Figure 3.

Several lipids have differential trans-RV (PA vs SVC) and transpulmonary (AAO vs PA) gradients in paediatric PAH (vs non-PAH control). Volcano plots (A and B) show pairs of lipids with statistically significant fold change differences. Interestingly, all such lipids had a step-up in PAH and a step-down in controls trans-RV (A), while the fold change direction was reversed (PAH down, non-PAH controls up) for the lipids with significantly different gradients transpulmonary (B). Statistical test: Wald χ² test (linear mixed effects models). Data filtration: see legend for figure 1. AAO, ascending aorta; CE, cholesterol ester; DAG, diacylglycerol; FA, fatty acid; FFA, free FA; FDR, false discovery rate; FC, fold change; PAH, pulmonary arterial hypertension; PC, phosphatidylcholine; RV, right ventricle; SVC, superior vena cava; TAG, triacylglycerol; Trans-PC, transpulmonary circulation.