REVIEW OF MEDICAL HISTORY
The first step in determining whether a person has Peripheral Arterial Disease (P.A.D.) is to take a thorough medical history. When describing their history, persons with P.A.D. may recount problems with claudication (tiredness, aching, or cramping in the legs when exercising, which is relieved with rest), atrophy (shrinking) of leg tissue and impotence. A clinician can obtain essential information about the potential location of arterial narrowing or blockages by interviewing the person.
PERFORM MEDICAL EXAMINATION
Your physician may do a series of tests to assess symptoms of P.A.D.
- Blood pressure measurement.
- Listen for bruits (abnormal pulse sounds) in extremities.
- Attempt to feel pulses on both sides of extremities.
- Assess skin temperature, color and texture.
- Assess regular/irregular hair pattern.
- Identify lesions or ulcers.
ANKLE-BRACHIAL INDEX (ABI)
The ankle-brachial index (ABI) is the mainstay of non-invasive tests performed to determine whether a person has Peripheral Arterial Disease (P.A.D.). The ABI is a test that involves taking the blood pressure at several locations in the body and doing a simple calculation. First the blood pressure is measured at the brachial artery of each arm using a blood pressure cuff placed around the upper arm. Then the blood pressure is measured in the foot using a blood pressure cuff around the ankle.
These blood pressure values are used to calculate the ABI using the following formula: ABI = BP in ankle / BP in arm
The ABI can be supplemented with an exercise test, which involves having the person walk on a treadmill for a specific length of time or until they begin to feel discomfort. As soon as they stop exercising, the person lies down and the blood pressure is measured in the ankle. This type of testing is particularly helpful in persons who describe symptoms that may be claudication, but have an ABI in the normal range when it is taken while resting.
The exercise test can also be performed by having the person stand by a wall and repeatedly lift their heels up off the floor and then lower them. Repeating the heel raises 30-50 times provides adequate exercise to determine whether the ABI changes with activity.
PULSE VOLUME RECORDING AND SEGMENTAL PRESSURES
Two additional non-invasive tests may be done to determine where an artery is occluded. The blood pressure can be tested in various locations along the limb (segmental pressures) and compared to help identify the location of a blockage. Similarly, the pulse volume can be measured and the contour and magnitude of the waves can be tracked. When performed together, these two tests are almost as accurate as an angiography. A Doppler probe can also be used to measure the velocity of blood flow which can be useful in detecting lesions that reduce blood flow or blood pressure. These tests are especially helpful in evaluating the arteries of persons with diabetes, since their arteries may not compress well enough to obtain accurate ABI of segmental pressure readings.
ULTRASOUND DUPLEX SCANS
When clinicians wish to determine the precise location of an occlusion or need to understand more about the features and severity of Peripheral Arterial Disease (P.A.D.) lesions, they can use ultrasonic duplex scanning. This is another non-invasive method. It can provide clinicians with information about the thickness of artery walls, blood vessel structure, blood flow velocity, and blood flow turbulence.
MRI SCANS & CT SCANS
Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) scans may be performed prior to surgical interventions in some persons.
MAGNETIC RESONANCE IMAGING
Using MRI to look at blood vessels and the flow of blood is referred to as a Magnetic Resonance Angiography. A MRA evaluates many arteries in the body and can find problems within the arteries and veins such as stenosis (abnormal narrowing), occlusion and aneurysms.
A CT Scan is a special X-ray test that produces images of your body using x-rays and a computer. The scan allows a physician to visualize internal structures in cross section rather than overlapping images.