The meaning of checking the ankle and arm index

The article is professionally consulted by Dr. Phan Dinh Thuy Tien - General Internal Medicine - Department of Examination & Internal Medicine - Vinmec Nha Trang International General Hospital.

The ankle-brachial index test is a noninvasive, rapidly performed means of screening as well as diagnosing peripheral artery disease. This is a condition that occurs when the arteries are narrowed, reducing blood flow to the extremities, causing leg pain when walking and increasing the risk of heart attacks and strokes.

The Ankle-Brachial Index (ABI) is a simple test to compare blood pressure in the upper and lower extremities. Doctors calculate this number by dividing the blood pressure in the artery at the ankle location by the blood pressure in the brachial artery. If the ratio is less than 0.9, this result could mean that a person already has peripheral artery disease in the blood vessels in the legs. The mechanism of peripheral artery disease is when plaque builds up in the arteries, affecting the vessels that carry blood to the legs. Reduced blood flow can cause pain and numbness, most noticeable when walking or exercising a lot. A low ankle-brachial index result can mean when the legs and feet are not getting the blood flow they need. However, this number will not show exactly which blood vessels have narrowed or blocked.

The doctor will need to order an ankle-brachial index test when the patient is considered to be at risk for peripheral artery disease, suggesting the following factors:
Smoking Diabetes Sugar Over 70 years of age Dyslipidemia Known plaque formation in other arteries, such as the coronary arteries in the heart Difficulty palpating the pulse in the legs At this time, checking the ankle-brachial index is aimed at to confirm the diagnosis of peripheral artery disease and prevent its progression and complications, as well as further identify comorbidities in individuals at high risk for coronary artery disease, assess the risk of future heart attack or stroke.
In addition, patients should also have an ankle-brachial index periodically to check the severity of peripheral artery disease, assess whether the condition is getting worse, and consider intervention. if indicated.

3.1 Preparation The patient does not require any special preparation before performing the ankle-brachial index test. Specifically, the patient was still active and had a normal diet on the day of the examination. Also, the patient does not need to stop taking any medications prior to the procedure.
However, it is essential that the sick person should wear loose, comfortable clothing before coming to the hospital. This will allow the technician to easily reach and place the blood pressure cuff on the arm and ankle. For accurate data collection, the patient should be rested for at least 15 to 30 minutes before the procedure as well as not using stimulants that can increase blood pressure, including smoking, drinking tea. , the coffee.
3.2 Procedure The ankle-brachial index measurement is very similar to that of a regular blood pressure measurement, but it needs to be done at two different locations with the following step-by-step procedure:
The patient lies flat on the examination table The technician will place a blood pressure measuring tape at the position just above the patient's ankle. At the same time, the technician will place an ultrasound probe through the artery, which determines the blood flow through the vessel. The blood pressure cuff will be inflated until the ultrasound shows that the bleeding stops. This can be a little uncomfortable for the patient but will be completely painless. The technician will slowly release the pressure in the cuff. The ankle systolic pressure is recorded as the pressure at which blood flow is detected. The technician will repeat this process on the ankle of the other leg and on both arms of the patient. Next, the technician will calculate the ankle-brachial index. The numerator is the ankle systolic pressure on the higher side. The denominator is the upper arm systolic blood pressure. Sometimes the doctor needs to order an ankle-brachial index measurement after exertion. At this time, an ankle-brachial index was recorded before and immediately after the patient jogged on a roller mat or rode a bicycle, to assess how exertion would alter this index.
3.3 Finish The patient can completely return to normal activities immediately after checking the ankle-brachial index.
Since this procedure poses no risks, the patient does not need to stay for further follow-up and can leave immediately.

The normal ankle-brachial index ranges from 1.0 to 1.4. This means that the blood pressure in the arteries in the ankle is usually higher than in the arm.
If the ankle-brachial index is above 1.4, it indicates a calcification in the lower extremity artery. Indeed, in patients with diabetes or the elderly, the limb vessels may be fibrotic or calcified. In this case, the artery may have a higher resistance against the pressure in the cuff and signal may be heard at high pressure, resulting in elevated ankle blood pressure values.
If the ankle-brachial index is less than 0.9, it will be considered as evidence for the diagnosis of peripheral artery disease. When this value is less than 0.5, it indicates severe peripheral artery disease. In such severely ill people there may not be enough blood to heal a sore or surgical wound; Therefore, they should be considered for revascularization if the ulcer does not heal.
In addition, if peripheral artery disease has been diagnosed, the patient needs to adhere to the following:
Stop smoking Treat high blood pressure Well control blood cholesterol levels, blood sugar Take medicines to to increase blood flow to the legs or to prevent blood clots Stay physically active Eat healthy, high-fiber foods like green vegetables, fruits; Limit animal fats and oils.

In a nutshell, the ankle-brachial index is the systolic blood pressure at the ankle divided by the systolic blood pressure in the arm. It has been shown to be a specific and highly sensitive metric for diagnosing peripheral artery disease as well as predicting mortality and other cardiovascular events. Therefore, if you or a loved one has high risk factors for cardiovascular disease such as smoking, hypertension, diabetes, you should actively screen for peripheral artery disease with ankle index. - arm before the unfortunate incident.
Vinmec International General Hospital is one of the hospitals that not only ensures professional quality with a team of leading medical doctors, a system of modern equipment and technology. The hospital provides comprehensive, professional medical examination, consultation and treatment services, with a civilized, polite, safe and sterile medical examination and treatment space. Customers when choosing to perform tests here can be completely assured of the accuracy of test results.

Article references sources: mayoclinic.org, stanfordmedicine25.stanford.edu, hopkinsmedicine.org