Baseline left ventricular function and surgical annular stiffening to predict outcome and reverse left ventricular remodeling after undersized annuloplasty for intermediate-degree ischemic mitral regurgitation
Received 5 February 2009; received in revised form 25 July 2009; accepted 23 August 2009. published online 07 December 2009.
Objective
We sought to identify determinants of clinical and functional outcome after myocardial revascularization and associated undersized annuloplasty in patients with intermediate-degree ischemic mitral regurgitation.
Methods
Fifty-seven patients with 2+ or 3+ ischemic mitral regurgitation underwent coronary bypass surgery and implantation of undersized semirigid or flexible complete ring or autologous pericardial band and were followed up to 8.6 years.
Results
Operative mortality was 5%. Baseline left ventricular end-systolic volume index, the strongest multivariable predictor of early postoperative outcome, was correlated with end-systolic volume index (P < .001, R2 = 0.67) and ejection fraction (P < .001, R2 = 0.40) after repair. More compromised ejection fraction and end-systolic volume index predicted comparatively greater early functional improvement but higher residual postoperative end-systolic volume index (P < .01). Cox multivariable analysis identified wall motion as the best baseline predictor of late death and heart failure and regional inferoposterior wall motion as the strongest predictor of recurrent mitral regurgitation (P ≤ .01). More rigid annuloplasty carried a higher probability of functional recovery in terms of ejection fraction, wall motion, and the occurrence and earlier timing of left ventricular reverse remodeling, expressed by different degrees of end-systolic volume index reduction (P < .001, hazard ratio >6).
Conclusions
Combination of undersized mitral annuloplasty and coronary revascularization presents low operative mortality and determines left ventricular unloading in patients with intermediate-degree ischemic mitral regurgitation. Global and regional wall motion are powerful predictors of late outcome. Stiffer mitral annular repair promotes functional recovery and predicts higher probability and earlier timing of reverse remodeling.
Department of Cardiovascular Sciences, University of Milan, Milan, Italy
Address for reprints: Marco Pocar, MD, PhD, Dipartimento di Scienze Cardiovascolari, Università degli Studi di Milano, IRCCS MultiMedica, Via Milanese 300, 20099 Sesto San Giovanni, Milano, Italy.
ABSTRACT