Validation of the Coronary Artery Bypass Graft SYNTAX Score (Synergy Between Percutaneous Coronary Intervention With Taxus) as a Prognostic Marker for Patients With Previous Coronary Artery Bypass Graft Surgery After Percutaneous Coronary Intervention

Background— The efficacy and prognosis of percutaneous coronary intervention (PCI) as secondary revascularization in patients with previous coronary artery bypass graft surgery remain uncertain. Methods and Results— We retrospectively evaluated 434 consecutive patients with previous coronary artery bypass graft surgery hospitalized for PCI between 2004 and 2011 (men 84%, age 71 (interquartile range, 66–76) years) and calculated the coronary artery bypass graft Synergy Between Percutaneous Coronary Intervention With Taxus score (CSS) before (baseline CSS) and after PCI (post-PCI CSS). Patients were divided into 2 groups based on median post-PCI CSS: low-score (≤23; n=217) and high-score groups (>23; n=217). Major adverse cardiovascular events (MACE) were defined as the composite of cardiovascular death, myocardial infarction, and unplanned repeat revascularization for myocardial ischemia. The median baseline and post-PCI CSS were 30 (interquartile range, 21–40) and 23 (interquartile range, 14.5–33.5), respectively. During a median follow-up of 69 months, the prevalence of MACE and cardiac death differed significantly between the 2 post-PCI CSS groups (MACE: low, 13.8%; high, 28.6%; P <0.001; cardiac death: low, 6.2%; high, 16.7%; P =0.002). In multivariable analysis, the high post-PCI CSS divided by the median was associated with substantially greater cumulative MACE (hazard ratio, 2.09; 95% confidence interval, 1.31–3.34; P =0.002) and cardiac death (hazard ratio, 2.02; 95% confidence interval, 1.03–3.98; P =0.042) compared with the low post-PCI CSS. Net reclassification improvement analysis revealed that post-PCI CSS resulted in significantly improved prediction of MACE and cardiac death compared with baseline CSS. Conclusions— In this external validation study, the CSS was a potential prognostic factor after subsequent PCI, even for previous coronary artery bypass graft surgery patients.