Associations between congenital heart defects and genetic and morphological anomalies. The importance of prenatal screening

Abstract

Aim: To study congenital heart defects (CHDs), evaluate their relation to extra-cardiac pathologies, and assess the significance of prenatal diagnostics for heart diseases.

Methods: Data from 1999-2017 were analyzed for the incidence of significant CHDs in fetuses (prenatal ultrasound/echocardiography) and children, including, where applicable, autopsy data and genetic evaluation.

Results: Among 220,400 fetuses, 819 (3.7 cases per 1000) significant CHDs were observed. Of the total, 53% (435/819) of CHDs were diagnosed prenatally. The heart defect was an isolated impairment in 78% (640/819), associated with a genetic impairment in 16% (128/819), and with extra-cardiac malformations without genetic pathology in 6% (51/819). Chromosomal aberrations were diagnosed prenatally in 70% (90/128) of those affected and extra-cardiac conditions in 86% (44/51). The CHD and genetic pathology association was more frequent prenatally [21% (90/435) vs. postnatally: 10% (38/384; P<0.0001)], as was the association between CHD with other extra-cardiac pathology and a normal karyotype [prenatally: 10% (44/435) vs. postnatally: 2% (7/384; P<0.0001)].

Conclusion: Heart defects are most frequently isolated, with genetic and other extra-cardiac anomalies in about one third of cases, significantly linked to prenatal diagnostics.

Keywords: aneuploidy; congenital heart defect; extracardiac malformation; fetal echocardiography; genetic abnormality; screening.