Fig. 4

Principle component analysis of inflammatory markers in plasma of PAH and CTEPH patients. a–d Unsupervised principle component analysis (PCA) of inflammatory markers, measured by ELISA, in plasma of healthy controls (HC) and the indicated WHO PH patient subgroups at diagnosis (a, b) and at 1-year follow-up (c, d). PCAs were on log10-transformed and scaled concentrations values; each symbol point represents an individual patient or HC sample (a, c). Representation of the contribution in percentages of the variables on the first (Dim.1) and second (Dim.2) principal component at diagnosis (b) and at 1-year follow-up (d). The blue color range indicates the contribution to the principal components. e PCA plot of average coordinates of Dim1 and Dim2 for the indicated WHO PH patient subgroups. Arrows between the dots represent the PC change from diagnosis to 1-year follow up. Statistical analysis was performed by a one-way ANOVA (Kruskal–Wallis test) combined with a Dunn’s multiple comparison test. * = p < 0.05, ** = p < 0.01