The high-risk features among patients undergoing mitral valve operation for ischemic mitral regurgitation: The 3-strike score

Objective Ischemic mitral regurgitation (iMR) is prevalent and is associated with high surgical risk. With the less-invasive option of transcatheter edge-to-edge repair, the optimal patient selection for mitral valve (MV) operation for iMR remains unclear. We sought to identify high-risk features in this group to guide patient selection. Methods Using the Cardiothoracic Surgery Trial Network’s severe iMR trial data, we identified patient and echocardiographic characteristics associated with an increased risk of 2-year mortality, using the support vector classifier and Cox proportional hazards model. We identified 6 high-risk features associated with 2-year survival. Patients were categorized into 3 groups, each having ≤1, 2, or ≥3 of the 6 identified high-risk features. Results Among the 251 patients, the median age was 69 (Q1 62, Q3 75) years, and 96 (38%) were female. Two-year mortality was 21% (n=53). We identified 6 high-risk preoperative features: age ≥75 (n=69, 28%), prior sternotomy (n=49, 20%), renal insufficiency (n=69, 28%), GI bleeding (n=15, 6%), LVEF<40% (n=131, 52%), and LVESVI<50ml/m2 (n=93, 37%). In patients who had ≤1, 2, and ≥3 high-risk features, 90-day mortality was 4.2% (n=5), 9.9% (n=4), and 20.0% (n=10), respectively (p=0.006), and two-year mortality was 10% (n=12), 22% (n=18), and 46% (n=23) (p<0.001), respectively. Conclusions We developed the 3-strike score by identifying high-risk preoperative features for MV surgery for iMR. Patients having 3 or more of such high-risk features should undergo careful evaluation for surgical candidacy given the high early and late mortality following MV operations.