European Respiratory Journal | 2019
Thoracic CT features of patients with BMPR2 mutation: preliminary analysis from the UK National Cohort Study of Idiopathic and Heritable PAH
Abstract
Introduction: Mutations in the bone morphogenetic receptor type 2 (BMPR2) gene are the commonest genetic cause of heritable pulmonary arterial hypertension (PAH). The aim of this study was to investigate thoracic computed tomography (CT) features in patients with idiopathic and heritable PAH and BMPR2 mutations. Methods: Patients with idiopathic or heritable PAH were selected; patients with mutations other than BMPR2 were excluded. CT features were assessed with observers blinded to the BMPR2 status. Independent t-test, Chi2 test, binary logistic regression and one-way ANCOVA were used to compare patients with and without BMPR2 mutation. Results: In a preliminary analysis of 111 patients with IPAH or HPAH from the Sheffield Pulmonary Vascular Disease Unit, 19 had a BMPR2 mutation. Mutation carriers were younger (p=0.009). No sex difference was identified (p=0.313). New peripheral lung blood vessels ‘neovascularity’ and enlarged bronchial arteries were observed in BMPR2 mutation carriers (p 0.05). After adjusting for age, sex, body surface area, WHO functional class, mPAP and PVR, a smaller left atrial area and smaller main pulmonary artery diameter were associated with a BMPR2 mutation. Conclusion: In this preliminary analysis of the UK National IPAH cohort, we have observed that BMPR2 carriers had smaller pulmonary arteries and smaller left atria. Whether this reflects differences in RV afterload and left ventricle preload requires further investigation.