title: Pulmonary function testing in patients with pulmonary arterial hypertension.
abstract: BACKGROUND
  Although previous studies have shown that peripheral airway obstruction can occur in idiopathic PAH (IPAH), pulmonary function tests have not been well-studied in patients with PAH associated with congenital heart disease (CHD-PAH) and connective tissue disease (CTD-PAH).
  
  
  METHODS
  A multicenter prospective study was performed in PAH patients in China. Pulmonary function tests were evaluated in 190 PAH patients.
  
  
  RESULTS
  Total lung capacity (TLC), residual volume (RV) and total airway resistance (Rtot) were similar in PAH patients and controls. However, measures of airflow, including vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in 1s (FEV(1)), FEV(1)/FVC and MEF(50) were decreased in PAH group. Single-breath diffusion capacity for carbon monoxide (DL(CO)) was also decreased in PAH patients. Expiratory flow-volume curves showed reduction and a curvilinear appearance in patients with PAH. Similar changes were observed among the various subgroups of IPAH, CHD-PAH, and CTD-PAH patients. More CTD-PAH patients had abnormal DL(CO).
  
  
  CONCLUSIONS
  Airway obstruction is common in IPAH, CHD-PAH and CTD-PAH patients. CTD-PAH patients have lower DL(CO). Hemodynamics, serum markers and exercise capacity parameters did not correlate well with pulmonary function indices.
authors.affiliation: Shanghai Pulmonary Hospital, Tongji University, Shanghai, China. jingzhicheng@gmail.com
authors.forename: Zhi-Cheng
authors.initials: ZC
authors.lastname: Jing
authors.forename: Xi-Qi
authors.initials: XQ
authors.lastname: Xu
authors.forename: David B
authors.initials: DB
authors.lastname: Badesch
authors.forename: Xin
authors.initials: X
authors.lastname: Jiang
authors.forename: Yan
authors.initials: Y
authors.lastname: Wu
authors.forename: Jin-Ming
authors.initials: JM
authors.lastname: Liu
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.forename: Lei
authors.initials: L
authors.lastname: Pan
authors.forename: Hui-Ping
authors.initials: HP
authors.lastname: Li
authors.forename: Jie-Lin
authors.initials: JL
authors.lastname: Pu
authors.forename: Zhuo-Li
authors.initials: ZL
authors.lastname: Zhang
authors.forename: Yue-Jin
authors.initials: YJ
authors.lastname: Yang
mesh_terms: D000328:Adult; D000402:Airway Obstruction / Q000209:etiology / Q000503:physiopathology*; D000704:Analysis of Variance; D003240:Connective Tissue Diseases / Q000150:complications / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D005080:Exercise Test; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006330:Heart Defects, Congenital / Q000150:complications / Q000503:physiopathology*; D006801:Humans; D006976:Hypertension, Pulmonary / Q000150:complications / Q000503:physiopathology*; D008297:Male; D011446:Prospective Studies; D012129:Respiratory Function Tests; D014797:Vital Capacity / Q000502:physiology