IL1B and pulmonary arterial hypertension: IL‐1β also accumulates in the right ventricle of patients with PAH (Cracowski et al., 2014; Duncan et al., 2012; Elaine et al., 2010; Humbert et al., 1995; McMahan, Schoenhoff, Van Eyk, Wigley, & Hummers, 2015).