Evaluation of fetal heart anatomy at the end of the first trimester and the beginning of the mid-trimester

Abstract

OBJECTIVE: To evaluate fetal heart anatomy in the late first and in the early second trimester. MATERIALS AND METHODS: The study included 75 fetuses between 11 and 19 weeks' gestation. Exams were performed using transabdominal or transvaginal probes. RESULTS: The proportion of cases successfully visualized to all cases in particular week of pregnancy was following: 11 week--0/1 (0%), 12--1/1 (100%), 13 week--1/1 (100%), 14--18/23 (79%), 15--6/9 (67%), 16--23/27 (86%), 17--4/5 (80%), 18--6/6 (100%), 19--2/2 (100%). In 11 weeks' gestation two ventricles and two atrias could be imaged. Anatomy was seen from 12 weeks' gestation with transvaginal and from 13 weeks' gestation with transabdominal transducers. Two tricuspid regurgitations were detected. The interventricular septum was the most difficult structure to visualize in all cases. The grey scale alone was not sufficient for accurate examination of the heart and it was necessary to use colour Doppler to confirm normal forward flow to both ventricles and to identify outflow tracts. CONCLUSIONS: 1. Successful visualization of the heart in early pregnancy is possible from 12 weeks' gestation with transvaginal and from 13 weeks' gestation with transabdominal probe. 2. Fetal echocardiography between first and second trimester should lead to better understanding of fetal hemodynamics in normal and abnormal fetuses and help to introduce new therapeutic treatment in some cases.