199: Use of fetal myocardial speckle tracking to predict category 2 tracings prior to maternal pushing

Abstract

To assess the ability of evaluation of the 4-chamber view and the right and left ventricles of the fetal heart to predict the development of a category 2 fetal heart rate tracing prior to maternal pushing in labor. This was a prospective, observational study of 91 women performed at one academic center between January 2018 and January 2019. Patients who were admitted to Labor and Delivery and in labor had an ultrasound performed to collect a 4-chamber view cine loop, fetal biometry, umbilical artery and middle cerebral artery Doppler’s and amniotic fluid volume assessment. The 4-chamber view size and shape were measured. Using speckle-tracking software, the size, shape, as well as the global, longitudinal, and transverse contractility were measured and z-scores computed from 200 normal control fetuses. The fetal heart rate tracings were analyzed during the last 30 minutes prior to full cervical dilatation just prior to maternal pushing. Logistic regression was used to compute the statistics for the receiver-operating curve (ROC) to predict the sensitivity and false-positive rate associated with late decelerations. Sixty-three percent (57/91) had a category 2 fetal heart tracing 30 minutes prior to pushing. Logistic regression analysis identified 1 Doppler variable and 20 cardiac variables for a sensitivity of 91% (52/57) and a false-positive rate of 14.7% (5/34) (Table 1). The Receiver Operator Curve had an area of 0.97(SE=0.03; 95% CI 0.89=01 to 0.995) (Figure 1). Evaluation of the size of the 4-chamber view and ventricular size and shape using speckle tracking analysis may serve as a useful test to determine which fetuses are prone to demonstrate category 2 fetal heart rate tracing during labor prior to maternal pushing. Our study did not have enough patients who required cesarean or operative vaginal delivery to determine if this technology can help to predict this complication. Further studies are warranted to determine the clinical value of speckle tracking as a supplemental tool to fetal heart rate tracings during labor.View Large Image Figure ViewerDownload Hi-res image Download (PPT)