When demand for oxygen in the myocardium is increased, the vascular resistance of the coronary arteries has the ability to reduce, and this can increase the volume of blood passing through the blood vessels.
This reduction occurs because the arteries dilate, which causes an increase in the diameter of the lumen.
[2][3] The greatest potential for this change is normally in the branches (arterioles) of the coronary artery that penetrate the myocardium, rather than those on the surface of the heart.
[1] Coronary flow reserve can be measured through a variety of methods, including digital subtraction cineangiography with coronary catheterization,[4] doppler echocardiography,[5] and positron emission tomography (PET).
[3] In patients with Anderson-Fabry disease, there is evidence to suggest that CFR can be reduced.