Performance of allografts and xenografts for right ventricular outflow tract reconstruction

Background. We compared the long-term durability of allografts and xenograf ts implanted for reconstruction of the right ventricular outflow tract. Methods. A total of 401 patients were studied from January 1974 to June 200 0 (145 xeno- and 256 allografts), follow-up being 98% complete. We analyzed freedom from reoperation and allograft specific factors that may indicate degeneration. Results. The age at implantation was 2 days to 31 years (median 4.0 years). Conduit exchange rate was similar (p = 0.2) for conduit diameters less tha n 15 mm (41% +/- 9% for allografts, 30% +/- 6% for xenografts), but signifi cantly different (p = 0.02) for diameters of 15 mm or larger (60% +/- 8% fo r allografts, 30% +/- 10% for xeno- grafts). Diagnosis-related 20-year surv ival analysis showed a significantly (p = 0.01) better survival of patients with tetralogy of Fallot/pulmonary atresia (83% +/- 5%) and Rastelli-type surgery (81% +/- 8%) compared with patients with truncus arteriosus communi s (69% +/- 8%). ABO-compatibility, preservation method, and aortic or pulmo nary allograft could not be identified as risk factors for allograft longev ity. Conclusions. For smaller diameters (less than 15 mm), allografts exhibit no advantage over xenografts, whereas in larger diameters (15 mm or larger) a llografts are the conduit of choice for the right ventricular outflow tract . (C) 2001 by The Society of Thoracic Surgeons.