title: The pulmonary capillary wedge pressure accurately reflects both normal and elevated left atrial pressure.
abstract: BACKGROUND
  Pulmonary capillary wedge pressure (PCWP) is routinely used as an indirect measure of the left atrial pressure (LAP), although the accuracy of this estimate, especially under pathological hemodynamic conditions, remains controversial.
  
  
  OBJECTIVE
  The aim of this prospective study was to investigate the reliability of PCWP for the evaluation of LAP under different hemodynamic conditions.
  
  
  METHODS
  Simultaneous left and right heart catheterization data of 117 patients with pure mitral stenosis, obtained before and immediately after percutaneous mitral comissurotomy, were analyzed.
  
  
  RESULTS
  A strong correlation and agreement between PCWP and LAP measurements was demonstrated (correlation coefficient = 0.97, mean bias ± CI, 0.3 ± -3.7 to 4.2 mm Hg). Comparison of measurements performed within a 5-minute interval and those performed simultaneously revealed that simultaneous pressure acquisition yielded better agreement between the 2 methods (bias ± CI, 1.82 ± 1.98 mm Hg). In contrast to previous observations, the discrepancy between the 2 measures did not increase with elevated PCWP. Multiple regression analysis failed to identify hemodynamic confounders of the discrepancy between the 2 pressures. The ability of PCWP to distinguish between normal and elevated LAP (cutoff set at 12 and 15 mm Hg, respectively), as tested by receiver operating characteristics analysis, demonstrated a remarkably high diagnostic accuracy (area under the curve: 0.989 and 0.996, respectively).
  
  
  CONCLUSIONS
  Although the described limits of agreement may not allow the interchangeability of PCWP and LAP, especially at lower pressure ranges, our data support the clinical use of PCWP as a robust and accurate estimate of LAP.
authors.affiliation: Heart and Vascular Centre, Semmelweis University, Budapest, Hungary.
authors.forename: Anikó I
authors.initials: AI
authors.lastname: Nagy
authors.affiliation: School for Technology and Health, Royal Institute of Technology, Stockholm, Sweden; Sri Sathya Sai Institute of Higher Medical Sciences, Bangalore, India.
authors.forename: Ashwin
authors.initials: A
authors.lastname: Venkateshvaran
authors.affiliation: Sri Sathya Sai Institute of Higher Medical Sciences, Bangalore, India.
authors.forename: Pravat Kumar
authors.initials: PK
authors.lastname: Dash
authors.affiliation: Sri Sathya Sai Institute of Higher Medical Sciences, Bangalore, India.
authors.forename: Banajit
authors.initials: B
authors.lastname: Barooah
authors.affiliation: Heart and Vascular Centre, Semmelweis University, Budapest, Hungary.
authors.forename: Béla
authors.initials: B
authors.lastname: Merkely
authors.affiliation: School for Technology and Health, Royal Institute of Technology, Stockholm, Sweden; Department of Cardiology, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Reidar
authors.initials: R
authors.lastname: Winter
authors.affiliation: School for Technology and Health, Royal Institute of Technology, Stockholm, Sweden; Department of Cardiology, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Aristomenis
authors.initials: A
authors.lastname: Manouras
mesh_terms: D000328:Adult; D062185:Atrial Pressure / Q000502:physiology*; D006328:Cardiac Catheterization; D015331:Cohort Studies; D004452:Echocardiography; D005260:Female; D006325:Heart Atria; D006439:Hemodynamics; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis; D008297:Male; D058386:Mitral Valve Annuloplasty; D008946:Mitral Valve Stenosis / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery; D011446:Prospective Studies; D011669:Pulmonary Wedge Pressure / Q000502:physiology*; D015203:Reproducibility of Results; D055815:Young Adult