Patient characteristics for Dublin (n = 43) and Sheffield cohorts (n = 52) at time of diagnostic catheter study.

Data presented as median (quartiles). Walk distance was measured by the 6-minute walk test (6MWT) in Dublin and the incremental shuttle walk test (ISWT) in Sheffield. One patient from Dublin was subsequently lost to follow-up (CTD patient, WHO-FC 1).Definition of abbreviations: IPAH = Idiopathic pulmonary arterial hypertension, CTD = Connective tissue disease, mPAP = Mean Pulmonary Artery Pressure, mRAP = Mean Right Atrial Pressure, PCWP = Pulmonary Capillary Wedge Pressure, PVR = pulmonary vascular resistance, WHO FC = World health organization functional class, ERA = Endothelin receptor antagonist, PDE5 = Phosphodiesterase-5 inhibitor.Patient characteristics for Dublin (n = 43) and Sheffield cohorts (n = 52) at time of diagnostic catheter study.