title: Exercise physiological responses to drug treatments in chronic thromboembolic pulmonary hypertension.
abstract: We tested the hypothesis that patients with chronic thromboembolic pulmonary hypertension (CTEPH) that was deemed to be inoperable were more likely to respond to drugs for treating pulmonary arterial hypertension (PAH) by using cardiopulmonary exercise (CPX) testing than those with CTEPH that was deemed to be operable. We analyzed CPX testing data of all patients with CTEPH who were treated with PAH drugs and had undergone CPX testing before and after treatment at a single pulmonary hypertension center between February 2009 and March 2013. Suitability for pulmonary endarterectomy (PEA) was decided by experts in PEA who were associated with a treatment center. The group with inoperable CTEPH included 16 patients, the operable group included 26 patients. There were no differences in demographics and baseline hemodynamic data between the groups. Unlike patients in the operable group, after drug treatment patients with inoperable CTEPH had a significantly higher peak V̇o2 (P < 0.001), work load (P = 0.002), and oxygen pulse (P < 0.001). In terms of gas exchange, there was an overall net trend toward improved V̇e/V̇co2 in the group with inoperable CTEPH, with an increased PaCO2 (P = 0.01), suggesting reduced hyperventilation. No changes were observed in patients with operable CTEPH. In conclusion, treatment with PAH drug therapy reveals important pathophysiological differences between inoperable and operable CTEPH, with significant pulmonary vascular and cardiac responses in inoperable disease. Drug effects on exercise function observed in inoperable CTEPH cannot be translated to all forms of CTEPH.
authors.affiliation: National Pulmonary Hypertension Service, Imperial College Healthcare NHS Trust, Hammersmith Hospital, London, United Kingdom;
authors.forename: Athanasios
authors.initials: A
authors.lastname: Charalampopoulos
authors.affiliation: National Pulmonary Hypertension Service, Imperial College Healthcare NHS Trust, Hammersmith Hospital, London, United Kingdom; National Heart & Lung Institute, Imperial College London, London, United Kingdom;
authors.forename: J Simon R
authors.initials: JS
authors.lastname: Gibbs
authors.affiliation: National Pulmonary Hypertension Service, Imperial College Healthcare NHS Trust, Hammersmith Hospital, London, United Kingdom;
authors.forename: Rachel J
authors.initials: RJ
authors.lastname: Davies
authors.affiliation: National Pulmonary Hypertension Service, Imperial College Healthcare NHS Trust, Hammersmith Hospital, London, United Kingdom;
authors.forename: Wendy
authors.initials: W
authors.lastname: Gin-Sing
authors.affiliation: Department of Respiratory Medicine, Imperial College Healthcare NHS Trust, Hammersmith Hospital, London, United Kingdom;
authors.forename: Kevin
authors.initials: K
authors.lastname: Murphy
authors.affiliation: Pulmonary Vascular Diseases Unit, Papworth Hospital, Cambridge, United Kingdom; and.
authors.forename: Karen K
authors.initials: KK
authors.lastname: Sheares
authors.affiliation: Pulmonary Vascular Diseases Unit, Papworth Hospital, Cambridge, United Kingdom; and.
authors.forename: Joanna
authors.initials: J
authors.lastname: Pepke-Zaba
authors.affiliation: Department of Cardiothoracic Surgery, Papworth Hospital, Cambridge, United Kingdom.
authors.forename: David P
authors.initials: DP
authors.lastname: Jenkins
authors.affiliation: National Pulmonary Hypertension Service, Imperial College Healthcare NHS Trust, Hammersmith Hospital, London, United Kingdom; National Heart & Lung Institute, Imperial College London, London, United Kingdom; l.howard@imperial.ac.uk.
authors.forename: Luke S
authors.initials: LS
authors.lastname: Howard
mesh_terms: D000368:Aged; D000959:Antihypertensive Agents / Q000008:administration & dosage*; D002908:Chronic Disease; D015444:Exercise; D005080:Exercise Test / Q000187:drug effects*; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011655:Pulmonary Embolism / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology*; D011659:Pulmonary Gas Exchange / Q000187:drug effects*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016896:Treatment Outcome
chemical_list: D000959:Antihypertensive Agents
keywords: cardiopulmonary exercise testing; chronic thromboembolic pulmonary hypertension; pulmonary arterial hypertension drug therapy