Prenatal echocardiography in Trisomy 18 - the key to diagnosis and further management in the second half of pregnancy.

Abstract

Trisomy 18 is an autosomal chromosomal disorder, which is associated with numerous ranges of congenital anomalies. Purpose of this largest study in Poland was to analyze diagnosis and follow-up of fetuses with the prenatal diagnosis of Trisomy 18 in our tertiary center. The study was conducted in a tertiary center for fetal cardiology. The inclusion criteria comprised fetuses with karyotype of Trisomy 18. Data on number of delivery, number of pregnancy, cardiac and extracardiac diseases, type and date of childbirth, sex, birth date, Apgar score, survival time and autopsy were analyzed. There were 41 fetuses with diagnosis confirmed by amniocentesis: 34 were females, 7 males. CHD was detected prenatally in 73% cases at mean gestational age of 26 weeks. The most common CHD was AV-canal (13 cases, 43%) and VSD (13 cases, 43%). In 1999-2010 the average time to detect a heart defect was 29 weeks, in 2011-2021 it was 23 weeks (p < 0.01, U-Mann-Whitney). IUGR was diagnosed in the 3rd trimester in 29 cases (70%), polyhydramnion in 21 cases (51%). Congenital heart defects in female fetuses with intrauterine growth restriction in 3rd trimester with polyhydramnios and in subsequent pregnancy, regardless of maternal age, were typical prenatal findings for Trisomy 18. Heart defects with incomplete septum such as AVC or VSD (which nowadays can be detected in the 1st half of the pregnancy) were the most common anomaly in Edwards Syndrome. These heart defects did not require intervention in the early neonatal period.