Peripheral artery disease
The circulatory system is one of the most important systemsin the human body. It is comprised of the heart, the blood vessels and theblood. Many people usually pay attention only to the heart and the largearteries that are above the heart, such as coronary arteries that supply theheart with blood and carotid arteries that supply the brain with blood.Therefore, the blood vessels below the heart, which are called peripheralarteries, are usually neglected. However, these peripheral arteries supply thekidneys, intestines, arms and legs, and may also be affected by certaindisorder. Peripheral artery disease occurs when the peripheral arteries areblocked or narrowed due to the formation of the plaque of the accumulatedcholesterol and fatty materials.
Ankle-brachial index is a blood test when certain problemoccurs in the peripheral arteries. The blood pressure is normally measured atthe brachial artery in the crook of the arm. However, when there is a blockagesomewhere in the peripheral arteries, then the pressure at places that arefurther from the heart can differ from that in the arm. The ankle-brachialindex evaluates blood pressure from two places. When there is a largedifference between the two blood pressures, that it indicates the presence ofperipheral artery disease.
When a person notices some symptoms of peripheral arterydisease, such as pain or cramping in the calves, thighs, hips or buttocks, aswell as slow-healing wounds on the toes, feet or legs, he/she should have anankle-brachial index test. People, who are smokers, or those who have diabetes,suffer from hypertension or high cholesterol is at high risk to developperipheral artery disease. Since this disease sometimes does not show anysigns, it is important for people who are at risk to take an ankle-brachialindex test. This test lasts about fifteen minutes at most and no specialpreparation is necessary. The ankle-brachial index is obtained when the highestpressure at the ankle is divided by the highest pressure at the brachialartery.
Normal level of ankle-brachial index
It is considered that the normal level of ankle-brachialindex ranges from 0.90 to 1.30. When the level of ankle-brachial index is under0.90, it means that the blood has difficulty to normally flow to the legs andfeet. The index from 0.41 to 0.90 represents mild to moderate peripheral arterydisease, while the index 0.40 and lower represents severe disease. When theankle-brachial index is over 1.30, it usually indicates stiff,calcium-encrusted arteries.