By R. Clement Darling III, MD*
People who have peripheral arterial disease (PAD) commonly suffer from atherosclerosis (hardening of the arteries). Smoking is the number one risk factor for PAD.
In atherosclerosis (hardening of the arteries), excess cholesterol, fat and calcium are deposited on the wall of the blood vessels, causing the arteries to become narrowed. This blockage limits the red cells that carry nutrients and oxygen to the muscles. When you walk, you need five times the amount of oxygen than when you stand still. If your muscle runs out of oxygen, it gets full of metabolites or waste products and runs out of oxygen, which causes the legs (especially the calves) to feel tired, cramped and heavy. This disease process is called claudication, (suitably named after the Emperor Claudius of Rome who walked with a noticeable limp).
What is claudication?
Claudication is a cramping muscle pain that is brought on by exercise and relieved by brief periods of rest. This happens when the muscle’s requirements for oxygen and nutrients exceed what the circulatory system is capable of delivering. The cramping is generally located in the calf, thigh, or buttocks and varies from a slight ache to severe cramp-like pain. With vascular claudication, you don’t have good days and bad days and it should take the same distance to reproduce the pain in the muscle group. Usually, after the patient stops, the pain and discomfort will dissipate and return to baseline. This is more lifestyle limiting, as it causes discomfort but there is little risk of severe complications.
Luckily, patients tend to build up these blockages over a long period of time and thus their leg has built up “collaterals” or smaller arterial pathways around these blockages. Initial therapy is directed at risk factor modification and exercise. Walking is good for the patient despite the discomfort it causes. Walking helps to develop collaterals around the blockages but risk factor modifications such as: smoking cessation, weight loss, blood pressure control, as well as lowering you cholesterol are also extremely important.
If the patient is incapacitated by the pain, then further investigation can be performed in select cases; however, this usually occurs after conservative treatment has not given adequate relief to the patient.
What is critical limb ischemia?
In patients with more severe blockages, patients’ blood supply can be so bad that they have pain at rest (pain in their forefoot that wakes them up from sleep), ulcers, or even gangrene. This is termed critical limb ischemia (CLI) and these patients need to have their blood flow evaluated and treated or this could result in amputation.
First, the patient needs to have the blood flow evaluated to localize the blockage. This can be done with non-invasive studies that give your vascular doctor an idea of the severity and location of the blockage. If severe enough, the patient may require an “intervention” such as an angiogram (much like a cardiac catheterization but for the legs), which involves placing a catheter in the artery to specifically localize the blockage and potentially treat the blockage with a balloon angioplasty or stent. In some cases the patient may need a bypass to bring blood flow around the blockages. Once the blood supply is restored, the ulcers will receive the nourishment and oxygen they need to heal. Wound care and close follow up is important in achieving optimal results.
Also, patients with PVD are at higher risk for cardiac events. Controlling your risk factors such as quitting smoking, lowering your cholesterol, blood pressure control, and maintaining a healthy vascular diet will minimize your risk of potential complications from “hardening of the arteries.”
If you have any of these symptoms it is important to see your primary care physician to get a referral to a vascular surgeon or interventionist. They can schedule non-invasive testing that will give both you and them a baseline of where you are at and if your symptoms are related to poor circulation.
*Dr. Darling is Professor of Surgery, Albany Medical College; Chief, Division of Vascular Surgery, Albany Medical Center Hospital; Director, The Institute for Vascular Health and Disease; and President, The Vascular Group, 391 Myrtle Avenue, Suite 5, Albany; albanyvascular.com.