Survival after coronary artery bypass grafting with or without mitral valve repair for moderate ischemic mitral regurgitation
L Chen, X Tiemuerniyazi, W Zhao, W FengAbstract
Background
The surgical management of moderate ischemic mitral regurgitation (IMR) in patients undergoing coronary artery bypass grafting (CABG) remains controversial, with limited real-world evidence, particularly from Asian populations.
Purpose
To compare long-term clinical outcomes and echocardiographic changes between isolated CABG and CABG with concomitant mitral valve repair (MVr) in patients with coronary artery disease and moderate IMR.
Methods
We retrospectively analyzed 650 patients with moderate IMR who underwent isolated CABG (n=493) or CABG with MVr (n=157) between August 2009 and April 2024. Inverse probability of treatment weighting was applied to adjust for baseline differences. The primary endpoint was all-cause mortality. The secondary endpoint was major adverse cardiovascular and cerebrovascular events (MACCE), defined as a composite of all-cause death, non-fatal myocardial infarction, non-fatal stroke, repeat revascularization, repeat mitral valve surgery, and rehospitalization for heart failure.
Results
During a median follow-up of 36.6 months, CABG with MVr was associated with lower all-cause mortality (multivariable HR, 0.41; 95% CI, 0.22-0.79; weighted log-rank P=0.006) and fewer MACCE (weighted log-rank P=0.001), mainly driven by fewer deaths and rehospitalizations for heart failure. Findings were consistent across sensitivity and subgroup analyses. At echocardiographic follow-up (median, 11.6 months), CABG with MVr showed greater improvement in mitral regurgitation (75.4% vs 50.4%, P<0.001) and a larger reduction in left ventricular end-diastolic diameter (4.0 [0.0, 7.8] vs 3.0 [-1.0, 6.0], P=0.026). CABG with MVr was associated with longer postoperative intubation, longer intensive care unit stay, and an increased risk of acute kidney injury, without increased early mortality.
Conclusions
In one of the largest Asian real-world cohorts, concomitant MVr during CABG for moderate IMR was associated with lower mortality, fewer MACCE, and greater echocardiographic improvement, but at the expense of increased perioperative morbidity.FigureFor image description, please refer to the figure legend and surrounding text.