Page 99 - Assessing right ventricular function and the pulmonary circulation in pulmonary hypertension Onno Anthonius Spruijt

Treatment response
Treatment responses were assessed by the baseline-to-follow-up responses in hemodynamics, cardiac function and 6MWD. Time between baseline and follow-up was 1.9 ± 1.6 years in the DLCO<43% group, 1.6 ± 1.2 years in the DLCO 43-62% group and 2.1 ± 2.2 years in the DLCO>62% group (p=0.860).
Statistical analysis
Data are presented as mean ± standard deviation (SD) unless stated otherwise. Comparisons of baseline hemodynamics, cardiac function and the change in hemodynamic and cardiac function after PAH-specific therapies between the DLCO<43%, DLCO 43-62% and the DLCO>62% group were performed using one-way ANOVA with Bonferroni post-hoc corrections and Kruskas-Wallis tests with Dunn’s multiple comparisons post-hoc test as appropriate. Kaplan-Meier analyses were performed to test for survival differences between the DLCO<43%, DLCO 43-62% and the DLCO>62% groups in the entire cohort and the cohort in which a MRI at follow-up was present. Kaplan-meier analysis was also performed to test for survival differences between the subjects with and without a CMRI at follow-up in the DLCO<43% group. Subsequently, multivariable cox regression analyses were performed to correct the association between DLCO and survival for age differences. Statistical analyses were performed using SPSS for Windows version 20 (IBM Corp., Armonk, NY, USA) and GraphPad Prism for Windows version 6 (GraphPad Software, Inc., San Diego, CA, USA). P-values <0.05 were considered statistically significant.
Results
Characteristics of the DLCO<43%, DLCO 43-62% and DLCO>62% patients are summarized in table 1. A detailed characterization of the majority of patients was already given in our previous study [5].
Baseline measurements
SvO2, LVEDVI and LVESVI were significantly lower in the DLCO<42% group compared to the DLCO>62% group. Except from these, baseline hemodynamics and cardiac function were not different between groups. Exercise capacity, assessed by the 6MWT, was significantly lower in the DLCO<42% group compared to the moderately reduced and preserved DLCO group, as well as the arterial oxygen tension and saturation at rest. Furthermore, the DLCO<42% group showed a larger drop in arterial oxygen saturation during exercise (Table 1).
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