Yuan Xin, Zheng Zhe, Li Yan, Hu Shengshou
Department of Cardiovascular Surgery, Center for Cardiovascular Regenerative Medicine, Fuwai Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.
Heart Surg Forum. 2008 Dec;11(6):E346-51. doi: 10.1532/HSF98.20081113.
This research was aimed at validating a new risk model for in-hospital mortality in Chinese patients undergoing coronary artery bypass graft (CABG) surgery. This model (NYS), which was developed for isolated CABG surgery from data of New York's cardiac surgery reporting system in 2002, was proved effective, but its validation in Chinese patients has yet to be carried out.
The original model was recalibrated, and the fitness of the recalibrated model was tested in the Chinese Coronary Artery Bypass Graft Registry. From January 2004 to December 2005, 9248 patients undergoing CABG were enrolled in the Chinese CABG Registry, and 8120 patients who underwent isolated CABG were selected for the current study.
The C statistic value for the original model was 0.74 (95% confidence interval [CI], 0.70-0.78), and the chi2 statistic was >26.13 (P < .001), indicating a necessity for recalibration. The fit of the recalibrated model was satisfactory (C statistic, 0.74 [95% CI, 0.70-0.78]; chi2 = 5.98; P = .65). Furthermore, translation of risk profiles into NYS scores revealed strong correlations between risk-score levels and different end points, including in-hospital mortality, major adverse cardiac events, and length of intensive care unit stay. Independent predictors were identified in the Chinese CABG Registry. Many predictors for the Chinese CABG Registry were the same as those in the NYS model.
The original NYS system overestimates in-hospital mortalities in Chinese patients undergoing CABG, whereas the recalibrated model corrects such overestimations. This model can be a useful risk-predictive tool for Chinese patients undergoing isolated CABG.
本研究旨在验证一种针对接受冠状动脉旁路移植术（CABG）的中国患者院内死亡的新风险模型。该模型（NYS）于2002年根据纽约心脏手术报告系统的数据开发，用于单纯CABG手术，已被证明有效，但尚未在中国患者中进行验证。
对原始模型进行重新校准，并在中国冠状动脉旁路移植术登记处测试重新校准模型的拟合度。2004年1月至2005年12月，9248例接受CABG的患者被纳入中国CABG登记处，其中8120例接受单纯CABG的患者被选入本研究。
原始模型的C统计值为0.74（95%置信区间[CI]，0.70 - 0.78），卡方统计量>26.13（P <.001），表明有重新校准的必要。重新校准模型的拟合度令人满意（C统计量，0.74[95%CI，0.70 - 0.78]；卡方 = 5.98；P =.65）。此外，将风险概况转换为NYS评分显示，风险评分水平与不同终点之间存在强相关性，包括院内死亡、主要不良心脏事件和重症监护病房住院时间。在中国CABG登记处确定了独立预测因素。中国CABG登记处的许多预测因素与NYS模型中的相同。
原始NYS系统高估了接受CABG的中国患者的院内死亡率，而重新校准的模型纠正了这种高估。该模型可为接受单纯CABG的中国患者提供有用的风险预测工具。
