title: Pre-Capillary, Combined, and Post-Capillary Pulmonary Hypertension: A Pathophysiological Continuum.
abstract: Pulmonary hypertension (PH) is hemodynamically classified as pre-capillary (as seen in idiopathic pulmonary arterial hypertension [IPAH]) or post-capillary (as seen in heart failure with preserved ejection fraction [HFpEF]). Overlaps between these conditions exist. Some patients present with risk factors for left heart disease but pre-capillary PH, whereas patients with HFpEF may have combined pre- and post-capillary PH.
  
  
  
  This study sought to further characterize similarities and differences among patient populations with either PH-HFpEF or IPAH.
  
  
  
  We used registry data to analyze clinical characteristics, hemodynamics, and treatment responses in patients with typical IPAH (<3 risk factors for left heart disease; n = 421), atypical IPAH (≥3 risk factors for left heart disease; n = 139), and PH-HFpEF (n = 226) receiving PH-targeted therapy.
  
  
  
  Compared with typical IPAH, patients with atypical IPAH and PH-HFpEF were older, had a higher body mass index, had more comorbidities, and had a lower 6-min walking distance, whereas mean pulmonary artery pressure (46.9 ± 13.3 mm Hg vs. 43.9 ± 10.7 mm Hg vs. 45.7 ± 9.4 mm Hg, respectively) and cardiac index (2.3 ± 0.8 l/min/m(2) vs. 2.2 ± 0.8 l/min/m(2) vs. 2.2 ± 0.7 l/min/m(2), respectively) were comparable among groups. After initiation of targeted PH therapies, all groups showed improvement in exercise capacity, functional class, and natriuretic peptides from baseline to 12 months, but treatment effects were less pronounced in patients with PH-HFpEF than typical IPAH; with atypical IPAH in between. Survival rates at 1, 3, and 5 years were almost identical for the 3 groups.
  
  
  
  Patients with atypical IPAH share features of both typical IPAH and PH-HFpEF, suggesting that there may be a continuum between these conditions.
authors.affiliation: Department of Cardiology, DRK Kliniken Berlin, Berlin, Germany; Department of Cardiology, Medical University of Greifswald, Greifswald, Germany. Electronic address: c.opitz@drk-kliniken-berlin.de.
authors.forename: Christian F
authors.initials: CF
authors.lastname: Opitz
authors.affiliation: Department of Respiratory Medicine and German Center of Lung Research (DZL), Hannover Medical School, Hannover, Germany.
authors.forename: Marius M
authors.initials: MM
authors.lastname: Hoeper
authors.affiliation: Department of Cardiology, National Heart & Lung Institute, Imperial College London, London, United Kingdom.
authors.forename: J Simon R
authors.initials: JS
authors.lastname: Gibbs
authors.affiliation: Department of Pediatric Cardiology and Congenital Heart Disease, German Heart Center, München, Technical University Munich, Munich, Germany.
authors.forename: Harald
authors.initials: H
authors.lastname: Kaemmerer
authors.affiliation: Pulmonary Vascular Diseases Unit, Papworth Hospital, Cambridge, United Kingdom.
authors.forename: Joanna
authors.initials: J
authors.lastname: Pepke-Zaba
authors.affiliation: Cardiology Department, Royal Free Hospital, London, United Kingdom.
authors.forename: J Gerry
authors.initials: JG
authors.lastname: Coghlan
authors.affiliation: Division of Cardiology, Fondazione IRCCS Policlinico S. Matteo, Pavia, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Scelsi
authors.affiliation: Department of Cardiology, Second University of Naples-Monaldi Hospital, Naples, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: D'Alto
authors.affiliation: Department of Respiratory Medicine and German Center of Lung Research (DZL), Hannover Medical School, Hannover, Germany.
authors.forename: Karen M
authors.initials: KM
authors.lastname: Olsson
authors.affiliation: Clinic of Pulmonology, University Hospital Zurich, Zurich, Switzerland.
authors.forename: Silvia
authors.initials: S
authors.lastname: Ulrich
authors.affiliation: Department of Cardiology, Heart and Diabetes Center North Rhine-Westphalia, Ruhr University Bochum, Bad Oeynhausen, Germany.
authors.forename: Werner
authors.initials: W
authors.lastname: Scholtz
authors.affiliation: Clinic for Thoracic and Cardiovascular Surgery, Heart and Diabetes Center NRW, Ruhr University Bochum, Bad Oeynhausen, Germany.
authors.forename: Uwe
authors.initials: U
authors.lastname: Schulz
authors.affiliation: Centre for Pulmonary Hypertension, University Hospital, Heidelberg, Germany.
authors.forename: Ekkehard
authors.initials: E
authors.lastname: Grünig
authors.affiliation: Pulmonary Hypertension Unit Department of Cardiovascular and Respiratory Disease, University of Rome 'La Sapienza,' Rome, Italy.
authors.forename: Carmine D
authors.initials: CD
authors.lastname: Vizza
authors.affiliation: Medical Clinic I, Pneumology, Loewenstein Clinic, Loewenstein, Germany.
authors.forename: Gerd
authors.initials: G
authors.lastname: Staehler
authors.affiliation: Department of Internal Medicine, Unfallkrankenhaus Berlin, Berlin, Germany.
authors.forename: Leonhard
authors.initials: L
authors.lastname: Bruch
authors.affiliation: Epidemiology Unit, German Rheumatism Research Centre, Berlin; Department of Rheumatology and Clinical Immunology, Charité University Hospital, Berlin, Germany.
authors.forename: Doerte
authors.initials: D
authors.lastname: Huscher
authors.affiliation: Institute for Clinical Pharmacology, Medical Faculty, Technical University Carl Gustav Carus, Dresden, Germany.
authors.forename: David
authors.initials: D
authors.lastname: Pittrow
authors.affiliation: Clinic III for Internal Medicine (Cardiology), and Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany; Cologne Cardiovascular Research Center (CCRC), University of Cologne, Cologne, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Rosenkranz
mesh_terms: D000368:Aged; D006328:Cardiac Catheterization; D005060:Europe / Q000453:epidemiology; D015444:Exercise / Q000502:physiology; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D006801:Humans; D006976:Hypertension, Pulmonary / Q000209:etiology / Q000401:mortality / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013318:Stroke Volume / Q000502:physiology*; D015996:Survival Rate / Q000639:trends; D000070857:Walk Test
keywords: heart failure with preserved ejection fraction; idiopathic pulmonary arterial hypertension