RISK-FACTORS FOR EARLY DEGENERATION OF ALLOGRAFTS IN PULMONARY CIRCULATION

Objective: The aim of this study was to define risk factors for early degeneration of allografts in pulmonary circulation and to recommend s ome guidelines to minimize them. Methods: Between January 1988 and Mar ch 1995, 202 patients with various types of congenital heart disease r eceived cryopreserved allograft conduits for reconstruction of their r ight ventricular outflow tract. We report on 63 patients receiving all ografts ranging from 9-24 mm size within the first 2 years of life. Re sults: Survivors have been followed for 4-67 months. Survival at 5 yea rs, including hospital mortality, was 66%. Two patients died at reoper ation. Of the patients 19.6% (9/46) had early structural deterioration (SD) of their vascular allografts at a mean of 15.2 months after impl antation. Seven of these have already been reoperated with allograft e xchange. Freedom of reoperation was 66% at 5 years. Infants showed 48% freedom of reoperation at 5 years compared to 90% in the 1-2 years ag e group, while freedom of SD was 59% in infants at 48 months compared to 87% in the 1-2 years age group. Of allografts with SD in the infant group 66% had an allograft size of < 14 mm. In aortic allografts free dom of SD was 62% compared to 93% in pulmonary allografts. Freedom of allograft wall calcification was 46% at 18 months in all patients. In the statistical analysis, only infant age (P = 0.03) and aortic allogr aft (P = 0.02) were shown to be significant risk factors for early SD. Conclusion: The use of pulmonary allografts, avoidance of relatively short and small conduits of < 14 mm in diameter, might improve the dur ability of allografts in infants and small children. Copyright (C) 199 7 Elsevier Science B.V.