A disproportionately high incidence of symptomatic coarctation of the aorta in white infants in the Transvaal.

A retrospective study of Johannesburg Hospital records revealed that during a 4-year period (1978-1981) 49 infants who had been born in the Transvaal had presented with symptomatic coarctation of the aorta in the first year of life. The total number of live births for this period was 92,697. This incidence of 0.529 new cases per 1,000 live births, or 1/1,892 births, is three times higher than that observed in a careful study in the USA. The age at presentation and sex ratio were similar to other reported series. There was no definite seasonal incidence. Two of the patients had siblings with coarctation of the aorta. The exact reasons for the unusually high number of cases which occurred in the years 1979 and 1981 (1/1,405 and 1/1,241 live births respectively) could not be determined. It is suggested that it is probably due to a combination of genetic predisposition and as yet unidentified environmental factors.