Atherosclerosis is a slowly progressive process and is not always reflected in typical disease symptoms. Sometimes the body responds to blocked blood vessels by forming collaterals, that is vessels that compensate for a blockage by bypassing it. New, but usually smaller supply channels arise all around the damaged area.

The following methods are used for diagnosis:

• Careful documentation of symptoms
• Clinical examination, including arm and leg pulses and blood pressure
• Exercise tests in patients with coronary atherosclerosis
• Doppler ultrasound to visualise the vessel walls and the degree of narrowing. Examination of the back of the eye shows changes in the retinal vessels that may signal atherosclerosis.
• Laboratory tests: Atherosclerotic cardiovascular disease is directly related to metabolic disturbances. Both high LDL cholesterol and low HDL cholesterol indicate increased risk.
• Using invasive angiographic techniques it is possible to assess the degree of vascular stenosis. The value of intracoronary ultrasound for evaluating coronary plaque structure in atherosclerosis is also currently under study.