Homografts and Xenografts for Right Ventricular Outflow Tract Reconstruction: Long-Term Results

Abstract

Cryopreserved valved homografts are the most commonly used conduit for right ventricular outflow tract reconstruction in children. Early need for reoperation owing to accelerated fibrocalcification has been observed in neonates and children younger than 3 years. A valved bovine jugular vein conduit, Contegra, has shown good early results, without early accelerated fibrocalcification even in the very young patients. This study determined long-term results of homografts and midterm results of Contegra grafts, with special emphasis on reoperation rate. Between January 1993 and March 2009, 205 children received cryopreserved aortic homografts (n = 120, 66 blood group compatible [iso] and 54 non-blood group compatible [non-iso]) or Contegra grafts (n = 85, introduced in January 2000) for right ventricular outflow tract reconstruction and were followed from 6 months to 16 years. Primary diagnosis was tetralogy of Fallot (47%), pulmonary stenosis and atresia (19%), and truncus arteriosus (11%). Conduit dysfunction and need for reoperation were evaluated during follow-up. There were no hospital deaths in the homograft group and 2 deaths of conduit-unrelated cause in the Contegra group, During follow-up 3 patients died in the homograft group from graft-unrelated cause, and none died in the Contegra group. Early reoperation as a result of fibrocalcification and stenosis (within 2 years) was required in 1 Contegra graft patient (1.1%) compared with 8 patients in the homograft group (6.7%), all non-iso. Freedom from reoperation for Contegra grafts was 89.0% at 9 years, compared with non-iso homografts 63.0% and iso-homografts 85.7%. Non-blood group-compatible homografts have a significantly higher early reoperation rate than blood group-compatible homografts. Contegra grafts have a very low early reoperation rate and could therefore be used in neonates and children younger than 3 years of age, if a blood group-compatible homograft cannot be found. In children older than 3 years blood group compatibility is less important.