Correlation between types of Ventricular Septal Defect and chromosomal abnormalities in Low-Risk Non-Invasive Prenatal Testing

Abstract

Abstract Objective The aim of this study was to examine whether there is any association between various types of ventricular septal defect (VSD) and chromosomal abnormalities in the low-risk environment of non-invasive prenatal testing (NIPT) and to evaluate the prognosis of fetuses with different types of VSD. Methods From May 2017 to May 2022, Tianjin Central Obstetrics and Gynecology Hospital collected cases of prenatal diagnosis of fetal VSD by amniocentesis. Those with NIPT high-risk, such as chromosomal number abnormalities, fragment deletions or duplications, and polymorphisms, were excluded from the study. Data collected included ultrasound classification of VSD, prenatal NIPT results, copy number variations (CNVs) results, and neonatal outcomes. Results This study investigated the prevalence of pathogenic copy number variations (CNVs) in 74 cases, including 45 isolated ventricular septal defects (VSDs) (9 of which were muscular and 36 non-muscular) and 29 non-isolated VSDs (10 with intracardiac and 19 with extra-cardiac structural anomalies). Results revealed that the incidence of pathogenic CNVs was lower in isolated VSDs than in non-isolated VSDs in a low-risk NIPT condition (χ2 = 9.344, P = 0.002). There was no significant difference in the prevalence of pathogenic CNV between VSDs with intracardiac and extra-cardiac structural anomalies (P = 0.541). Moreover, VSDs associated with intracardiac structural anomalies had the highest rate of surgical intervention. Conclusions When NIPT is low-risk and VSD is isolated, the likelihood of fetal chromosomal defects is not increased. However, when there are both intra- and extracardiac structural issues in addition to VSD, the possibility of pathogenic CNV is considerably greater and therefore, invasive prenatal diagnosis is recommended. It was additionally noted that isolated muscular septal defects usually do not require surgery, which can be used as a basis for prenatal counseling regarding fetal VSD.