Blood group antigenicity and clinical durability of cryopreserved homografts

Cryopreserved valved homograft has become the conduit of choice for right ventricular outflow tract (RVOT) reconstruction in pediatric cardiac surgery. Aortic homografts have been frequently used in pulmonary position due to lack of pulmonary homografts. An accelerated fibrocalcification may occur particularly when cryopreserved aortic valved homografts are used, more frequently observed in young infants than in older children. Mechanical factors have been demonstrated to have an impact, but more and more evidence have been showing an immune response as the main culprit. ABO blood group incompatibility between receiver and homograft donor may play a central role in this context. This review presents data on the immunological response and its relation to ABO blood group incompatibility as a risk factor implicated in cryopreserved valved homograft failure. (C) 2005 Elsevier Ireland Ltd. All rights reserved.