BMPR2 and pulmonary arterial hypertension: A meta-analysis of 1,550 PAH patients [19] found that those with BMPR2 mutations were younger and had a more severe form of PAH, associated with high mortality and poor prognosis, than those with normal BMPR2. BMPR2 haplo-insufficiency is associated with increased endothelial apoptosis, transformational EC metabolism, and PASMC proliferation, which facilitate the development of pulmonary hypertension.