Contiguous data were reported as median and range. Categorical data were expressed as percentage. Data were tested for normality using the D'agostino and Pearson's normality test. As not all data were normally distributed, nonparametric tests were chosen for the statistical analysis.
Changes of the ventricular parameters over time were tested with the Wilcoxon signed-rank test. All data of the group with significant RVEDVi progression (≥20 ml/m2) were compared with the same data of the group without significant RVEDVi progression (≤20 ml/m2). Continuous parameters were compared using the Mann–Whitney U-test. Categorical data were tested with the Chi-square test and the Fisher's exact test. The correlation between RV end-diastolic volume (RVEDV) changes over time and continuous parameters was assessed with the Spearman's rho correlation coefficient. These parameters included age at surgical repair, surgical technique used for repair, age at first CMR, time from surgical repair to first CMR, LV volumes and biventricular function at first CMR, and BSA changes.
The results were two tailed, and P < 0.05 was considered statistically significant. All statistical analyses were performed with SPSS Inc., Version 22.0 (Chicago, IL, USA) and Graphpad Prism Inc., Version 5 (San Diego, CA, USA) software.
The study was approved by the ethical authorities of both institutions.
Changes of the ventricular parameters over time were tested with the Wilcoxon signed-rank test. All data of the group with significant RVEDVi progression (≥20 ml/m2) were compared with the same data of the group without significant RVEDVi progression (≤20 ml/m2). Continuous parameters were compared using the Mann–Whitney U-test. Categorical data were tested with the Chi-square test and the Fisher's exact test. The correlation between RV end-diastolic volume (RVEDV) changes over time and continuous parameters was assessed with the Spearman's rho correlation coefficient. These parameters included age at surgical repair, surgical technique used for repair, age at first CMR, time from surgical repair to first CMR, LV volumes and biventricular function at first CMR, and BSA changes.
The results were two tailed, and P < 0.05 was considered statistically significant. All statistical analyses were performed with SPSS Inc., Version 22.0 (Chicago, IL, USA) and Graphpad Prism Inc., Version 5 (San Diego, CA, USA) software.
The study was approved by the ethical authorities of both institutions.