Heart transplantation in infancy

Abstract

The first year of life is the time of greatest hazard for infants with congenital cardiac defects. Surgical techniques have allowed for survival in many infants with lethal cardiovascular anomalies. Yet as many as 10% of all congenital cardiac abnormalities are so extensive that physiologic repair is impossible or associated with a prohibitively high mortality rate.’ The incidence of congenital heart disease in the United States is 1% of all live births. With an annual birth rate of at least 3 million, >3,OOO infants are born in this country each year with lethal defects that could be treated by heart transplantation. Palliative operations prevent deaths in some of these unstable infants, but even in these infants a mortality rate as high as 50% occurs during the first year of life.2 Furthermore, an incremental increase in risk is associated with the palliative procedure itself. Although successful palliation can often prolong life, it usually requires additional operations at older ages, which in many cases are associated with a high mortality.3 The age at which humans acquire immune competence is not established. Several studies have documented immunologic immaturity at birth and in early infancy. 4-6 The greatest risks for patients . with heart transplantation are rejection and infec-