title: Rate of progression and functional significance of aortic root calcification after homograft versus freestyle aortic root replacement.
abstract: BACKGROUND
  Calcification is an important limitation after aortic root replacement. The aims were to compare the long-term degree and rate of calcification of homografts versus Medtronic freestyle aortic roots to determine the functional consequences and predictive factors.
  
  
  RESULTS
  One hundred sixty-six patients were prospectively randomized to undergo homograft versus freestyle total aortic root replacement. Of those, 98 patients underwent a total of 248 electron beam computed tomography studies at 0.5, 1, 1.5, 2, 3, and 8 years. All patients underwent yearly clinical and echocardiographic follow-up. Calcium scores were measured using Agatston scoring. Mixed effects models demonstrate significantly higher calcium scores in homograft roots than freestyle at 1.5 years (P=0.02), 2 years (P=0.02), and 3 years (P=0.01), with a trend at 1 year (P=0.06) and 8 years (P=0.1). Homograft calcification occurs significantly faster than in freestyle prostheses between 6 months and 3 years after surgery (P=0.02). Calcification occurs at a similar rate thereafter up to 8 years (P=0.3). At 8 years, freedom from aortic valve dysfunction was lower in homografts than freestyle roots (P=0.06). Freedom from reoperation was 93+/-4% in the homograft group versus 100+/-0% in the freestyle group at 8 years (P=0.01). On multivariate analysis, redo surgery (P<0.001), smoking (P<0.01), atrial fibrillation (P=0.001), family history of coronary artery disease (P<0.01), and a degenerative etiology (P=0.02) were predictive of higher calcium scores.
  
  
  CONCLUSIONS
  Homograft roots exhibit significantly higher calcium scores than freestyle roots because of faster early calcification.
authors.affiliation: Department of Cardiac Surgery, Harefield and Royal Brompton NHS Trust, National Heart and Lung Institute, Imperial College London, UK.
authors.forename: Ismail
authors.initials: I
authors.lastname: El-Hamamsy
authors.forename: Mohamed
authors.initials: M
authors.lastname: Zaki
authors.forename: Louis M
authors.initials: LM
authors.lastname: Stevens
authors.forename: Lucy A
authors.initials: LA
authors.lastname: Clark
authors.forename: Michael
authors.initials: M
authors.lastname: Rubens
authors.forename: Giovanni
authors.initials: G
authors.lastname: Melina
authors.forename: Magdi H
authors.initials: MH
authors.lastname: Yacoub
mesh_terms: D000368:Aged; D001021:Aortic Valve / Q000503:physiopathology / Q000601:surgery*; D001705:Bioprosthesis / Q000009:adverse effects*; D002114:Calcinosis / Q000209:etiology*; D002118:Calcium / Q000378:metabolism; D018450:Disease Progression; D005260:Female; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012086:Reoperation; D014184:Transplantation, Homologous; D016276:Ventricular Function
chemical_list: D002118:Calcium