Pulmonary arterial hypertension (PAH) is a chronic disease associated with upregulation of hypoxia inducible-factor-1alpha (HIF-1alpha) and functional iron deficiency. The investigators are proposing a prospective, single-arm, open-label intervention to determine whether oral iron supplementation in patients with pulmonary arterial hypertension reduces markers of HIF activation and improve clinical parameters of disease. After the baseline visit, patients will be given ferrous sulfate tablets to take orally for 3 months. Outcome data will be collected at the baseline visit and at the end of the 3-month study period.
