NPPB and myocardial infarction: A total of 23 preoperative potential confounding variables were included in the Lasso regression, and 8 potential risk factors for postoperative AKI were preliminarily screened: age, current smoker, hypertension, heart failure, previous myocardial infarction, cerebrovascular disease, CysC, and NT-proBNP (Figure 2).