title: [Noninvasive, indirect measurement of pulmonary artery pressure].
abstract: OBJECTIVE
  The gold standard for measuring pulmonary artery pressure (PAP) is right heart catheterization. However, the usefulness of this technique is limited in patients with lung disease because of a poor acoustic window. The aim of this study was to assess PAP in a group of healthy persons using a noninvasive, indirect measurement procedure derived from the venous return flow velocity wave.
  
  
  METHODS
  Twenty-three healthy volunteers with a mean (SD) age of 34 (9) years were evaluated. Measurements were made with a Hitachi EUB 5000 ultrasound device (3.5 MHz wave). The subject was placed in supine decubitus with neck hyperextended and head turned to one side. B-mode images were used to locate the point in the internal jugular vein 1 cm higher than its union with the subclavian vein. A color flow image was obtained of the vessel and a pulsed wave was then used to measure velocities. After 5 identical cycles, an estimate of PAP was derived from the ratio of maximum diastolic and systolic flow rates.
  
  
  RESULTS
  On the right side, the mean (SD) ratio between flow rates was 0.50 (0.08), corresponding to a mean PAP of 15 (2.4) mm Hg. On the left side, the ratio was 0.55 (0.09), corresponding to a mean PAP of 16 (2.8) mm Hg. The nonsignificant difference between mean PAP values on the right and left was 1.3 (3.1) mm Hg, and higher values were on the left.
  
  
  CONCLUSIONS
  Mean PAP values obtained with the described procedure are within the normal range for a healthy population. Transcutaneous venous Doppler ultrasound is useful for estimating PAP in healthy individuals.
authors.affiliation: Departamento de Neumología, Hospital de la Santa Creu i de Sant Pau, Facultad de Medicina, Universidad Autónoma de Barcelona, Barcelona, Spain. isabeldoctora@yahoo.es
authors.forename: Isabel
authors.initials: I
authors.lastname: Blanco Vich
authors.forename: José
authors.initials: J
authors.lastname: Belda Ramírez
authors.forename: Pere
authors.initials: P
authors.lastname: Casan Clarà
mesh_terms: D000328:Adult; D001795:Blood Pressure Determination / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011651:Pulmonary Artery / Q000502:physiology*