title: Pulmonary hypertension and computed tomography measurement of small pulmonary vessels in severe emphysema.
abstract: BACKGROUND
  Vascular alteration of small pulmonary vessels is one of the characteristic features of pulmonary hypertension in chronic obstructive pulmonary disease. The in vivo relationship between pulmonary hypertension and morphological alteration of the small pulmonary vessels has not been assessed in patients with severe emphysema.
  
  
  OBJECTIVE
  We evaluated the correlation of total cross-sectional area of small pulmonary vessels (CSA) assessed on computed tomography (CT) scans with the degree of pulmonary hypertension estimated by right heart catheterization.
  
  
  METHODS
  In 79 patients with severe emphysema enrolled in the National Emphysema Treatment Trial (NETT), we measured CSA less than 5 mm(2) (CSA(<5)) and 5 to 10 mm(2) (CSA(5-10)), and calculated the percentage of total CSA for the lung area (%CSA(<5) and %CSA(5-10), respectively). The correlations of %CSA(<5) and %CSA(5-10) with pulmonary arterial mean pressure (Ppa) obtained by right heart catheterization were evaluated. Multiple linear regression analysis using Ppa as the dependent outcome was also performed.
  
  
  RESULTS
  The %CSA(<5) had a significant negative correlation with Ppa (r = -0.512, P < 0.0001), whereas the correlation between %CSA(5-10) and Ppa did not reach statistical significance (r = -0.196, P = 0.083). Multiple linear regression analysis showed that %CSA(<5) and diffusing capacity of carbon monoxide (DL(CO)) % predicted were independent predictors of Ppa (r(2) = 0.541): %CSA (<5) (P < 0.0001), and DL(CO) % predicted (P = 0.022).
  
  
  CONCLUSIONS
  The %CSA(<5) measured on CT images is significantly correlated to Ppa in severe emphysema and can estimate the degree of pulmonary hypertension.
authors.affiliation: Department of Radiology, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan. shin4114@mac.com
authors.forename: Shin
authors.initials: S
authors.lastname: Matsuoka
authors.forename: George R
authors.initials: GR
authors.lastname: Washko
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Yamashiro
authors.forename: Raul San Jose
authors.initials: RS
authors.lastname: Estepar
authors.forename: Alejandro
authors.initials: A
authors.lastname: Diaz
authors.forename: Edwin K
authors.initials: EK
authors.lastname: Silverman
authors.forename: Eric
authors.initials: E
authors.lastname: Hoffman
authors.forename: Henry E
authors.initials: HE
authors.lastname: Fessler
authors.forename: Gerard J
authors.initials: GJ
authors.lastname: Criner
authors.forename: Nathaniel
authors.initials: N
authors.lastname: Marchetti
authors.forename: Steven M
authors.initials: SM
authors.lastname: Scharf
authors.forename: Fernando J
authors.initials: FJ
authors.lastname: Martinez
authors.forename: John J
authors.initials: JJ
authors.lastname: Reilly
authors.forename: Hiroto
authors.initials: H
authors.lastname: Hatabu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006976:Hypertension, Pulmonary / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011013:Pneumonectomy; D011379:Prognosis; D011651:Pulmonary Artery / Q000000981:diagnostic imaging*; D011656:Pulmonary Emphysema / Q000150:complications / Q000000981:diagnostic imaging* / Q000601:surgery; D011667:Pulmonary Veins / Q000000981:diagnostic imaging*; D011669:Pulmonary Wedge Pressure / Q000502:physiology; D012129:Respiratory Function Tests; D012189:Retrospective Studies; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed / Q000379:methods*