Peripheral artery disease
The circulatory system is one of the most important systems
in the human body. It is comprised of the heart, the blood vessels and the
blood. Many people usually pay attention only to the heart and the large
arteries that are above the heart, such as coronary arteries that supply the
heart with blood and carotid arteries that supply the brain with blood.
Therefore, the blood vessels below the heart, which are called peripheral
arteries, are usually neglected. However, these peripheral arteries supply the
kidneys, intestines, arms and legs, and may also be affected by certain
disorder. Peripheral artery disease occurs when the peripheral arteries are
blocked or narrowed due to the formation of the plaque of the accumulated
cholesterol and fatty materials.
Ankle-brachial index is a blood test when certain problem
occurs in the peripheral arteries. The blood pressure is normally measured at
the brachial artery in the crook of the arm. However, when there is a blockage
somewhere in the peripheral arteries, then the pressure at places that are
further from the heart can differ from that in the arm. The ankle-brachial
index evaluates blood pressure from two places. When there is a large
difference between the two blood pressures, that it indicates the presence of
peripheral artery disease.
When a person notices some symptoms of peripheral artery
disease, such as pain or cramping in the calves, thighs, hips or buttocks, as
well as slow-healing wounds on the toes, feet or legs, he/she should have an
ankle-brachial index test. People, who are smokers, or those who have diabetes,
suffer from hypertension or high cholesterol is at high risk to develop
peripheral artery disease. Since this disease sometimes does not show any
signs, it is important for people who are at risk to take an ankle-brachial
index test. This test lasts about fifteen minutes at most and no special
preparation is necessary. The ankle-brachial index is obtained when the highest
pressure at the ankle is divided by the highest pressure at the brachial
Normal level of ankle-brachial index
It is considered that the normal level of ankle-brachial index ranges from 0.90 to 1.30. When the level of ankle-brachial index is under 0.90, it means that the blood has difficulty to normally flow to the legs and feet. The index from 0.41 to 0.90 represents mild to moderate peripheral artery disease, while the index 0.40 and lower represents severe disease. When the ankle-brachial index is over 1.30, it usually indicates stiff, calcium-encrusted arteries.