Assessment of Quality of Fetal Heart Views by 3D/4D Ultrasonography Using Spatio‐Temporal Image Correlation in the Second and Third Trimesters of Pregnancy

Objective To assess the quality of fetal heart views by three‐dimensional/four‐dimensional (3D/4D) ultrasonography using spatio‐temporal image correlation ( STIC ) in the second and third trimester of pregnancy. Methods This prospective and cross‐sectional study was conducted at a single referral service for the screening of congenital heart diseases ( CHD s), with pregnant women at 20–30 weeks' gestation with a normal fetal heart. 3D/4D STIC were obtained from the fetal heart screening in the following views: four‐chamber (4C), left and right ventricular outflow tracts ( LVOT and RVOT ), 3 vessels and trachea (3 VT ), aortic arch ( AA ), and ductal arch ( DA ). We categorized the images as satisfactory or unsatisfactory and performed McNemar's test to evaluate the differences between the two‐dimensional (2D) echocardiography and 3D/4D STIC techniques. The inter‐observer concordance was obtained by kappa coefficient. Results The rate of satisfactory fetal heart views using 3D/4D STIC was 54% by using 4 planes (4C, RVOT , LVOT , and 3 VT ) and 14% by using 6 planes (4C, RVOT , LVOT , 3 VT , AA , and DA ). In contrast, 100% of the 2D echocardiography images were satisfactory (McNemar's test, P < 0.001). We observed moderate inter‐observer concordance to both 4‐ and 6 planes (κ = 0.56 and 0.43, respectively). Conclusion The quality of the main fetal heart views by 3D/4D STIC still present some limitations compared with the 2D echocardiography.