Establishment of risk prediction model and risk score for in-hospital mortality after adult rheumatic heart valve surgery / 中华胸心血管外科杂志

ABSTRACT

Objective To establish a surgical risk prediction model for in-hospital mortality of adult rheumatic heart disease.Methods The study sample comprised of 3 889 patients with adult (is, or older than 18 years) rheumatic heart valve surgery only.All patients were divided into three subgroups according to the surgery site of left atrioventricular valve mitral valve surgery group;aortic valve surgery group;and mitral and aortic valve surgery group.The data was splited into development(60％) and validation(40％) data sets, and then the risk model was developed by using a logistic regression model according to the data in development data set.Model calibration was analyzed by Hosmer-Lemeshow goodness-of-fit statistic, and model discrimination was tested by calculating the area under the receiver operating characteristic(ROC) curve.Risk score was finally set up according to the coefficient β and rank of variables in logistic regression model.Results The general in-hospital mortality of the whole group is 4.2％ (165/3 889).We established a risk prediction model and found seven risk factors heart function in NYHA functional class ≥ Ⅱ grade (OR =3.36, 95％ CI 2.42-4.67) , preoperative creatinine ＞ 110 mmoL/L (OR =2.69, 95％ CI 1.51-4.79) , history of previous chest pain(OR =2.33, 95％ CI 1.07-5.11) , surgical status(OR =2.32, 95 ％ CI 0.94-5.73) , previous history of hypertension (OR =2.24, 95 ％ CI 1.19-4.23), preoperative critical state (OR =2.14, 95％ CI 1.27-3.60) and age ＞ 50 years (OR =1.57, 95 ％ CI 1.18-2.09).Our risk model showed good calibration and discriminative power for the development data set, validation data set, and three subgroup in which Hosmer-Leme-show test' s P value were greater than 0.05 and the area under the ROC curve were greater than 0.70.Scoring methods: age 51-60years 1 point, age 61-70 yeas 2 points, age ＞70 years 3 points;history of hypertension 1 point;creatinine ＞ 110 umol/L 4 points;NYHA class stage Ⅱ 2 points, NYHA class stage Ⅲ 4 points;NYHA class stage Ⅳ 6 points;history of previous chest pain 1point;preoperative critical condition 2 points;urgent surgery 2 points emergency surgery 4 points.Conclusion We have created a new risk prediction model and risk score, which can accurately predicts outcomes in patients undergoing heart valve surgery for our center.Furthermore, our risk model can also enable benchmarking and comparisons between multicenter in a meaningful way in the future.