title: Clinical outcome in patients with 19-mm and 21-mm St. Jude aortic prostheses: comparison at long-term follow-up.
abstract: BACKGROUND
  Small-sized prostheses for aortic valve replacement may result in residual left ventricular outflow tract obstruction. Aim of the study was to verify whether implantation of 19-mm versus 21-mm St. Jude Medical standard prostheses (St. Jude Medical, Inc, St. Paul, MN) influences long-term clinical outcome.
  
  
  METHODS
  Two hundred twenty-nine patients who underwent aortic valve replacement with 19 mm (group 1, 53 patients) or 21-mm St. Jude Medical standard prostheses (group 2, 176 patients) were included in the study. Mean follow-up of current survivors was 10+/-4 years.
  
  
  RESULTS
  Operative mortality was 7.5% in group 1 and 8.5% in group 2. At discharge, an important patient-prosthesis mismatch (effective orifice area index < or = 0.60 cm2/m2) was present in 18% of group 1 versus 5% in group 2 (p = 0.004). Among patients with body surface area less than 1.70 m2, such mismatch was present in 15% of group 1 versus 2% of group 2 (p = 0.008). At last follow-up New York Heart Association (NYHA) functional class (p < 0.001), left ventricular mass reduction (p = 0.02), mean (p = 0.002) and peak transprosthetic gradients (p < 0.001), and effective orifice area index (p = 0.005) were significantly better in group 2. Freedom from sudden death (92%+/-5% vs 99%+/-1%, p = 0.01), valve-related death (84%+/-6% vs 90%+/-5%, p = 0.02), and cardiac events (56%+/-13% vs 86%+/-4%, p = 0.008), were significantly lower in group 1. Effective orifice area index was an independent predictor of late cardiac events.
  
  
  CONCLUSIONS
  Although long-term results after aortic valve replacement with small-sized St. Jude Medical standard prostheses are satisfactory, 19-mm valve recipients show a high prevalence of important patient-prosthesis mismatch with less evident functional improvement and higher rate of cardiac events, suggesting a very cautious use of this prosthesis.
authors.affiliation: Divisions of Cardiac Surgery and Cardiology, Cardio-Thoracic Department University of Pisa Medical School, Italy.
authors.forename: Aldo D
authors.initials: AD
authors.lastname: Milano
authors.forename: Marco
authors.initials: M
authors.lastname: De Carlo
authors.forename: Gianclaudio
authors.initials: G
authors.lastname: Mecozzi
authors.forename: Alessandro
authors.initials: A
authors.lastname: D'Alfonso
authors.forename: Giovanni
authors.initials: G
authors.lastname: Scioti
authors.forename: Carmela
authors.initials: C
authors.lastname: Nardi
authors.forename: Uberto
authors.initials: U
authors.lastname: Bortolotti
mesh_terms: D000368:Aged; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging / Q000601:surgery*; D015150:Echocardiography, Doppler; D005260:Female; D005500:Follow-Up Studies; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016016:Proportional Hazards Models; D011474:Prosthesis Design; D016896:Treatment Outcome