Hemodynamic measurements with high frequency ultrasound in mouse fetuses.

<p>Results of Pulsed Wave Doppler ultrasound (PW) measurements in fetal mice. a) mean heart rate across various development stages. Heart rates were positively correlated with gestational age (<i>ρ = </i>0.54, p<0.001). b) Peak flow velocities in the aortic root, pulmonary root and thoracic descending aorta, which were positively correlated with gestational age (<i>ρ = </i>0.51, 0.46 and 0.47 respectively, p<0.001 for all vessels). c–d) Plot of velocities in (c) the proximal innominate artery and (d) the left common carotid artery, comparing results obtained from the simulations and PW measurements. The simulations boundary conditions were set up with thoracic descending aorta PW measurements and Murray’s law alone, without consideration of PW measurements at the innominate and left common carotid arteries. The resulting simulated velocity data at these arteries were then observed to match PW measured ones at all gestational stages and at both arteries, indicating that the use of Murray’s law was appropriate. AAo: ascending aorta root; DAo: thoracic descending aorta; PT: pulmonary trunk root; LCC: left common carotid; Innom: innominate; Sim: simulated; Meas: measured.