OC13.01: First trimester study of fetal heart with 3D/4D echocardiography: is the step forward here yet?

Abstract

To determine what is the value of various novel 3- and 4-dimensional ultrasound (3D/4D US) applications for assessing fetal cardiac anomalies at the first trimester of pregnancy. A group of high risk pregnancies for CHD was selected, at Prenatal Diagnosis Unit, and offered first trimester (13 weeks − 13 weeks + 6 days) double blind detailed echocardiography: family history, diabetes, maternal infections, suspected fetal heart anomaly, major extra cardiac anomaly, abnormal NT. There were 143 cases, examined between Jan 2008 and deck 2010. The cases were scanned by one of the two obstetricians, volumes and digital films stored; eventually the reexamination was performed off-line, by both of them. The dynamic changes in the anatomical structures during the cardiac cycle were displayed using continuously gated, dynamic 3D (4D) echocardiography. STIC and TUI was used. Post processing, multiplanar mode was used. The combination of B-flow with STIC along with the creation of a render image was mandatory, and allowed demonstration of blood vessels and heart chambers. Complete examination by the proposed protocol was possible at 57% cases. The median of scanning time was 24 min on-line examination and 75 min off-line. There were discovered 4 major cardiac anomalies (AV canal, HLHS, TGA, Fallot tetralogy), and there were missed GAT, VSD, RAA with RD, without any cardiac anomaly, A Co. None of the cases was diagnosed strictly due to volumes, but due to prolonging the scan, reexamination for better fetal position, and especially due to Doppler (color or power) imaging. The overall detection rate for CHD did not rise after introducing the protocol for high risk pregnancies in our unit (although enabling examination of the fetal heart in the absence of the patient). Yet, the gestational age at diagnosis went down (median of 4.3 weeks). The exploration is more time-consuming and requires a high level of training of the examiner. Furthermore, in some CHD there are later manifestations of structural and functional changes.