The variables finally included in the lasso logistic regression model included age, gender, hemoglobin, pulmonary hypertension, arrhythmia, hypertension, duration of CPB, the volume of autologous blood transfusion, pre-operative diagnosis, the highest level of lactate during the operation, albumin, BMI, vasoactive inotropic score and ejection fraction. This evidence concerns the gene ALB and pulmonary arterial hypertension.