The following clinical data were collected: (I) demographic characteristics: gender, age, primary disease, and blood transfusion; (II) comorbidity/comorbidities: hypertension, diabetes, hyperlipidemia, coronary heart disease (CHD), chronic heart failure, atrial fibrillation, a history of cerebral infarction, deep vein thrombosis (DVT), renal dysfunction, liver dysfunction, anemia, hypoproteinemia, and second surgery after primary operation; and (III) PCI occurrence and the time interval between surgery. We use propensity-score matching (PSM) at ratio 4:1 for the non-PCI cohort and the PCI cohort to balance the clinic characteristics between the 2 cohorts. A conditional logistic regression was used for the univariate analysis, and all the covariates were matched when the main risk factor was used for the univariate analysis.