title: Derivation of mean pulmonary artery pressure from noninvasive parameters.
abstract: BACKGROUND
  The assessment of pulmonary pressure is important for the diagnosis and management of patients with pulmonary hypertension. Mean pulmonary artery pressure (MPAP) has been used in the current definition of pulmonary hypertension. However, invasive derivation by Doppler echocardiography provides the peak pulmonary artery systolic pressure (PASP). The aim of this study was to derive a method to predict MPAP from PASP.
  
  
  METHODS
  Invasive hemodynamic pressures in 307 patients who underwent right heart catheterization were examined. Simple regression techniques were used to determine the relationship between MPAP and PASP in a derivation cohort (n = 198) and a validation sample (n = 109). Bland-Altman analysis was performed to examine predicted versus observed values of MPAP.
  
  
  RESULTS
  MPAP and PASP at catheterization were strongly related over a range of pressures (R(2) = 0.89, n = 198; SE, 4.04; P < .0001). The relation of MPAP to PASP in the derivation cohort (MPAP = 0.61 × PASP + 1.95 mm Hg) was validated in the test sample, with an R(2) value of 0.94 for predicted versus observed MPAP (SE, 2.87; P < .0001). The relationship of predicted versus observed MPAP was constant across different degrees of pressure elevation, as well as different etiologies of pulmonary hypertension. Applying the equation to Doppler-derived pulmonary pressures, there was excellent correlation of predicted MPAP from echocardiography and invasively measured MPAP (R(2) = 0.78, P < .0001).
  
  
  CONCLUSIONS
  MPAP can be accurately predicted from PASP over a wide pressure range for different etiologies of pulmonary hypertension. This finding may help define MPAP noninvasively.
authors: Division of Cardiovascular Diseases and Internal Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
authors: Rachel C
authors: RC
authors: Steckelberg
authors: Andrew S
authors: AS
authors: Tseng
authors: Rick
authors: R
authors: Nishimura
authors: Steve
authors: S
authors: Ommen
authors: Paul
authors: P
authors: Sorajja
mesh_terms: D000368:Aged; D001794:Blood Pressure / Q000502:physiology*; D006328:Cardiac Catheterization; D004452:Echocardiography; D015150:Echocardiography, Doppler; D005260:Female; D006439:Hemodynamics; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis / Q000209:etiology / Q000503:physiopathology; D008297:Male; D011651:Pulmonary Artery / Q000502:physiology*; D012044:Regression Analysis; D013599:Systole / Q000502:physiology