PURPOSEThere is much controversy about the optimal management of a patent ductus arteriosus (PDA) in preterm infants, with the risk of over- and undertreatment. Ultrafast ultrasound blood flow imaging makes it possible to accurately quantify 2D flow patterns through this fetal channel, whereas conventional Doppler ultrasound is limited to 1D information. It is hypothesized that this new technique will provide new qualitative and quantitative measures, which will potentially enable us to find new parameters to objectively determine the PDA significance and predict its spontaneous closure. So far ultrafast ultrasound blood flow imaging has shown promising results for carotid artery measurements in healthy adults. The purpose of this study is to adjust the acquisition and post-processing algorithms for ultrafast ultrasound blood flow measurements in order to acquire 2D flow images of the heart and fetal channels in newborn infants.METHOD AND MATERIALSSo far, four newborn infants were included in this proof-of-concept study. Within 48 hours after birth, each participant undergoes a conventional Doppler ultrasound exam of the heart, as well as an ultrafast (4000 fps) ultrasound exam. During the course of the study, acquisition as well as post-processing parameters for the ultrafast ultrasound examinations were iteratively optimized to meet the challenging conditions which arise when imaging neonates. The information obtained from the ultrafast measurements is compared to the Doppler measurements to reveal the added value of ultrafast blood flow imaging in the assessment of hemodynamic significance of the PDA.RESULTS2D blood flow measurements of the heart of newborn infants could be obtained and visualized using ultrafast ultrasound, showing additional information when compared to Doppler measurements.CONCLUSIONWith ultrafast ultrasound imaging, 2D velocity vectors in the heart of newborn infants can be visualized. Optimization of this technique will give new information about blood flow patterns before, during and after closure of the ductus arteriosus. This could lead to the establishment of parameters predicting spontaneous closure of the PDA, reducing the risk of over- and undertreatment.CLINICAL RELEVANCE/APPLICATIONUltrafast ultrasound could provide additional blood flow information, which will enable us to find new parameters to predict closure of the patent ductus arteriosus, reducing over- and undertreatment.