title: The relative contribution of prosthetic gradients, systemic arterial pressure, and pulse pressure to the left ventricular pressure in patients with aortic prosthetic valves.
abstract: OBJECTIVE
  aortic valve replacement (AVR) in patients with aortic stenosis reduces the left ventricular (LV) pressure and the LV mass. However, residual LV hypertrophy at follow-up is a common finding with negative prognostic impact. In the present study, we investigate the contribution of the prosthesis (size, type, and gradients) and the load opposed by the arterial system to the mean LV pressure (MLVP).
  
  
  RESULTS
  twenty-five patients with a bileaflet mechanical (n = 12, size 19-27) or stented biological (size 21-25) valve were included. After weaning from bypass, continuous Doppler recordings (transoesophageal transducer) and simultaneous LV and aortic pressure measurements were performed (high-fidelity catheters). The mean prosthesis gradients with catheter or Doppler were moderately correlated to MLVP (R(2) = 0.40 and 0.34, P = 0.002 and <0.0001). In a multiple regression model, the relationship between MLVP and prosthesis gradient, mean blood pressure, and pulse pressure was strong for both mechanical and biological valves. Using catheter prosthesis gradients, we could explain 97% of the variability in MLVP and when using Doppler gradients 91%.
  
  
  CONCLUSIONS
  in the present study of patients with aortic prosthetic valves, we demonstrate the importance of the load opposed by the arterial system for the LV pressure. Our findings suggest that the MLVP can be estimated from easily obtainable Doppler data and blood pressure measurements. In analysing predictors of LV mass regression, morbidity, and mortality following AVR, the equations might be of interest.
authors.affiliation: Department of Clinical Physiology, Sahlgrenska University Hospital, Gothenburg, Sweden. odd.bech-hanssen@klinfys.se
authors.forename: Odd
authors.initials: O
authors.lastname: Bech-Hanssen
authors.forename: Obaid
authors.initials: O
authors.lastname: Aljassim
authors.forename: Erik
authors.initials: E
authors.lastname: Houltz
authors.forename: Gunnar
authors.initials: G
authors.lastname: Svensson
mesh_terms: D000368:Aged; D001021:Aortic Valve / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery*; D001024:Aortic Valve Stenosis / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D001794:Blood Pressure; D015150:Echocardiography, Doppler; D005260:Female; D006350:Heart Valve Prosthesis; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging* / Q000209:etiology* / Q000503:physiopathology; D008297:Male; D018709:Statistics, Nonparametric; D017725:Ventricular Pressure