Abstract: A method and diagnostic apparatus for determining the condition of a patient's artery or arteries by the use of an ultrasound imaging system which operates in the triplex mode, with a B-mode image of a selected artery location, an A-mode perpendicular to the plane of the artery, at the selected location and a pulsed doppler, at the selected location at an angle to the plane of the artery, with the signals combined, the artery physically or chemical stimulated, the percent dilation of the artery is determined after stimulation, and therefore the condition of the artery is obtained.