Use of allografts in the primary repair of Truncus arteriosus in early infancy and replacement of previous conduits revisited

Abstract

The use of allografts in the treatment of complex congenital cardiac disease in early infancy, such as primary repair of truncus arteriosus and their use in replacement of previous conduits, has experienced remarkable expansion and change since our original symposium in 1987. At that time, our interest centered on aortic allografts and to paraphrase our introductory statement “there had been an enormous resurgence in their use” (14). This was due to reports of excellent long-term results of this technique, the advent of cryopreservation and the effects of increased donor availability at that time, secondary to infant transplantation. Since that original report a number of dramatic changes have occurred in the allograft experience and only a few of those initial impressions still hold true. In the current update of our experience, we continue to note excellent long-term results within specific categories. Cryopreservation has been demonstrated to markedly improve availability. However, a donor problem has persisted as increased use has impacted the donor pool. In the case of truncus arteriosus, neonatal repair has become the standard due to the availability of small-sized allografts for pulmonary artery reconstruction, tissue to tissue anastomoses, and the avoidance of pulmonary hypertensive crises by early repair. Experience has demonstrated the superiority of pulmonary allograft over aortic allografts, avoiding problems first noted in our original article with aortic allografts in the infant population. In the case of replacement conduits, again, pulmonary allografts have demonstrated excellent results in all subgroups. Finally, while the original allograft placements in early infancy have provided extended graft survival far beyond the Dacron conduits previously used, methods of patch repair for allograft stenosis, rather than allograft replacement, are possible in selective patients and may avoid subsequent allograft replacement. The entire field of allograft repair of complex congenital cardiac disease has seen significant changes in the past 8 years, none more dramatic than in primary repair of truncus arteriosus and the replacement of previous conduits.