Our bodies need oxygen-rich blood to flow through our arteries, but when fatty plaque builds up in the walls of the arteries, it reduces how much blood can travel through that artery. This condition, called atherosclerosis, can happen in many areas of the body, but when it affects the peripheral parts of your body, such as the arms and legs, it’s called peripheral artery disease, or PAD. People with PAD often experience pain when walking, or even pain at rest if the narrowing of the artery is so much that blood flow to the legs is severely reduced or completely blocked.
Dr. Nizar Hariri, vascular surgeon with ProMedica Physicians Jobst Vascular, explains, “The typical symptom in patients with PAD is that they walk a certain distance, for example a half block, and have to stop because their legs hurt so badly. While at rest, the leg pain diminishes because the muscles have stopped exerting and don’t require as much oxygen. Then they start walking again only to have the pain return after covering the same distance. This muscle pain due to reduced blood flow is called claudication.”
Other symptoms that may arise in people with PAD include a sensation of coldness in the legs and wounds (e.g. on the heels of the feet) that are reluctant to heal. In either case, the same mechanism that causes claudication is at work—inadequate blood flow to the extremities.
Dr. Hariri emphasizes that the same pathology responsible for PAD can also cause strokes or mini-strokes if plaques in the carotid arteries—the main arteries in the neck that supply blood to the brain—either rupture or cause narrowing. “When this disease develops in the neck, it’s much more serious than in the extremities because stroke can be catastrophic. In fact, it’s one of the major causes of death and disability in the US. Unfortunately, atherosclerosis in the neck doesn’t give any warning signs until a stroke occurs. So, if patients have vascular disease, we always check their carotids to make sure there is no blockage in their neck,” he says.
Risk factors for PAD and other atherosclerotic diseases include high blood pressure, diabetes, high cholesterol levels, and smoking. “Genetics can play a role as well, which is why some people develop the condition at a younger age while others develop it when they’re older. Also, the more risk factors you have, the faster the progression and the greater the severity of the disease,” Dr. Hariri says.
The good news is, there are several simple, non-invasive screening tests that doctors can use to identify PAD in patients. One of these is duplex ultrasound, which is used to measure blood flow in the arteries and determine the percentage of narrowing. Another is the ankle-brachial index, or ABI, test, which compares the blood pressure in a patient’s ankle with the blood pressure in his or her arm. If the blood pressure is significantly lower in the ankle compared the arm, there is likely a blockage in the legs. “CAT scan with contrast is also an option, but this approach involves radiation and the contrast dye can be harmful to the kidneys, so we always start with ultrasound,” Dr. Hariri adds.
According to Dr. Hariri, if a blockage is discovered, there are two options for treatment. “The first is to perform an angiogram, which involves guiding a catheter to the blockage and opening the artery with a balloon or stent—much the same as a heart catheterization, only to the lower extremities. The second is an open surgical procedure in which we either enter the affected artery and clean out the blockage or perform a bypass,” he says.
Of course, preventing PAD in the first place is far preferable to treating the condition after it has already developed. That means eliminating or managing the various risk factors. One of the best things people can do to prevent PAD is to avoid or quit smoking. In addition, it’s important to maintain a healthy blood pressure and cholesterol level, control diabetes if you have it, eat a healthy, low-cholesterol diet, and exercise regularly.
While it may seem counterintuitive, routine exercise is also very important for people who already have PAD. “Exercising can be challenging if you have pain in your legs, but doing it will help promote the development of collaterals, natural vascular detours that the body creates to circumvent blockages. The more you exercise, the more of these collaterals your body will make. And if you push yourself for an extra minute or two each time you exercise, you can double your distance in about six months,” Dr. Hariri advises. ❦