Statistical analysis
Patients were divided according to the severity of TR into two groups,
those with no or mild TR and those with moderate to severe TR.
All data were summarized and displayed as mean ± standard deviation for
continuous variables unless stated otherwise, and as number (percentage)
of patients in each group for categorical variables. The p values
for the categorical variables were calculated with the chi-square test.
Continuous variables were compared using the independent sample t-test
or the Mann-Whitney U test. The Kaplan-Meier method and log-rank test
were used to evaluate
the association between the severity of TR and survival. To assess if TR
grade was
independently associated with outcome, we used multivariate Cox
Regression for the primary endpoint (all-cause mortality) adjusted for
all baseline variables found to be significant in the univariate
analysis. A two-tailed p-value of < 0.05 was considered
significant for all analyses. All analyses were performed with the SPSS
software (SPSS Inc., Chicago, IL).