title: A new, simple, and accurate method for non-invasive estimation of pulmonary arterial pressure.
abstract: OBJECTIVE
  To develop and validate a new non-invasive method for the estimation of pulmonary arterial pressure (PAP) based on advanced signal processing of the second heart sound.
  
  
  METHODS
  Prospective comparative study.
  
  
  METHODS
  Referral cardiology centre.
  
  
  METHODS
  This method was first tested in 16 pigs with experimentally induced pulmonary hypertension and then in 23 patients undergoing pulmonary artery catheterisation.
  
  
  METHODS
  The heart sounds were recorded at the surface of the thorax using a microphone connected to a personal computer. The splitting time interval between the aortic and the pulmonary components of the second heart sound was measured using a computer assisted spectral dechirping method and was normalised for heart rate.
  
  
  RESULTS
  The systolic PAP varied between 14-73 mm Hg in pigs and between 20-70 mm Hg in patients. The normalised splitting interval was measurable in 97% of the recordings made in pigs and 91% of the recordings made in patients. There was a strong relation between the normalised splitting interval and the systolic PAP (pigs: r = 0.94, standard error of the estimate (SEE) = 5.3 mm Hg; patients: r = 0.84, SEE = 7.8 mm Hg) or the mean pulmonary pressure (pigs: r = 0.94, SEE = 4.1 mm Hg; patients: r = 0.85, SEE = 5.8 mm Hg).
  
  
  CONCLUSIONS
  This study shows that this new non-invasive method based on advanced signal processing of the second heart sound provides an accurate estimation of the PAP.
authors.affiliation: Quebec Heart Institute/Laval Hospital, Laval University, Ste-Foy, Quebec, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Xu
authors.forename: L-G
authors.initials: LG
authors.lastname: Durand
authors.forename: P
authors.initials: P
authors.lastname: Pibarot
mesh_terms: D001794:Blood Pressure / Q000502:physiology*; D001795:Blood Pressure Determination / Q000379:methods* / Q000592:standards; D006801:Humans; D011446:Prospective Studies; D011651:Pulmonary Artery / Q000502:physiology*; D012680:Sensitivity and Specificity