title: The pathophysiology of chronic thromboembolic pulmonary hypertension.
abstract: Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare, progressive pulmonary vascular disease that is usually a consequence of prior acute pulmonary embolism. CTEPH usually begins with persistent obstruction of large and/or middle-sized pulmonary arteries by organised thrombi. Failure of thrombi to resolve may be related to abnormal fibrinolysis or underlying haematological or autoimmune disorders. It is now known that small-vessel abnormalities also contribute to haemodynamic compromise, functional impairment and disease progression in CTEPH. Small-vessel disease can occur in obstructed areas, possibly triggered by unresolved thrombotic material, and downstream from occlusions, possibly because of excessive collateral blood supply from high-pressure bronchial and systemic arteries. The molecular processes underlying small-vessel disease are not completely understood and further research is needed in this area. The degree of small-vessel disease has a substantial impact on the severity of CTEPH and postsurgical outcomes. Interventional and medical treatment of CTEPH should aim to restore normal flow distribution within the pulmonary vasculature, unload the right ventricle and prevent or treat small-vessel disease. It requires early, reliable identification of patients with CTEPH and use of optimal treatment modalities in expert centres.
authors.affiliation: Assistance Publique-Hôpitaux de Paris, Service de Pneumologie, Hôpital Bicêtre, Le Kremlin-Bicêtre, Hôpital Marie Lannelongue, Paris Sud University, Paris, France gerald.simonneau@gmail.com.
authors.forename: Gérald
authors.initials: G
authors.lastname: Simonneau
authors.affiliation: Dept of Pulmonary Circulation and Thromboembolic Diseases, Centre of Postgraduate Medical Education, Europejskie Centrum Zdrowia Otwock, Otwock, Poland.
authors.forename: Adam
authors.initials: A
authors.lastname: Torbicki
authors.affiliation: Dept of Pathology, Paris Sud University, Hôpital Marie Lannelongue, Le Plessis-Robinson, France.
authors.forename: Peter
authors.initials: P
authors.lastname: Dorfmüller
authors.affiliation: Division of Pulmonary and Critical Care Medicine, University of California San Diego, La Jolla, CA, USA.
authors.forename: Nick
authors.initials: N
authors.lastname: Kim
mesh_terms: D000328:Adult; D000818:Animals; D005260:Female; D006439:Hemodynamics; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology* / Q000628:therapy; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D011237:Predictive Value of Tests; D011379:Prognosis; D011651:Pulmonary Artery / Q000503:physiopathology*; D011652:Pulmonary Circulation; D011655:Pulmonary Embolism / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D018570:Risk Assessment; D012307:Risk Factors; D055815:Young Adult