Immunological and echocardiographic evaluation of decellularized versus cryopreserved allografts during the Ross operation.
OBJECTIVE
Compare the immunological and echocardiographic data of decellularized versus cryopreserved allografts used for RVOT reconstruction during Ross operation.


METHODS
From 16/01/03 thru 07/10/03, 20 Ross operations were performed using decellularized (n=11) or cryopreserved (n=9) allografts. Echocardiography was done at discharge, 1, 3, 6 and 12 months and annually thereafter. Samples for determination of antibodies against HLA class I and II were obtained preoperatively and at days 5, 10, 30, 90 and 180 postoperatively. These samples were tested by the ELISA method in LAT-M dishes (unspecific) for identification of circulating antibodies and the results expressed as mean sample values (Is=DO/cutoff). If positive, LAT-E (specific) was performed and PRA levels determined.


RESULTS
There was no mortality. Cryopreserved allografts showed marked Is values elevations for class I and II antibodies which started at the first month and remained elevated up to 6 months. In contrast, of the patients receiving decellularized allografts, seven remained negative, two patients had only marginal elevation of class I antibodies and two patients showed abnormal elevations of PRA levels. This response happened earlier than in the cryopreserved group, starting on the 5th postoperative day and has returned to baseline levels in one case. Echocardiography showed mild, but significant, elevation of gradients in cryopreserved valves but none in the decellularized.


CONCLUSIONS
Decellularized allografts had normal function up to 18 months and showed important reduction of the immunogenic response when compared to cryopreserved valves.
da Costa
Francisco Diniz Affonso
FD
Santa Casa de Curitiba-PUCPr, Curitiba, paraná, Brazil. fcosta@mps.com.br
Dohmen
Pascal Maria
PM
Duarte
Daniele
D
von Glenn
Cristina
C
Lopes
Sérgio Veiga
SV
Filho
Hermínio Haggi
HH
da Costa
Marise Brenner Affonso
MB
Konertz
Wolfgang
W
D000293:Adolescent; D000328:Adult; D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000502:physiology / Q000601:surgery*; D001705:Bioprosthesis; D002648:Child; D015925:Cryopreservation; D005260:Female; D006680:HLA Antigens / Q000276:immunology; D006349:Heart Valve Diseases / Q000503:physiopathology / Q000601:surgery*; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000379:methods*; D006801:Humans; D007518:Isoantibodies / Q000096:biosynthesis; D008297:Male; D011184:Postoperative Period; D011664:Pulmonary Valve / Q000276:immunology / Q000473:pathology / Q000637:transplantation; D014463:Ultrasonography; D014694:Ventricular Outflow Obstruction / Q000601:surgery
D006680:HLA Antigens; D007518:Isoantibodies