1. National Heart and Lung Institute, Imperial College London, London, United Kingdom;
2. Respiratory Medicine and European Reference Network on Rare Multisystemic Vascular Diseases (VASCERN) HHT Centre, Imperial College Healthcare NHS Trust, London, United Kingdom;
3. Department of Haematology, Cambridge Biomedical Campus, University of Cambridge, Cambridge, United Kingdom;
4. National Institute for Health Research (NIHR) BioResource, Cambridge University Hospitals, Cambridge Biomedical Campus, Cambridge, United Kingdom;
5. Department of Surgery and Cancer, Imperial College London, London, United Kingdom;
6. Division of Medicine, University College London, London, United Kingdom;
7. Division of Pulmonary, Critical Care, Sleep, and Occupational Medicine, Indiana University School of Medicine, Indianapolis, IN;
8. Department of Biosciences and Nutrition, and Center for Innovative Medicine, Karolinska Institutet, Sweden; and
9. Medical Research Council Biostatistics Unit, Cambridge Biomedical Campus, University of Cambridge, Cambridge, United Kingdom