French PH Network PULMOTENSION Investigators: Claire Dauphin (Service de Cardiologie et Maladies Vasculaires, Hôpital Gabriel Montpied, CHU de Clermont-Ferrand, Clermont-Ferrand, France), Marie Fertin (CHU Lille, Service de Cardiologie, Lille, France), Laurianne Le Gloan (Department of Paediatric Cardiology and Paediatric Cardiac Surgery, Children's Hospital, CHU Nantes, Nantes, France), Pascal Magro (Service de Pneumologie, CHU de Tours, Tours, France), Pierre Mauran (Services of Paediatric and Congenital Cardiology, CHU de Reims, Reims, France), and Elise Noel-Savina and Grégoire Prévot (both from Service de Pneumologie, Hôpital Larrey, Toulouse, France).

Author contributions: J. Grynblat, C. Khouri, M.C. Chaumais, M. Humbert and D. Montani designed the initial concept. J. Grynblat and C. Khouri performed the statistical analysis. J. Grynblat and D. Montani wrote the manuscript. J. Grynblat, C. Khouri, M.C. Chaumais, A. Hlavaty, F. Perros, L. Savale, M. Humbert, D. Montani and French PH Network PULMOTENSION Investigators (L. Le Gloan, C. Dauphin, M. Fertin, P. Magro, P. Mauran, E. Noel-Savina and G. Prévot) participated in acquisition and interpretation of data. All the authors reviewed the manuscript.

Conflict of interest: X. Jaïs reports grants from Acceleron, Janssen, MSD and Bayer HealthCare, lecture honoraria from Janssen and MSD, and travel support from MSD, outside the submitted work. L. Savale reports grants from Acceleron, AOP Orphan, Janssen, Merck and Shou Ti, consulting fees from Acceleron, Bayer, Janssen and Merck, and lecture honoraria from Janssen and Merck, outside the submitted work. M. Jevnikar reports consulting fees from Janssen, and travel support from MSD and Janssen, outside the submitted work. A. Boucly reports grants from Acceleron, Janssen and MSD, and lecture honoraria and travel support from Janssen, Merck, AOP Orphan and Ferrer, outside the submitted work. G. Simonneau reports consulting fees and lecture honoraria from Actelion, Jansen, Bayer and MSD, travel support from Janssen, and advisory board participation with Acceleron, outside the submitted work. O. Sitbon reports grants from Acceleron (now MSD), AOP Orphan, Janssen (formerly Actelion) and MSD, consulting fees from Acceleron (now MSD), Altavant (now Enzyvant), AOP Orphan, Ferrer, Gossamer Bio, Janssen (formerly Actelion) and MSD, lecture honoraria from AOP Orphan, Janssen (formerly Actelion), Ferrer and MSD, and advisory board participation with Altavant (now Enzyvant), Gossamer Bio, Janssen (formerly Actelion) and MSD, outside the submitted work. M. Humbert reports grants from Acceleron, AOP Orphan, Janssen, Merck and Shou Ti, consulting fees from Acceleron, Aerovate, Altavant, AOP Orphan, Bayer, Chiesi, Ferrer, Janssen, Merck, Morphogen-IX, Shou Ti and United Therapeutics, lecture honoraria from Janssen and Merck, and advisory board participation with Acceleron, Altavant, Janssen, Merck and United Therapeutics, outside the submitted work. D. Montani reports grants from Acceleron, Janssen and Merck MSD, consulting fees from Acceleron, Merck MSD, Janssen and Ferrer, and lecture honoraria from Bayer, Janssen, Boehringer, Chiesi, GSK, Ferrer and Merck MSD, outside the submitted work. The remaining authors have no potential conflicts of interest to disclose.