Cardiac PET has the unique ability to assess coronary flow reserve and coronary endothelial function on the basis of response of blood flow to pharmacological stress and the cold pressor test. Quantitative analysis of coronary vasomotor function is valuable for precise assessment of function and treatment monitoring in the presence of various coronary risk factors. In addition, recent data have shown prognostic value of PET assessment of coronary vasomotor imaging in patients with suspected coronary artery disease. Thus, quantitative analysis of PET has a great potential for wide application in identifying microcirculatory dysfunction and "individualized" monitoring of the effects of primary or preventive medical intervention to optimize cardiovascular outcome.