Integrating the residual SYNTAX score to improve the predictive ability of the age, creatinine, and ejection fraction (ACEF) score for cardiac mortality in percutaneous coronary intervention patients.

Abstract

To improve the prognostic value of the age, creatinine, and ejection fraction (ACEF) score following percutaneous coronary intervention (PCI) by integrating the residual SYNTAX score (rSS). ACEF score was proposed for predicting the operative mortality risk in elective cardiac operations and has been validated in numerous studies. However, it does not incorporate coronary lesion-based variables for risk assessment of patients who undergo PCI. Overall, 10,072 patients who underwent PCI at our hospital in 2013 were enrolled. The endpoint was 2-year cardiac death after PCI, defined as death that was not attributed to a non-cardiac cause. ACEF-rSS was constructed with incremental weights attributed to the ACEF score and rSS according to their estimated coefficients. 2-year cardiac death occurred in 63 patients (0.63%). In multivariable analyses, the ACEF score and rSS > 8 were independently associated with the risk of cardiac death. ACEF-rSS was computed as age (years)/ejection fraction (%) + 1 (if creatinine ≥2.0 mg/dl) + 1 (if rSS >8). The discrimination of ACEF-rSS was significantly better than that of the ACEF score based on receiver operating characteristic (ROC) curve analysis and integrated discrimination improvement (IDI) (C-statistics = 0.835 vs. 0.776 for ACEF-rSS and ACEF score, respectively, p = .029; IDI = 0.014, p < .001). Compared with all other SYNTAX-derived risk scores, ACEF-rSS had significantly better discrimination ability based on ROC curve analysis, net reclassification improvement, and IDI. Combining the ACEF score with rSS to produce the ACEF-rSS enhanced the predictive ability for long-term cardiac mortality.