title: Survival after stentless and stented xenograft aortic valve replacement: a concurrent, case-match trial.
abstract: BACKGROUND
  In order to compare the long-term outcome of stented vs stentless aortic xenografts, a non-randomized, concurrent case-match trial was conducted on all consecutive patients operated between January 1992 and April 2000.
  
  
  METHODS
  Two hundred and ninety-two patients had stented (group 1) and 376 stentless (group 2) xenograft aortic valve replacement (AVR). Group 1 patients were older (75.0 +/- 4.1 vs 70.4 +/- 6.7 years, p = 0.01), while male gender and aortic stenosis were equally prevalent. NYHA functional class III-IV (85 vs 78%, p = 0.03) and associated procedures (53 vs 41%, p = 0.01) were more common in group 1. The aortic cross-clamping (79.7 +/- 27.8 vs 96.1 +/- 23.3, p = 0.001) and bypass (91.4 +/- 57.5 vs 128.5 +/- 34.0, p = 0.002) times were shorter in group 1. A case-match analysis identified 113 identical patient pairs, on the basis of age, gender, diagnosis, NYHA class, associated cardiac disease, and valve size.
  
  
  RESULTS
  The early mortality was higher in group 1 (5.3 vs 2.7%, p = 0.3), though not significantly. During follow-up (37 +/- 30 vs 43 +/- 35 months, p = 0.6), 26 late deaths were recorded (10.3 vs 13.6%, p = 0.4). The 8-year survival was comparable (76 +/- 7 vs 75 +/- 5%, p = 0.2), but freedom from cardiac (77 +/- 7 vs 90 +/- 4%, p = 0.02) and from valve-related death (78 +/- 7 vs 91 +/- 4%, p = 0.02) was higher in group 2. Freedom from structural deterioration (99 +/- 1 vs 98 +/- 2%, p = 0.7) and from reoperation (99 +/- 1 vs 95 +/- 3%, p = 0.2) at 8 years was similar. The late functional status was equally satisfactory (NYHA class I-II 92.7 vs 94.7%, p = 0.06).
  
  
  CONCLUSIONS
  The survival free from cardiac and valve-related mortality when stentless xenografts for AVR are used is superior to that achieved with stented grafts. Stentless AVR has the potential of conferring selective survival advantages late after operation.
authors.affiliation: Division of Cardiac Surgery, University of Verona, Verona, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Casali
authors.forename: Stefano
authors.initials: S
authors.lastname: Auriemma
authors.forename: Francesco
authors.initials: F
authors.lastname: Santini
authors.forename: Alessandro
authors.initials: A
authors.lastname: Mazzucco
authors.forename: Giovanni Battista
authors.initials: GB
authors.lastname: Luciani
mesh_terms: D000368:Aged; D001021:Aortic Valve / Q000601:surgery*; D001705:Bioprosthesis; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006349:Heart Valve Diseases / Q000601:surgery*; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D016555:Matched-Pair Analysis; D015607:Stents; D015996:Survival Rate; D013997:Time Factors; D016896:Treatment Outcome