Asymmetric Ring Annuloplasty for Ischemic Mitral Regurgitation: Early and Mid-Term Outcomes

Background and aim of the study: The Carpentier-McCarthy-Adams IMR ETlogix (R) annuloplasty ring was specifically designed to treat ischemic mitral regurgitation (IMR) associated with asymmetric mitral annular dilation and leaflet tethering. The study aim was to review, retrospectively, the results of mitral annuloplasty with this asymmetric ring in a representative number of patients. Methods: Between January 2005 and July 2012, the IMR ETlogix ring was implanted in 190 consecutive patients (mean age 69.5 +/- 7.6 years) with grade >= 2+ IMR (graded from 0 to 3+). Preoperatively, 37 patients (19.5%) were in NYHA class IV, and 73 (38.4%) suffered from unstable angina. The operative risk according to the European System for Cardiac Operative Risk Evaluation II was 15.6 +/- 14.5%. Using two-dimensional echocardiography, postoperative changes in mitral annular diameter (MAD) and tenting height (TH) of the mitral valve in four-chamber, two-chamber and long-axis views, were assessed at mid-systole. Results: Thirty-eight patients (20.0%) received one or more concomitant major cardiac surgical procedure(s) other than, or in addition to, coronary artery bypass grafting or tricuspid valve annuloplasty. Nineteen (10.0%) hospital deaths occurred, and one patient underwent immediate reoperation for residual MR. During the follow up (mean 4.8 +/- 2.1 years) there were 26 cardiac deaths, 14 non-cardiac deaths, and three mitral valve replacements. The seven-year actuarial survival, freedom from grade >= 2+ MR and reoperation were 62.0%, 93.1% and 97.6%, respectively. Renal impairment (p = 0.012) and extracardiac arteriopathy (p = 0.047) were predictors of death; bilateral internal thoracic artery grafting was a protective factor (p = 0.033). Heart failure symptoms were improved (p<0.01). Left ventricular reverse remodeling was achieved in 50.6% of patients. The MAD and TH were each decreased in all three echocardiographic views (p<0.001), the reductions being greater in the long-axis view. Conclusion: By restoring the mitral apparatus geometry and competence, asymmetric annuloplasty with the IMR ETlogix ring provides good mid-term outcomes and helps left ventricular reverse remodeling in IMR.