[1] Sheffield Pulm Vasc Dis Unit, Sheffield, S Yorkshire, England
[2] Royal Brompton Hosp, London, England
[3] Scottish Pulm Vasc Dis Unit, Glasgow, Lanark, Scotland
[4] Papworth Hosp NHS Fdn Trust, Cambridge, England
[5] Royal Free Hosp, London, England
[6] Imperial Coll Healthcare NHS Trust, London, England
[7] Univ Manchester, Manchester, Lancs, England