title: Mid-term findings on echocardiography and computed tomography after RVOT-reconstruction: comparison of decellularized (SynerGraft) and conventional allografts.
abstract: OBJECTIVE
  The immune response against human-leucocyte-antigens on donor-cells may be an important factor contributing to the degeneration of allograft-valves. We have previously reported that the use of the decellularized allograft SynerGraft (CryoLife) reduces the immunologic response of the allograft-recipient. In this study we compare the echocardiographic and computed tomography angiographic (CTA) findings of SynerGrafts with conventional cryopreserved allografts.
  
  
  METHODS
  22 patients who received a pulmonary SynerGraft (SG-group) (21 during a Ross-procedure) underwent CTA and resting echocardiography (median: 10 months postoperatively). 47 randomly chosen patients who underwent a Ross-procedure served as controls (C-group) (median: 32 months postoperatively).
  
  
  RESULTS
  Neither the pressure gradients (mean: SG=9+/-4 vs C=10+/-4mmHg; P=0.64) across the allograft, nor the effective orifice area (EOAI) (SG=0.93+/-0.80 vs C=0.93+/-0.42cm(2)/m(2); P=0.96) differed between the groups. The EOAI showed a significant correlation with the smallest allograft-conduit-area measured on CTA (r=0.81; P<0.001) which was most frequently (n=34) found in the proximal postvalvular tubular part of the conduit. Calcifications (n=11) or a fibroproliferative reaction (n=15) were rarely observed. Overall, there were no radiologic differences between the groups. On CTA, the smallest diameter of the allograft-conduits was significantly smaller than the diameter given on the cryopreservation protocol (SG=16+/-3 and C=17+/-3mm vs 25mm in both groups; P<0.001 each) whereas the diameter of the distal part of the allograft was not (SG=24+/-2, P=0.066, and C=25+/-3mm, P=0.82).
  
  
  CONCLUSIONS
  Despite a significant shorter follow-up in the SynerGraft-group, no functional or radiologic differences were observed as compared to control-patients. The smallest diameter is located almost exclusively at the proximal level of allograft-conduits.
authors.affiliation: Department of Cardiac Surgery, Universitaetsklinikum Schleswig-Holstein, Campus Luebeck, Ratzeburger Allee 160, 23538 Luebeck, Germany.
authors.forename: J F Matthias
authors.initials: JF
authors.lastname: Bechtel
authors.forename: Joerg
authors.initials: J
authors.lastname: Gellissen
authors.forename: Armin W
authors.initials: AW
authors.lastname: Erasmi
authors.forename: Michael
authors.initials: M
authors.lastname: Petersen
authors.forename: Alexander
authors.initials: A
authors.lastname: Hiob
authors.forename: Ulrich
authors.initials: U
authors.lastname: Stierle
authors.forename: Hans-Hinrich
authors.initials: HH
authors.lastname: Sievers
mesh_terms: D000328:Adult; D001021:Aortic Valve / Q000601:surgery; D001705:Bioprosthesis; D015925:Cryopreservation; D005260:Female; D005500:Follow-Up Studies; D006085:Graft Survival / Q000276:immunology; D006349:Heart Valve Diseases / Q000601:surgery*; D006350:Heart Valve Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D011475:Prosthesis Failure; D011664:Pulmonary Valve / Q000000981:diagnostic imaging / Q000276:immunology / Q000637:transplantation*; D014057:Tomography, X-Ray Computed; D014183:Transplantation, Heterologous / Q000276:immunology; D014463:Ultrasonography