Angiogenesis has also been shown to influence PHT, with studies demonstrating that the maintenance of increased portal pressure, hyperkinetic circulation, splanchnic neovascularization, and portosystemic collateralization is regulated by vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF) [13]. This evidence concerns the gene VEGFA and pulmonary hypertension, primary, 1.