli
authors.forename: Antonio
authors.initials: A
authors.lastname: Messina
authors.forename: Giovanni
authors.initials: G
authors.lastname: Troise
authors.forename: Giovanni
authors.initials: G
authors.lastname: Mariscalco
authors.forename: Marzia
authors.initials: M
authors.lastname: Cottini
authors.forename: Cesare
authors.initials: C
authors.lastname: Beghi
authors.forename: Francesco
authors.initials: F
authors.lastname: Nicolini
authors.forename: Tiziano
authors.initials: T
authors.lastname: Gherli
authors.forename: Valentino
authors.initials: V
authors.lastname: Borghetti
authors.forename: Alessandro
authors.initials: A
authors.lastname: Pardini
authors.forename: Philippe-Primo
authors.initials: PP
authors.lastname: Caimmi
authors.forename: Ezio
authors.initials: E
authors.lastname: Micalizzi
authors.forename: Carlo
authors.initials: C
authors.lastname: Fino
authors.forename: Paolo
authors.initials: P
authors.lastname: Ferrazzi
authors.forename: Michele
authors.initials: M
authors.lastname: Di Mauro
authors.forename: Antonio Maria
authors.initials: AM
authors.lastname: Calafiore
mesh_terms: D000368:Aged; D002908:Chronic Disease; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation / Q000401:mortality; D006801:Humans; D007558:Italy; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D058386:Mitral Valve Annuloplasty / Q000009:adverse effects / Q000401:mortality; D008944:Mitral Valve Insufficiency / Q000209:etiology / Q000401:mortality / Q000503:physiopathology / Q000601:surgery*; D015999:Multivariate Analysis; D017202:Myocardial Ischemia / Q000150:complications* / Q000401:mortality / Q000503:physiopathology; D011183:Postoperative Complications / Q000209:etiology / Q000601:surgery; D057216:Propensity Score; D016016:Proportional Hazards Models; D011474:Prosthesis Design; D012086:Reoperation; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013318:Stroke Volume; D013997:Time Factors; D016896:Treatment Outcome; D016277:Ventricular Function, Left