Congenital malformations of the heart represent a major cause of infant deaths in developed countries. In the United States about 20% of deaths under one year of age are due to congenital anomalies and about 1/3 of these are due to abnormalities of the heart. (National Vital Statistics Reports, 2001).

Deaths are not evenly distributed within the various population groups, infant characteristics or the nature of the cardiac anomaly. It is therefore very difficult to generalize the findings without information on the factors which increase or decrease the risk of survival for any of the subgroups.

National data reveal lower mortality rates for white than for non-white infants. In the BWIS among the total of 4390 cases, the all-cause one year mortality was 18.2 %. The BWIS demonstrated a strong effect of low birth weight : for infants with birth weights under 1500 grams the case fatality rate was four times that of infants who weighed over 4000 grams ( 35% vs 8%). A similar difference was present by time of diagnosis: infants diagnosed in the first week of life had the most severe defects and 38% did not survive the first year of life, while infants whose diagnosis was made after 12 weeks of life had the lowest mortality (4%). Other factors such as the asssociated non-cardiac defects, including chromosome abnormalities, also had an important effect. An important effect on infant mortality was that of maternal diabetes which was discovered in separate analyses of that subgroup: (39% vs17.8% ) (Loffredo, 2001)

In these considerations affecting infant survival many factors are evident which deserve greater societal and medical attention to enhance the possibility of preventive interventions.

Selected References