R 4.0.1 statistical package

The patients were divided into CHA₂DS₂-VASc score groups (≤2, =3, =4, =5, and ≥6) according to whether they had died by the end of follow-up. Baseline demographic and clinical characteristics were summarized using medians and interquartile ranges (IQRs) for continuous measures and percentages for categorical measures. The comparison of the data was performed using the chi-square test for categorical variables and Mann–Whitney U-test for continuous variables. Univariate and multivariate Cox regression models were used to explore the risk factors associated with mortality. According to the CHA₂DS₂-VASc score, Kaplan–Meier curves with the log-rank test were used to compare survival. The calibration of the CHA₂DS₂-VASc score was assessed with the Hosmer-Lemeshow goodness-of-fit test (HL), which may determine the degree of agreement between the observed event rate and the predicted one over a series of scores. A significant value of P < 0.05 represents a lack of fit. The concordance index (C-index) was conducted to determine the discrimination of and the diagnostic value of the CHA₂DS₂-VASc score for death. All analysis were performed with the R 4.0.1 Statistical Package (the R foundation for Statistical Computing, Vienna, Austria) and SPSS v.24.0 (Statistical Package for Social Science; IBM, Chicago, IL, USA).

The continuous variables are presented as means ± SD and compared between control and CA patient groups using the Mann–Whitney U test. Receiver operating characteristic (ROC) curves were used to determine the diagnostic TBRmax and native T1 values for CA. Spearman's correlation analysis was performed to determine the degree of association (Spearman's r value) between native T1 value and TBRmax. P < 0.05 was considered statistically significant. All statistical analyses were performed using the R 4.0.1 Statistical Package (the R foundation for Statistical Computing, Vienna, Austria) and SPSS software v.24.0 (Statistical Package for Social Science; IBM, Chicago, IL, USA).