Global Risk Classification and Clinical SYNTAX (Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery) Score in Patients Undergoing Percutaneous or Surgical Left Main Revascularization

Abstract

The aim of this study was to investigate the ability to predict cardiac mortality of the Global Risk Classification (GRC) and the Clinical SYNTAX (Synergy between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery) score (CSS) in left main (LM) patients undergoing percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG). There is a renewed interest in combining clinical and angiographic information to define the risk of patients undergoing LM revascularization. The GRC and CSS were assessed in patients undergoing LM PCI (n = 400) or CABG (n = 549). Stand-alone clinical (ACEF [age, creatinine, ejection fraction]), EuroSCORE (European System for Cardiac Operative Risk Evaluation) and angiographic (SYNTAX score) risk scores were also investigated. The GRC (Hosmer-Lemeshow statistic 0.357, p = 0.550; area under the curve 0.743) and the ACEF (Hosmer-Lemeshow 0.426, p = 0.514; area under the curve 0.741) showed the most balanced predictive characteristics in the PCI and CABG cohorts, respectively. In PCI patients, the CSS used fewer data to achieve similar discrimination but poorer calibration than the GRC. Propensity-adjusted outcomes were comparable between PCI and CABG patients with low, intermediate, or high EuroSCORE, ACEF, GRC, and CSS and those with low or intermediate SYNTAX score. Conversely, in the group with the highest SYNTAX score, the risk of cardiac mortality was significantly higher in PCI patients (hazard ratio: 2.323, 95% confidence interval: 1.091 to 4.945, p = 0.029). In LM patients undergoing PCI, combined scores improve the discrimination accuracy of clinical or angiographic stand-alone tools. In LM patients undergoing CABG, the ACEF score has the best prognostic accuracy compared with other stand-alone or combined scores. The good predictive ability for PCI along with the poor predictive ability for CABG make the SYNTAX score the preferable decision-making tool in LM disease.