Results of chromosomal analysis in fetuses with cardiac anomalies as diagnosed by first- and early second-trimester echocardiography.

Chromosomal analyses were performed in 36 fetuses with cardiac anomalies diagnosed by echocardiography at 11 + 1 to 15 + 6 weeks of gestation. Karyotyping was successful in 35 cases and 17 (48.6%) had anomalies, including five with Turner's syndrome, seven with trisomy 18, four with trisomy 21 and one with triploidy. The commonest cardiac anomaly observed in trisomy 21 was a complete atrioventricular canal; in trisomy 18 was ventricular septal defect; in Turner's syndrome was a hypoplastic aortic arch in combination with hypoplasia of the left ventricle and left ventricular outflow tract; and in the case of triploidy was a ventricular septal defect. These findings confirm the opinion that, in fetuses with chromosomal anomalies, there is a high incidence of cardiac defects. Furthermore, there is a distinct pattern of cardiac defects associated with each chromosomal anomaly.