Ischemic mitral regurgitation (IMR) remains one of the most challenging scenarios in valvular surgery, since it reflects ventricular remodeling after ischemic heart disease rather than a primary disorder of the mitral valve itself. Mitral valve repair (MVr) using restrictive annuloplasty combined with coronary artery bypass grafting (CABG) is a widely adopted strategy for patients with moderate or moderate-to-severe IMR, yet questions remain about how durable this approach is and which factors shape long-term outcomes. Here, the authors report a single-center experience spanning two decades, examining survival and the predictors of mortality associated with this combined surgical strategy.

This retrospective observational study enrolled 212 patients with chronic moderate or moderate-to-severe IMR who underwent MVr with restrictive annuloplasty plus CABG between January 2005 and May 2025, all with significant coronary artery disease. Mean age was 60.5 ± 8.7 years; 52.8% had diabetes, 67% had hypertension, and 64.6% had three-vessel disease. Mean left ventricular ejection fraction (LVEF) was 46.6 ± 10.2%, and baseline left ventricular end-systolic diameter (LVESD) averaged 40.9 ± 5.6 mm. Clinical follow-up extended remarkably to 20 years.

Thirty-day mortality was 1.4%, with Kaplan-Meier estimated survival of 97.6% at 1 year, 94.3% at 5 years, 88.7% at 10 years, 87.3% at 12 years, and 81.1% at 20 years. Complete revascularization was achieved in 91.5% of patients, with a mean of 2.8 ± 0.9 grafts per case. After repair, 29 patients (13.7%) had mild residual mitral regurgitation (MR), while the remaining 183 (86.3%) had no residual MR. Patients with more-than-mild residual MR were converted intraoperatively to mitral valve replacement and were excluded from the analyzed cohort. On echocardiography, LVEF remained broadly stable throughout follow-up (46.5% preoperatively versus 47.1% at the end of follow-up; p = .202).

Survival analysis showed that diabetes mellitus, residual MR after repair, incomplete revascularization, and an LVESD of 45 mm or greater were each linked to reduced survival on univariate analysis. After multivariable adjustment, however, residual MR (even when mild) and incomplete revascularization stood out as the only independent predictors of mortality at 12 years. When follow-up was extended to 20 years, an LVESD of 45 mm or greater emerged as a third independent adverse prognostic factor. Age above 65 years, sex, baseline LVEF below 40%, and preoperative renal dysfunction showed no significant effect on survival.

Taken together, these findings indicate that MVr with restrictive annuloplasty combined with CABG yields excellent long-term survival in carefully selected patients. The durability of this strategy rests on three surgical pillars: eliminating residual MR before leaving the operating room, achieving complete revascularization, and intervening early, before ventricular remodeling reaches an advanced stage.

COMMENTARY:

This study raises a central question: does the success of MVr rest mainly on surgical technique, or, more fundamentally, on proper patient selection? Surgery for IMR begins well before the patient reaches the operating room.

Choosing between repair and mitral valve replacement is not simply a matter of leaflet or annular anatomy; it requires understanding the underlying ventricular disease. Unlike degenerative etiology, where the lesion originates within the valve apparatus itself, IMR arises from adverse ventricular remodeling driven by ischemic heart disease. Papillary muscle displacement, annular dilation, and increased leaflet tethering forces disrupt coaptation, turning the valve into the expression of a disease whose principal driver is the left ventricle (LV).

This pathophysiologic complexity explains why the optimal surgical approach remains contested. For decades the debate centered on whether MVr could match mitral valve replacement, particularly once trials reported high rates of recurrent MR within two years of restrictive annuloplasty. Framing the discussion as a binary choice between the two techniques, however, oversimplifies matters. How durable a repair proves to be; depends on baseline ventricular geometry, the severity of tethering, myocardial viability, whether complete revascularization can be achieved, and how much MR remains once the operation is finished.

