Congenital heart disease (CHD) remains the leading cause of infant mortality from birth defects, affecting approximately 1% of pregnancies worldwide. A recent study conducted by researchers at University Hospitals Leuven highlights how chromosomal analysis can play a pivotal role in predicting the short-term outcomes of prenatally diagnosed CHD, providing necessary insights for parents and healthcare professionals.
The study, published on February 1, 2025, emphasizes the complex nature of CHD, which encompasses various types and severities, and the additional risks posed by extracardiac anomalies (ECA). Researchers reviewed the medical files of 341 fetuses diagnosed with CHD at the Leuven hospitals between 2018 and 2021, analyzing the influence of genetic abnormalities and other clinical factors on key outcomes such as the termination of pregnancy and neonatal mortality.
Dr. Verbeke, the lead author of the study, stated, “The results underline the importance of genotyping and accurate cardiac and extracardiac phenotyping for prognostication in fetuses with congenital heart disease.” The study sheds light on how prenatal genetic diagnosis affects clinical decisions; fetuses with high-risk categories or chromosomal disorders showed higher rates of pregnancy termination.
The researchers categorized CHD severity using scores ranging from A to D, with A denoting extremely high risk and D indicating low risk. Their findings indicated significant associations between higher severity scores and adverse outcomes. Notably, the prenatal identification of genetic disorders, particularly those linked with severe syndromes, often led to difficult decisions about continuing pregnancies.
Another key element of the study was the impact of ECA on outcomes. Major ECA, deemed life-threatening, correlated strongly with lower survival rates beyond the age of one month. “Early and accurate prenatal diagnosis of congenital heart disease is pivotal to optimize perinatal care and reduce neonatal mortality,” the authors noted.
The retrospective nature of this study allowed it to focus comprehensively on factors influencing survival rates, providing valuable insights for clinical practices. The majority of pregnancies involved were singleton, with twins and instances of assisted reproductive technology being overrepresented compared to general population statistics.
Findings also demonstrated specific genetic conditions, such as chromosome 22q11.2 deletion syndrome and trisomy 21, as common diagnoses among the cohort. Notably, the diagnostic yield from chromosomal microarray analysis was about 10–15%, highlighting the need for targeted genetic assessments during prenatal care.
The study calls for enhanced prenatal screening strategies, placing emphasis on the integration of advanced genetic testing methods such as non-invasive prenatal testing (NIPT) and chromosomal microarray analysis (CMA), which can help identify conditions before birth.
Concluding their findings, the researchers asserted the importance of thorough prenatal assessment for CHD, stressing its role in providing effective counseling for expectant parents. “A comprehensive genetic diagnosis may lead to improved management strategies and decision-making for families dealing with complex congenital heart diseases,” the researchers added.
This study not only underlines the challenges faced during prenatal diagnosis of CHD but also accentuates the potential benefits of combining genetic insights with clinical evaluations to improve the outcomes for affected infants and their families.