Statistical Analysis
BITA and SITA groups were compared with the Fisher’s exact test for categorical variables, and the Mann-Whitney U test for continuous variables. Overall and MACE-free survival were estimated using the Kaplan-Meier method. Statistical differences were analyzed using the log-rank test. Univariate and multivariate analyses of the prognostic factors of overall survival were performed using the Cox proportional hazard models. Preoperative, operative, and postoperative variables were included in the univariate analysis. Age, sex, and variables with P value < 0.05 in the univariate analysis were included as variables in the multivariate analysis. P values < 0.05 were considered statistically significant. All statistical analyses were performed using EZR (Saitama Medical Center, Jichi Medical University, Saitama, Japan), which is a graphical user interface for R (version 3.3.3; The R foundation for Statistical Computing, Vienna, Austria)16.