OBJECTIVE: This study aims to determine reference curves for fetal atrioventricular valve areas by means of three-dimensional ultrasound using the spatiotemporal image correlation (STIC) software. METHODS: This was a cross-sectional prospective study on 328 normal fetuses between the 18th and the 33rd weeks of pregnancy. In order to obtain valve areas, the four heart chambers plane was used with the fetus in a dorsal posterior position. To construct reference ranges, a linear regression model was used, adjusted according to the coefficient of determination (R(2)). To calculate the reproducibility of the tricuspid valve area, the intraclass coefficient correlation (ICC) was used. RESULTS: The mean areas of the tricuspid and mitral valves ranged from 0.19 ± 0.08 and 0.20 ± 0.10 cm(2) in the 18th week to 0.93 ± 0.31 and 1.06 ± 0.39 cm(2) in the 33rd week, respectively. The intra-observer and interobserver reproducibility was excellent with ICC = 0.997 and 0.933, respectively. CONCLUSIONS: Reference curves for fetal atrioventricular valve areas were determined and presented good reproducibility.
OBJECTIVE: This study aims to determine reference curves for fetal atrioventricular valve areas by means of three-dimensional ultrasound using the spatiotemporal image correlation (STIC) software. METHODS: This was a cross-sectional prospective study on 328 normal fetuses between the 18th and the 33rd weeks of pregnancy. In order to obtain valve areas, the four heart chambers plane was used with the fetus in a dorsal posterior position. To construct reference ranges, a linear regression model was used, adjusted according to the coefficient of determination (R(2)). To calculate the reproducibility of the tricuspid valve area, the intraclass coefficient correlation (ICC) was used. RESULTS: The mean areas of the tricuspid and mitral valves ranged from 0.19 ± 0.08 and 0.20 ± 0.10 cm(2) in the 18th week to 0.93 ± 0.31 and 1.06 ± 0.39 cm(2) in the 33rd week, respectively. The intra-observer and interobserver reproducibility was excellent with ICC = 0.997 and 0.933, respectively. CONCLUSIONS: Reference curves for fetal atrioventricular valve areas were determined and presented good reproducibility.