P19.11: Novel technique to assess fetal fractional shortening by two‐dimensional tracking

Abstract

To assess the usefulness of novel 2D tracking technique to measure fetal cardiac fractional shortening automatically (Auto FS) in normal singleton pregnancies. Two-dimensional tracking system to pursue wall motion of fetal heart, AutoFS, was constructed. In this study, temporal changes of AutoFS throughout gestation was studied in normal singleton pregnancies. At first, cardiac motion of the four chamber view was recorded in B-mode and then the AutoFS was calculated. The Region of interest (ROI) was set at a two-third of the wall from apex, in-to-in of the ventricular wall or septum, and tracking was performed. The values measured between the ventricular septum and at left side are defined as L-AutoFS. That at right side is R-AutoFS. We also obtained the value between each ventricular septum, which was defined as Combined-AutoFS. The equipment was Arietta70 (Hitachi). This study was approved by the ethics committee of this facility and was performed upon obtaining the written informed consent of the subject mother. This study was carried out from November 2016 to March 2017. The data was obtained from 68 of singleton fetuses. L-AutoFS decreased significantly with gestational weeks, and R-AutoFS showed the same tendency (Spearman correlation analysis: p=-0.33 and p=-0.64 respectively). Combined-AutoFS showed the same decline as gestational age (p=0.61). Two-dimensional and automatically calculation of fractional shortening was succeeded. This novel technique can assess fetal heart contractility by being combined with both longitudinal and short-axial dimensions. All L- R- and Combined AutoFS showed a trend towards a negative correlation with gestational weeks. Further examination would be needed for clinical usage.