title: Hemodynamic evaluation and midterm outcome of aortic valve replacement with size 19 Perimount prosthetic valve.
abstract: BACKGROUND
  We sought to investigate the effect of patient prosthesis mismatch on hemodynamic profile using dobutamine stress echocardiography, and to evaluate midterm survival of patients undergoing aortic valve replacement with 19-mm Perimount (Baxter Healthcare, Santa Ana, California) aortic prosthetic valves.
  
  
  METHODS
  Between December 1, 1999, and August 17, 2005, 147 patients (mean age, 76.8 +/- 5.51 years) had aortic valves replaced with 19-mm Perimount prostheses. Dobutamine stress echocardiography was performed in a subgroup of 24 patients (mean age, 76.6 +/- 5.60 years). Univariable predictors of peak transprosthetic gradient (PTG) under maximum stress, adjusted for resting PTG, were investigated by regression. Survival in the whole cohort was described, and univariable predictors of survival were investigated by Cox regression.
  
  
  RESULTS
  In the stress echocardiography subgroup, cardiac output (p < 0.0001), PTG (p < 0.0001), and effective orifice area index increased significantly (p = 0.002) under stress. Peak transprosthetic gradient under stress was strongly associated with PTG at rest (p < 0.0001). After controlling for PTG at rest, no other variables were associated with PTG under stress. In the whole cohort, mean duration of follow-up was 2.21 years; 23 patients died. Neither body surface area nor effective orifice area index was significantly associated with survival.
  
  
  CONCLUSIONS
  The 19-mm Perimount aortic prosthesis has acceptable hemodynamic performance. Transvalvular gradients were within a clinically acceptable range, both at rest and under stress. These findings suggest that patient-prosthesis mismatch is unlikely to cause a clinically important problem when the prosthesis is used, which is consistent with survival experience in the whole cohort.
authors.affiliation: Bristol Heart Institute, University of Bristol, Bristol, United Kingdom.
authors.forename: Pradeep
authors.initials: P
authors.lastname: Narayan
authors.forename: Barnaby C
authors.initials: BC
authors.lastname: Reeves
authors.forename: Syad I A
authors.initials: SI
authors.lastname: Rizvi
authors.forename: Kayvan
authors.initials: K
authors.lastname: Shokrollahi
authors.forename: Huda
authors.initials: H
authors.lastname: Ismail
authors.forename: Gianni D
authors.initials: GD
authors.lastname: Angelini
authors.forename: Angus
authors.initials: A
authors.lastname: Nightingale
authors.forename: Massimo
authors.initials: M
authors.lastname: Caputo
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging* / Q000401:mortality / Q000601:surgery*; D001705:Bioprosthesis; D015331:Cohort Studies; D025401:Echocardiography, Stress; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000379:methods* / Q000401:mortality; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011474:Prosthesis Design; D011475:Prosthesis Failure; D017755:Prosthesis Fitting; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D016019:Survival Analysis; D013997:Time Factors