Highly specific measurements of flow in vessels, such as the coronary artery, can be obtained by processing cubic fundamental information. By showing flow in vessels with a high degree of contrast-to-tissue specificity, ultrasound based 3D contrast agent based coronary artery angiograms may be possible. Measurement and display of the velocity of agent from the cubic fundamental signal is provided simultaneously with display of cubic fundamental energy, such as providing a display map indexed by both energy and velocity. High pulse repetition frequency (PRF) for cubic fundamental detection in conjunction with long velocity measurement intervals may increase low velocity sensitivity and measurement precision. Pulsed wave (PW) Doppler may be improved by using a cubic fundamental sensitive pulse sequence. Using cubic fundamental sensitive techniques with other motion estimation techniques, such as two-dimensional velocity estimation or speckle tracking, may operate better than using other contrast agent detection techniques because of substantially reduced clutter.