Treatment options for ischemic mitral regurgitation: A meta-analysis

Abstract

Background. Treatment of ischemic mitral regurgitation (IMR) is in evolution as percutaneous procedures and complex surgical repair have been recently investigated in randomized clinical trials and matched studies. This study aims to review and compare the current treatment options for IMR.Methods. A comprehensive literature search was conducted using electronic databases. The primary outcome was all-cause long-term mortality. The secondary outcomes were perioperative mortality, unplanned rehospitalization, reoperation, and composite endpoints as defined in the original articles.Results. A total of 12 articles met the inclusion criteria and were included in the final metaanalysis. The MitraClip procedure did not confer a significant benefit in mortality and repeated hospitalization compared to medical therapy alone. In patients with moderate IMR, the adjunct of mitral procedure over CABG is not associated with clinical improvements.When evaluating mitral valve (MV) replacement vs repair, hospital mortality was higher among patients undergoing replacement (OR 1.91, P=0.009), but both reoperation and readmission rates were lower (OR 0.60, P=0.05 and OR 0.45, P<0.02, respectively).Comparing restrictive annuloplasty alone with adjunctive subvalvular repair, subvalvular procedures resulted in fewer readmissions (OR 0.50, P=0.06) and adverse composite endpoints(P=0.009).Conclusions. MitraClip procedure is not associated with improved outcomes compared with medical therapy. MV replacement is associated with increased early mortality but reduced reoperation rate and readmission rate compared to MV repair using annuloplasty in moderateto-severe IMR. Despite no significant benefit in isolated outcomes comparing annular and adjunct subvalvular procedures, the adjunct of subvalvular procedures reduces the risk of major postoperative adverse events.

A right track stems from the right learning

“…Numerous studies have focused on the degree of annular restriction by mitral annuloplasty given the reported risk of stenosis, systolic anterior motion, and recurrent MR in overcorrection or excessive undersizing. [1][2][3][4][5][6][7][8][9] The anterior leaflet enlargement patch as performed by the authors is progressive 10 (Figure 1), provided that there is a marked reduction of tethering forces. 11,12 The forces on the fibrous skeleton of the heart exerted by annular undersizing would counteract the displacement vectors relative to the LV dilation expected in these patients.…”

Update on surgical repair in functional mitral valve regurgitation.

“…37 Intriguingly, an examination of the baseline characteristics of the patients participating in the 2 trials indicated that the studies included 2 distinctly different populations of patients with FMR. 45,46 Patients enrolled in the COAPT trial had more severe FMR (EROA 41mm 2 vs. 31mm 2 ; RVol 60ml vs. 45ml) and less dilated ventricles (LVEDV index 101ml/m 2 vs. 135ml/m 2 ) than those in the MITRA-FR trial. According to the concepts of proportionate and disproportionate MR, it is evident that the patients in the MITRA-FR trial represent a population in which the MR is proportional to the ventricular dilatation and is a consequence, not a cause, of the ventricular disease.…”

Commentary: Following the game-changers: Are we on the right track now?

“…To address this question, Nappi and colleagues 6 have conducted a timely meta-analysis. Along with analyzing the available surgical trials, their comprehensive systematic review also covers several important aspects, including rapidly-evolving transcatheter therapy-namely, the MitraClip intervention-and the latest clinical evidence on guideline-directed medical therapy.…”

“…On the one hand, we recognize that patients who had severe IMR following successful downsized annuloplasty (ie, without recurrence of MR) had the best clinical outcomes. 1,3,6 The well-proven principle "good repair is always better than good replacement" remains valid. Thus, restrictive annuloplasty as a useful tool could still be applied in some carefully selected patients.…”