Chromosomal abnormalities and congenital heart disease.

Abstract

In this study the authors attempted to determine the frequency of the classical chromosomal syndromes as a cause of congenital heart disease and sought other cytogenetic abnormalities in patients with congenital heart disease, selected either for the presence of extracardiac abnormalities or the existence of congenital heart disease in other members of the family. Of the 275 patients whose karyotypes were determined, 119 had a known syndrome. A chromosomal aberration, such as trisomy 21, a sex chromosomal aneuploidy, such as XO, XXY, XYY, XXX, or a more complex mosaic was found in 39. Among the other patients of this group, only a patient with Fanconi's anemia showed abnormalities of the karyotype (numerous chromatid and isochromatid breaks). Among 100 other patients with unclassifiable associated malformations, 10 had abnormal karyotypes. The following abnormalities were noted: complex structural rearrangements, minute chromosome fragments, variations in size of the satellites, presence of unusual satellites on chromosome 17, deletion of the short arm of a D-chromosome, lengthening of chromosome 16, and chromosome breaks. The remaining 56 patients were studied for familial congenital heart disease. Two chromosomal abnormalities were detected in this group. If the classical aberrations are included, the frequency of chromosomal abnormalities as a cause of congenital heart disease may be estimated at between 3 and 5%. This figure should be considered in relation to the methods of recruitment which excluded all patients less than 3 years of age.