Usefulness of SYNTAX score II in complex percutaneous coronary interventions in the setting of acute coronary syndrome

BackgroundSYNTAX score II (SS II) integrates anatomical SS with clinical characteristics allowing an individualized prediction of long-term mortality.AimsWe sought to assess to evaluate the usefulness of SS II in a real-world acute coronary syndromes (ACS) population with severe coronary artery disease (CAD) undergoing percutaneous coronary intervention (PCI).MethodsFrom August 2011 to May 2013, out of 1591 consecutive patients admitted for ACS, 217 (13.6%) showed severe CAD (three-vessel disease and/or left main involvement). Among the latter, 100 patients underwent PCI and were enrolled into the study. SS II was calculated in all patients. One-year clinical follow-up was performed; major adverse cardiac and cerebrovascular events (MACCE) were defined as a composite of death, nonfatal myocardial infarction, stroke, or repeat revascularization.ResultsThe median SS II was 29 (range, 14–59). Overall, MACCE occurred in 25% of patients (cardiac death 4%, myocardial infarction 4%, stroke 0%, and repeat revascularization 17%). The 1-year MACCE-free survival was significantly lower in patients with SS (⩾29), than in those with SS II (<29) (64.2% vs. 87.2%, respectively; p = 0.007). In multivariate Cox regression analysis, the presence of unprotected left main stenosis [hazard ratio 2.52, 95% confidence interval (CI): 1.02–5.85; p = 0.031] and SS II ⩾29 (hazard ratio 2.74, 95% CI: 1.30–8.21; p = 0.011) were the only predictors of MACCE at 1-year clinical follow-up. The c-index of SS score II was 0.70 (95% CI: 0.58–0.81). For patients who experienced MACCE, the SS II reclassification improved by 36%, while in nonevent patients the reclassification improved by 22%. The net reclassification index was 0.24 (p = 0.09).ConclusionSS II might represent a useful tool to predict clinical events in not only ideal stable patients, but also an unrestricted, real world population of patients with ACS and severe CAD undergoing PCI.