A preliminary study of fetal intelligent navigation echocardiography in the normal fetuses during second and third trimester

Abstract

Objective To investigate the value of fetal intelligent navigation echocardiography (FINE, 5D Heart) in displaying the normal fetal heart structure during 20 to 38 weeks′ gestation. Methods Three-dimensional data of fetal heart during 20 to 38 weeks′ gestation were acquired using volume transducer prospectively. The STIC volume images were post-processed with 5D heart software by three physicians with different levels of echocardiographic examination and the quality of the section images were analyzed. The intra- and interobserver repeatability was analyzed for the qualification of section images. The correlation between the quality of image and gestational age, body mass index, the placenta position, fetal initial plane position were evaluated using univariate and multivariable logistic regression analysis. Results Two hundreds and five cases of pregnant women were included, and 9 cases were excluded.Volume data acquisition was completed in 180 pregnant women, and the image acquisition rate was 91.8%. The data were assessed twice by three observers and qualified 9 section images were gotten in 156-180 cases (degree of qualification 86.7%-100%). The screening images were satisfied in 152 cases (84.4%), dissatisfied with 28 cases (15.6%). The intra-observer agreement by three observers was absolute concord in four chamber view and abdomen/stomach view; excellent in three vessel trachea view(3VT), five chamber view, left ventricular outflow tract view and superior and inferior vena cava view; good in right ventricular outflow tract view, ductal arch view and aortic arch view. The inter-observer agreement by each of three observers was absolute concord in four chamber view and abdomen/stomach view; excellent in superior and inferior vena cava view; excellent to good in five chamber view, left ventricular outflow tract view, right ventricular outflow tract view; good in 3VT, ductal arch view and aortic arch view. In a univariate analysis, the quality of the image was associated with obesity (χ2=15.338, P=0.000), gestational age (χ2=23.356, P=0.000). Multivariable analysis showed that the obesity (OR=5.587, P=0.001) and gestational age (OR=8.843, P=0.000) were factors affecting the quality of the image. The average time spent in post-processing the images for first time by three observers was (2.77±1.39)min, and there was no significant difference among observers (P>0.05). Conclusions Fetal intelligent navigation echocardiography (FINE, 5D Heart) based on STIC volumes can successfully generate 9 standard fetal echocardiography views in 86.7%-100% of fetuses in the 2nd and 3rd trimesters. This method can simplify examination of the fetal heart and reduce operator dependency. Key words: Echocardiography; Fetal heart; Spatiotemporal image correlation; Fetal intelligent navigation echocardiography(FINE)