Exhaled Breath Olfactory Signature of Pulmonary Arterial Hypertension

Pulmonary arterial hypertension (PAH) is a progressive and rare severe disease (prevalence of 15-50 per million) due to obstruction of small pulmonary arteries, leading to an increase in pulmonary artery pressure with the ultimate consequence right heart failure. Despite recent advances in therapeutic care, there is no cure and most patients die or require lung transplantation within 5 years of diagnosis. Currently, right heart catheterisation is required to diagnose PAH and monitor response to treatment. Right heart catheterisation is an invasive test, and alternatives such as echocardiography have not yielded sufficient accuracy both for early diagnosis and disease monitoring. Currently, PAH is often diagnosed at an advanced stage of the disease. There is often a delay in diagnosis of several years between the first symptoms and the identification of the disease due to the non-specific nature of symptoms. Hence, there is the need to improve the time between the first signs and definitive diagnosis of the disease. Early diagnosis of PAH remains a challenge due to the low sensitivity and specificity of biomarkers available currently. The main objective is to validate the results obtained in the previous preliminary proof of concept study - that PAH patients display a unique olfactory signature that can be detected by an artificial E- nose. Secondary objectives are to investigate the ability of the E-nose to: * Discriminate patients with idiopathic PAH from those with heritable PAH due to BMPR2 mutations * Discriminate patients with chronic thromboembolic pulmonary hypertension (CTEPH) from healthy controls, and patients with idiopathic and/or heritable PAH. * Detect development of PAH in BMPR2 mutation carriers * Determine whether the olfactory signature can stratify subgroups of patients by correlating the olfactory signature to different biological and clinical parameters (hemodynamic measurements, NYHA class, duration of treatment, 6-minute walk distance, response to nitric oxide, BNP levels).