title: Hemodynamic benefits of the Toronto Stentless Valve.
abstract: We report on 254 consecutive patients (170 male, 84 female) undergoing aortic valve replacement with the Toronto SPV Stentless Valve (St. Jude Medical, Inc., St. Paul, Minn.). Mean age (+/- standard deviation) was 62.1 +/- 11.6 years. Three patients (1%) received sizes 21 or 22 mm, 24 (9%) received size 23 mm, and 227 patients (89%) received sizes 25, 27, or 29 mm. Serial echocardiography was used to assess valve performance during a 3-year follow-up. Mean gradient decreased by 35.8% (p < 0.0001; 95% confidence interval -39.6%, -31.7%) from postoperative values to the 3- to 6-month follow-up and by 6.1% (p = 0.004; 95% confidence interval -10.1%, -2%) at each subsequent interval; effective orifice area increased by 17.2% (p = 0.0001; 95% confidence interval 12.0%, 22.6%) initially and by 4.4% (p < 0.001; 95% confidence interval 1.8%, 7.0%) thereafter. At 2 years of follow-up, mean gradient was 3.3 +/- 2.1 mm Hg and mean effective orifice area was 2.2 +/- 0.8 cm2. Studies on left ventricular mass were carried out on 84 patients. Left ventricular mass decreased by 14.3% (37.8 +/- 57.9 gm; p < 0.0001; 95% confidence interval -53.7, -21.9 gm) and left ventricular mass index decreased by 15.2% (21.1 +/- 30.5 gm/m2; p < 0.0001; 95% confidence interval -29.5, -12.7 gm/m2) from postoperative values to the 3- to 6-month follow-up interval. The reduction in residual gradient and potential regression in left ventricular hypertrophy may have a beneficial prognostic implication. We believe that the unique stentless design of the Toronto SPV Stentless Valve allows this to occur.
authors.affiliation: Sunnybrook Health Science Centre, University of Toronto, Canada.
authors.forename: D F
authors.initials: DF
authors.lastname: Del Rizzo
authors.forename: B S
authors.initials: BS
authors.lastname: Goldman
authors.forename: G T
authors.initials: GT
authors.lastname: Christakis
authors.forename: T E
authors.initials: TE
authors.lastname: David
mesh_terms: D000206:Actuarial Analysis; D000368:Aged; D000369:Aged, 80 and over; D001022:Aortic Valve Insufficiency / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000601:surgery; D018572:Disease-Free Survival; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis / Q000379:methods*; D006439:Hemodynamics; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015607:Stents; D016896:Treatment Outcome