Why do a treadmill exercise test?
The most common symptom of peripheral arterial disease (PAD) is intermittent claudication (pain in lower extremities with walking). Muscles that have sufficient blood flow under resting conditions may not have sufficient circulation when exercise increases the muscles’ demand for oxygen-rich blood. As a result, patients with claudication experience pain, aching or fatigue in their lower limb muscles when they walk.
A measurement of how much arterial flow you are getting to your legs is determined by obtaining an ankle to brachial index, which is the ratio of the arterial blood pressure at the ankle divided by the blood pressure in the arm. This is a simple, painless, non-invasive test that a vascular specialist will perform using continuous wave or duplex Doppler. If your resting ankle to brachial index is within a normal range and no other reason can be found for the pain you are having then the vascular specialist may do a treadmill exercise test in an attempt to reproduce the pain (claudication) you are having. If the pain is from disk disease or some other problem, the blood pressure at your ankle will not drop. If you are having PAD then your blood pressure at the ankle will drop.
How will this be done?
Your vascular specialist will measure your ankle to brachial index again while you are at rest and before exercise begins. You will then be placed on a treadmill usually at approximately a 10-degree incline at 2 miles per hour and walk for 5 minutes or until you begin to experience pain or discomfort (claudication) to the point you cannot continue the test (walk). At this point, you will lie down and the doctor will again check your ankle to brachial index to see if you are having claudication on the basis of poor arterial flow. In a person with normal arteries the pressures will drop but should return to resting pressures in 2 to no more than 4 minutes. If you are having problems with your arteries, your pressures may be low for 4 to 20 minutes before they return to normal. This will likely confirm or exclude peripheral arterial disease as the likely cause of your pain. If pain stops you from walking and your blood pressure is normal within 2 to 4 minutes, whatever caused your pain was not from your arteries.
This test usually takes about 30 minutes.
What if I am having real claudication?
If your treadmill exercise test shows you are having claudication because of peripheral arterial disease, the vascular specialist will be able to determine how far you can walk pain free before the onset of symptoms and establish a baseline for comparison should you have a change in your walking distance with medical therapy or if a recommendation for further intervention is needed.
How do I know if I am a candidate and, if so, how should I prepare?
Treadmill exercise testing may not be appropriate for those who need assistance to walk or who are limited by other medical conditions.
No special preparation is required. However, it is suggested you wear comfortable clothing and walking shoes.
We hope the information on these pages is both informative and helpful, but it is intended for education only. Please do note that no web site, no matter how much information is shared, can replace a consultation with your doctor and a vascular specialist. Medical technology and treatment are continually improving and evolving so before making any decision on treatment, it is always advisable to see your doctor first for a comprehensive evaluation of your vascular disease and other medical conditions.
At the Vascular Center of Wichita Falls, we work closely with your other physicians. If you have concerns about your arteries or veins, contact us. A referral is not necessary to make an appointment.