title: Impact of pressure recovery in the evaluation of the Omnicarbon tilting disc valve.
abstract: BACKGROUND
  Pressure recovery is not taken into account when calculating trans-prosthetic gradients after mechanical valve replacement using Doppler echocardiography. This may lead to underestimation of valvular performance.
  
  
  METHODS
  Simultaneous measurement of Doppler and direct trans-prosthetic gradients was performed in a circulatory mock loop simulator with physiologic parameters at different heart rates and cardiac outputs for small-sized aortic Omnicarbon tilting disc valves (19 - 21 mm).
  
  
  RESULTS
  In all adjustments the Doppler gradient significantly overestimated the net transvalvular gradient. The amount of pressure recovery averaged 59.3 %.
  
  
  CONCLUSIONS
  Doppler echocardiography does not allow for pressure recovery, which is a significant phenomenon in the hemodynamic function of the Omnicarbon tilting disc valve. Valve performance is much better than expected from Doppler gradients.
authors.affiliation: Clinic for Thoracic and Cardiovascular Surgery, University Hospital Aachen, Medical Faculty RWTH, Aachen, Germany. gdohmen@ukaachen.de
authors.forename: G
authors.initials: G
authors.lastname: Dohmen
authors.forename: C
authors.initials: C
authors.lastname: Schmitz
authors.forename: G
authors.initials: G
authors.lastname: Langebartels
authors.forename: U
authors.initials: U
authors.lastname: Steinseifer
authors.forename: T
authors.initials: T
authors.lastname: Schmitz-Rode
authors.forename: R
authors.initials: R
authors.lastname: Autschbach
mesh_terms: D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000502:physiology* / Q000601:surgery*; D001794:Blood Pressure; D002302:Cardiac Output; D003326:Coronary Circulation; D015150:Echocardiography, Doppler; D006339:Heart Rate; D006350:Heart Valve Prosthesis; D006801:Humans; D008955:Models, Cardiovascular; D011474:Prosthesis Design