title: Durability of porcine bioroots in younger patients with aortic root pathology: a propensity-matched comparison with composite mechanical roots.
abstract: BACKGROUND
  We present a comparison of porcine bioroot and composite mechanical root replacement in a large series of patients younger than 60 years who required full root replacement for true root pathology.
  
  
  METHODS
  Between 1997 and 2007, we performed 986 aortic root replacement procedures, including 391 porcine bioroots and 515 composite mechanical roots for true root indications. Of these, 504 patients were younger than 60 years old at time of the operation. Porcine bioroots were placed in 138 patients, including 38 St. Jude Toronto Root (St. Jude Inc, St. Paul, MN), 98 Medtronic Freestyle (Medtronic Inc, Minneapolis, MN), and 2 Edwards Prima (Edwards Lifesciences Inc, Irvine, CA). Standard univariate, logistic regression, Cox regression, and propensity matching techniques were used.
  
  
  RESULTS
  To adjust for baseline differences in risk factor profiles, propensity matching yielded a final matched data set of 128 matched pairs, with no differences in preoperative risk factor profile or indication for operation. Overall 30-day operative mortality was 2.3% for porcine bioroot patients vs 1.6% for mechanical root patients (p = 0.6). Root type did not influence early (odds ratio, 0.8; 96% confidence interval, 0.2 to 3.2) or late mortality (hazard risk, 1.4; 95% confidence interval, 0 0.5 to 3.8). Multivariate predictors of late mortality included (hazard ratio, 95% confidence interval) age in years (1.01; 1.01 to 1.03), chronic renal failure (3.6; 1.1 to 12.6), and preoperative bacterial endocarditis (3.6; 1.1 to 11.8). Freedom from reoperation was similar between groups; however, bleeding events were more common among mechanical root patients.
  
  
  CONCLUSIONS
  Porcine bioroots provide durable midterm to late-term outcomes after aortic root replacement for true root indications and are an appealing alternative in younger patients because they limit morbidity associated with anticoagulant-related bleeding.
authors.affiliation: Division of Cardiovascular Surgery, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA. nimesh.desai@uphs.upenn.edu
authors.forename: Nimesh D
authors.initials: ND
authors.lastname: Desai
authors.forename: Fenton
authors.initials: F
authors.lastname: McCarthy
authors.forename: William
authors.initials: W
authors.lastname: Moser
authors.forename: Wilson Y
authors.initials: WY
authors.lastname: Szeto
authors.forename: Ahmad
authors.initials: A
authors.lastname: Zeeshan
authors.forename: Danielle
authors.initials: D
authors.lastname: Brown
authors.forename: Y Joseph
authors.initials: YJ
authors.lastname: Woo
authors.forename: Alberto
authors.initials: A
authors.lastname: Pochettino
authors.forename: Patrick
authors.initials: P
authors.lastname: Moeller
authors.forename: Joseph E
authors.initials: JE
authors.lastname: Bavaria
mesh_terms: D000328:Adult; D000818:Animals; D001021:Aortic Valve / Q000601:surgery*; D001705:Bioprosthesis; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D013552:Swine