Ultra-high frequency ultrasound is a powerful live imaging tool to examine cardiac abnormalities in small animals. Its noninvasiveness allows maintaining the physiologic state of embryos. Herein, we show the use of M-mode ultrasound to measure the heart rates of embryos at E18.5 in utero.
Kim, W., Seidah, N. G., Prat, A. In utero Measurement of Heart Rate in Mouse by Noninvasive M-mode Echocardiography. J. Vis. Exp. (81), e50994, doi:10.3791/50994 (2013).