NOTCH4 and pulmonary arterial hypertension: In preclinical and idiopathic PAH studies, p.KLF2‐induced exosomal miR‐181a‐5p and miR‐324‐5p are reduced in heritable PAH with the H288Y KLF2 mutation, leading to increased target gene expression and attenuated pulmonary vascular remodelling via Notch4, ETS1, and other vascular homeostasis regulators [71].