The Chinese coronary artery bypass grafting registry study: how well does the EuroSCORE predict operative risk for Chinese population?

OBJECTIVE The European System for Cardiac Operative Risk Evaluation (EuroSCORE) model is a widely used risk prediction algorithm for cardiac surgery in China due to lack of a local model, although its validation has never been tested. The aim of this study was to assess the performance of the logistic EuroSCORE when applied in the Chinese Coronary Artery Bypass Grafting Registry database, which is representative of adult cardiac surgery in China. METHODS The logistic EuroSCORE model was applied to all patients undergoing coronary artery bypass grafting (CABG) surgery at 35 centres in China between January 2004 and December 2005. The entire cohort and a subgroup of patients undergoing isolated CABG were analysed. The calibration of the EuroSCORE model was assessed by comparing observed and predicted in-hospital mortalities. Discrimination was tested by determining the area under the receiver operating characteristic (ROC) curve. RESULTS The Chinese CABG Registry Study recruited 9248 patients. There were significant differences in the prevalence of risk factors between the Chinese population and European cardiac surgical populations. For the entire cohort, the predicted mortality was 5.51% and observed mortality was 3.27%. Of the isolated CABG subset of 8120 patients, the predicted mortality was 4.21% and the observed mortality was 2.22%. The logistic EuroSCORE overpredicted observed mortality for the entire cohort and the isolated CABG subset at all risk tertiles to different degrees. The discriminative power of EuroSCORE was acceptable but not very satisfactory, with an area under the ROC curve of 0.72 for the entire cohort and 0.71 for the isolated CABG subset. CONCLUSION EuroSCORE model does not accurately predict outcomes in this group of Chinese CABG patients. Therefore, caution should be exercised when using it for risk prediction in China. Creation of a new model, which accurately predicts outcomes in Chinese CABG patients, is warranted.