Fetal heart screening in low‐risk pregnancies

Abstract

The aim of this study was to assess whether a screening program for fetal cardiac malformations is justified in a low-risk population, and which factors influence its accuracy. The fetal heart was evaluated in 7024 pregnant women at 20-22 weeks, and evaluation was repeated at a more advanced gestational age in 9% of cases. Cardiological follow-up was continued postnatally until 2 years of age. The overall prevalence of cardiac anomaly was 0.93%. The incidences of major and minor defects were 0.44% and 0.48%, respectively. There were 23 true positives (0.33%): in 20 cases, the diagnosis was made in the second trimester, and 13 women (65%) chose termination of pregnancy. Seventeen of the 20 cases identified in the second trimester were serious malformations. There were 42 false negatives (0.60%). Of these, 12 had signs of cardiac dysfunction at birth or within the 1st month of life, and three of them died as a result of their cardiac anomaly. There were eight false positives (0.11%), all of a minor type. Six abnormal karyotypes, out of a total of 21 performed in the true-positive group (28.5%), were found. In addition, five of the 42 newborns in the false-negative group had trisomy 21. The overall sensitivity was 35.4%, and 61.3% for major defects. The accuracy in two distinct periods was estimated because the level of experience of the operators was different: sensitivity was 45.2% in period 1 (1986-88) (77.8% for major defects) and 26.5% in period 2 (1989-92) (52.9% for major defects). We conclude that a fetal heart screening program in the obstetric population is justified. It defines a high-risk group for karyotyping, allows planning of delivery in a tertiary center or the choice of terminating the pregnancy for the parents and appears to have a positive cost-benefit ratio. A crucial factor is the level of training and experience of the operators, who need specific teaching support.

Accuracy of Fetal Echocardiography in the Differential Diagnosis between Truncus Arteriosus and Pulmonary Atresia with Ventricular Septal Defect

“…CAT and PA-VSD represent two rare subgroups of conotruncal anomalies particularly difficult to differentiate in fetal life [3,15,16,17]. Our overall diagnostic accuracy was 81%, which is inside the range of 77-96% previously reported [1,2,3,4,18,19], although the GA at diagnosis was lower in our series.…”

Four-dimensional fetal echocardiography with spatiotemporal image correlation (STIC): A systematic study of standard cardiac views assessed by different observers

“…Unfortunately, most population studies regarding the use of ultrasonography to detect congenital heart disease have reported low sensitivities for abnormalities of the great arteries [10,12,13,28,41,42,63,64]. Studies documenting higher detection rates emphasized routine visualization of the outflow tracts in addition to the usual four-chamber view [8,22,24,25,27,32,36,37,[65][66][67].…”

Increased nuchal translucency and congenital heart defects in euploid fetuses

“…Fetal echocardiography in the second or (more recently) the first-trimester of pregnancy has been found to be a promising screening method for CHDs. Evaluation of the four-chamber view of the heart and the outflow tracts in the second-trimester of pregnancy yielded a sensitivity as high as 61% [4,5].…”

“…Combined examination of the four-chamber and outflow tract views of the heart in the second-trimester led to the identification of 61% of the fetuses with CHDs [5]. The detection rate was further increased to 81% when transvaginal ultrasound was used to predict fetal cardiac defects in a small series [6][7][8][9].…”