Isolated ventricular septal defects demonstrated by fetal echocardiography: prenatal course and postnatal outcome

Objectives: We assessed the natural history of the different types of isolated ventricular septal defects (VSDs) diagnosed by fetal echocardiography and analyzed their postnatal outcomes. Methods: This is a retrospective cohort study of 86 fetuses with isolated VSDs, detected in 7466 sequential echocardiographic examinations. The subtype and size of the VSDs were assessed during fetal life and the following birth. Data on the spontaneous closure of the VSD, need for intervention, additional abnormalities and chromosomal aberrations was analyzed. Results: From the original cohort 75 cases of isolated VSDs with complete data on outcome were further analyzed. Muscular and perimembranous VSDs were found in 85.3 and 14.7%, respectively. Spontaneous closure of the VSDs occurred prenatally in 31/64 and 3/11 of fetuses with muscular VSD and perimembranous VSD, respectively. Spontaneous closure of the VSD by the age of 2 years occurred in 92.2 and 45.5% of cases with muscular and perimembranous VSDs respectively (p = 0.001). Conclusion: Isolated muscular VSDs usually close spontaneously during pregnancy or in the first 2 years of life and probably do not increase the risk for chromosomal aberrations. On the other hand, isolated perimembranous VSDs may need intervention following birth and may be associated with a chromosomal anomaly.