Comparison Between the NERS (New Risk Stratification) Score and the SYNTAX (Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) Score in Outcome Prediction for Unprotected Left Main Stenting

Abstract

This study aimed to compare the NERS (New Risk Stratification) and SYNTAX (Synergy between Percutaneous Coronary Intervention with Taxus and Cardiac Surgery) scores for prognostication after stenting of unprotected left main stenosis in a "real-world" setting. In contrast to existing systems, the NERS score encompasses clinical, procedural, and angiographic characteristics. The NERS score was derived from 260 patients with unprotected left main stenosis who underwent percutaneous coronary intervention and tested in 337 patients in a consecutive left main registry (66.55 +/- 10.49 years, 78.9% men) undergoing percutaneous coronary intervention in a prospective, multicenter trial. Six-month clinical and angiographic follow-up was obtained in 100% and 88.9% of patients, respectively. The primary end point was major adverse cardiac events (MACE), encompassing myocardial infarction, all-cause death, and target vessel revascularization. Receiver-operator characteristic (ROC) curve was generated for the comparison of NERS versus SYNTAX scores. The NERS score consisted of 54 variables (17 clinical, 4 procedural, and 33 angiographic). A NERS score > or =25 demonstrated a sensitivity and specificity of 92.0% and 74.1% (MACE as state variable), respectively, significantly higher than SYNTAX intermediate risk (20.5% and 25.4%) or SYNTAX higher risk (70.5% and 35.2%, p for all <0.001). At follow-up, myocardial infarction, cardiac death, and target vessel revascularization occurred in 3.0%, 5.6%, and 13.1% of patients, respectively, for a composite MACE of 26.0%. A NERS score > or =25 (hazard ratio: 1.13; 95% confidence interval [CI]: 1.11 to 1.16; p < 0.001) was the only independent predictor of cumulative MACE and stent thrombosis at follow-up (odds ratio: 31.04; 95% CI: 19.36 to 67.07; p < 0.001). The NERS score was more predictive of MACE than the SYNTAX score was. Further study is needed to address their relative roles in assessment for appropriateness of coronary artery bypass graft versus percutaneous coronary intervention for unprotected left main coronary artery stenosis.