Statistical analysis
Continuous variables are reported as median (interquartile range
[IQR]), and categorical variables are reported as number
(percentage). The temporal trend in operative mortality over the study
period was visualized with a Loess smoothing estimator and was formally
tested with a Wilcoxon rank sum test. Long-term mortality was depicted
graphically using the Kaplan-Meier estimator, and the reverse
Kaplan-Meier method was used to summarize follow-up time. The unadjusted
association between select baseline factors and mortality was assessed
in univariable Cox proportional hazards models. Because few of the
patients (3 patients) underwent completion pericardiectomy, this group
was combined with the radical pericardiectomy group. These analyses were
done in SAS version 9.4 (SAS Institute, Cary NC).