[Chinese risk stratification scoring system for coronary artery bypass grafting].

OBJECTIVE

To construct a scoring system for the prediction of in-hospital mortality in Chinese patients undergoing coronary artery bypass grafting (CABG).

METHODS

From 2007 to 2008, complete clinical information of 9564 consecutive CABG patients was collected from Chinese coronary artery bypass grafting registry which recruited patients from 43 Chinese centers. This database was randomly divided into developmental and validation subsets (9:1). A risk model was developed using logistic regression. Calibration and discrimination characteristics were assessed in the validation dataset. Thresholds were defined for each model to distinguish different risk groups. The risk model was compared with EuroSCORE system in the validation dataset.

RESULTS

In the developmental dataset, calibration by Hosmer-Lemeshow (HL) test was P = 0.44 and discrimination by area under ROC (AUC) was 0.80. In the validation dataset, HL test was P = 0.34, AUC was 0.78. The performance turned out good for all three risk groups. Superiority were found over EuroSCORE (HL P = 0.60; AUC 0.73). The scoring system identified 11 risk factors (with weights in brackets): age over 65 (65 - 69, 3; 70 - 74, 5; over 75, 6), preoperative NYHA stage (NHYA III, 3; NHYA IV, 7), chronic renal failure (6), extracardiac arteriopathy (5), chronic obstructive pulmonary disease (4), Preoperative atrial fibrillation or flutter (within two weeks) (2), left ventricular ejection fraction < 50% (4), other than elective surgery (5), combined valve procedure (4), preoperative critical state (4), BMI (> 24 kg/m(2), -2; < 18 kg/m(2), 5).

CONCLUSION

This study constructs a simple, objective and accurate risk stratification system for Chinese patients undergoing CABG using the most up-to-date data.