Is an isolated ventricular septal defect detected before 24 weeks on ultrasound associated with fetal aneuploidy?

Whether the isolated VSD (i-VSD) is associated with aneuploidy to the same degree as a more severe heart anomaly is unclear. Our objective was to determine the likelihood of aneuploidy in pregnancies at a tertiary referral center when an i-VSD is detected before 24 weeks.

A retrospective chart review of all detailed anatomy ultrasounds before 24 weeks performed at the University of Kansas Medical Center from 08/23/2006 to 06/07/2012 was conducted. A complete evaluation of the fetal heart was accomplished using gray scale and spectral/color Doppler examinations. The outcomes of each pregnancy were reviewed for any diagnoses of aneuploidy. Odds ratios were calculated.

A total of 4078 pregnancies with complete obstetric and neonatal data were reviewed. The prevalence of an i-VSD was 2.7% (112/4078). The odds ratio of aneuploidy when an i-VSD was present was (OR: 36.0, 95% CI: 5.0, 258.1). This odds ratio remained large when either an abnormal or unknown serum screen was present.

The presence of an i-VSD present before 24 weeks does increase the risk of fetal aneuploidy. Whether a normal serum screen or first trimester screen for aneuploidy negates the association of an i-VSD with aneuploidy still remains undetermined.