Vascular involvement in idiopathic pulmonary fibrosis

Abstract

BackgroundIdiopathic pulmonary fibrosis (IPF) is a chronic, fibrosing and progressive interstitial lung disease of unknown aetiology with a pathogenesis still partly unknown. Several microvascular and macrovascular abnormalities have been demonstrated in the pathogenesis of IPF and related pulmonary hypertension (PH), a complication of the disease.MethodsWe carried out a non-systematic, narrative literature review aimed at describing the role of vasculature in the natural history of IPF.ResultsThe main molecular pathogenetic mechanisms involving vasculature (i.e.endothelial to mesenchymal transition, vascular remodelling, endothelial permeability, occult alveolar haemorrhage, vasoconstriction and hypoxia) and the genetic basis of vascular remodelling are described. The prevalence and clinical relevance of associated pulmonary hypertension are highlighted with focus on the vasculature as a prognostic marker. The vascular effects of current antifibrotic therapies, the role of pulmonary vasodilators in the treatment of disease, and the new pharmacological options with vascular-targeted activity are described.ConclusionsThe vasculature plays a key role in the natural history of IPF from early phases of disease until development of PH in a subgroup of patients, a complication related to a worse prognosis. Pulmonary vascular volume has emerged as a novel computed tomography finding and a predictor of mortality, independent of PH. New pharmacological options with a concomitant vascular-directed activity might be promising in the treatment of IPF.