Against this backdrop, the work by Sajja and colleagues stands out for the length of its follow-up and for how favorable its results are. An estimated 20-year survival of 81.1% seems remarkable for a population with ischemic heart disease and secondary MR. Still, these figures call for cautious interpretation, since they come from a highly selected cohort. The protocol excluded patients with severe MR, organic valve disease, prior valve or coronary surgery, and more-than-mild residual MR after repair; moreover, every patient whose intraoperative residual MR exceeded mild was converted to mitral valve replacement. The results therefore do not describe how IMR behaves in general, but rather the prognosis achievable in candidates for whom an optimal outcome was attainable.

This is both a methodological limitation and one of the study’s key lessons. The series does not show that MVr should be applied universally; rather, it can be an effective strategy when patient selection is sound and the intraoperative result is optimal. Without a contemporaneous group treated with mitral valve replacement, direct comparison between the two approaches is not possible. Likewise, being retrospective, single-center, and spanning two decades leaves the series open to selection bias and to shifts over time in CABG technique, myocardial protection, echocardiographic assessment, and medical management of ischemic heart disease.

How residual MR was defined also warrants caution: the study classified any degree of persistent regurgitation as residual, though only patients with trivial or mild insufficiency remained in the cohort. The strong link between this variable and long-term mortality is clinically meaningful, but it does not by itself establish causation. Residual MR may simply mark a less effective repair, or it may instead reflect a more unfavorable ventricular geometry, greater leaflet tethering, or myocardium with less capacity for reverse remodeling. Even so, the practical takeaway is clear: accepting a suboptimal repair in IMR can undercut the expected benefit and should prompt immediate reconsideration of the surgical strategy.

Coronary revascularization stands out as the second major determinant of survival. This finding is a reminder that MVr should not be viewed as an isolated valve procedure but as one component of a comprehensive strategy aimed at treating the underlying ischemic disease. How completely revascularization is achieved shapes not only myocardial perfusion but also the trajectory of ventricular remodeling, and with it, how long a repair will last.

The third independent predictor of 20-year mortality was an LVESD of 45 mm or greater. This underscores the need to operate before remodeling advances to an irreversible stage. While LVESD should not be treated as a single universal cutoff, it serves as an important warning sign within a broader, multidimensional echocardiographic assessment.

By contrast, it is notable that a preoperative LVEF below 40% was not independently linked to a worse prognosis. This does not diminish the relevance of systolic function; LVEF is heavily load-dependent and can overstate contractile reserve when significant MR is present. Small subgroup numbers may also have limited statistical power. Ventricular dimensions and mitral apparatus geometry likely add prognostic information beyond LVEF alone, particularly in a disease where the mechanism of regurgitation is so closely tied to remodeling.

For clinical practice, the real value of this work lies not in proving MVr superior to mitral valve replacement (its design cannot support that claim),  but in clarifying the conditions under which repair can deliver durable results. MVr looks reasonable when ventricular remodeling is not yet far advanced, complete CABG is achievable, and effective coaptation without meaningful residual MR can be obtained. Conversely, when ventricular geometry is markedly unfavorable, tethering is severe, or the likelihood of recurrence is high, mitral valve replacement with subvalvular preservation may offer a more predictable outcome.

Perhaps the central lesson from these two decades of experience is that success in ischemic mitral surgery does not hinge simply on which ring is implanted or what size is chosen. It hinges on recognizing which patients have a ventricle still capable of benefiting from complete revascularization and of sustaining a durable repair. Intraoperative echocardiography is indispensable, but genuine patient selection starts earlier, in the assessment of coronary anatomy, myocardial viability, ventricular remodeling, and the subvalvular apparatus. Ultimately, beyond the operating room, this work reminds us that correctly repairing a valve is not enough; the ventricular disease that made it insufficient must also be understood and treated.

REFERENCE:

Sajja LR, Mannam G, Koppula A, Dandu SBR, Pathuri S, Krishnamurthy VSSS, et al. Outcomes of mitral valve repair in ischemic mitral regurgitation: A two-decade experience. JTCVS Open. 2026 Apr 2;31:101743. doi: 10.1016/j.xjon.2026.101743.