When we hear the word "atherosclerosis," the buildup of plaques in the arteries, we usually think about the heart or the brain. After all, plaques in the arteries of these organs hinder blood flow and can trigger a heart attack or stroke. But when atherosclerosis is present in these parts of the vascular system, chances are it's lurking throughout, including the peripheral arteries that supply blood to the legs. In this article, Johns Hopkins' cardiologists discuss peripheral arterial disease, a common – but often unrecognized -- form of atherosclerosis.
Called peripheral arterial disease (PAD), this buildup of plaque in the arteries of the legs affects an estimated eight to 12 million Americans -- and up to 20% of those older than age 65. Not surprisingly, PAD is a risk factor for heart attack and stroke. And for some people, the first signs of heart trouble may come from their legs.
But PAD can also cause problems beyond the heart. The lack of blood flow to the legs can make walking difficult. In addition, if PAD becomes severe enough, it can lead to hard-to-heal foot ulcers, infections, or even gangrene in the legs requiring amputation. The good news is that PAD can be diagnosed through simple, noninvasive testing and often managed with lifestyle changes and medication.
How To Recognize PAD -- Your body may give you warning signs that you have PAD -- typically pain in the buttocks or leg muscles, particularly when you are walking or doing other physical activities. The pain usually subsides once you've stopped moving for a few minutes -- a fact that helps differentiate PAD from other causes of leg pain, like spinal stenosis or diabetic nerve damage.
Once PAD progresses, leg pain and cramps may emerge when you're not exercising. You might, for example, feel pain when you are in bed, but find that it goes away if you hang your leg off the bed and let gravity improve blood flow to your extremities. Other potential signs include sores on your feet or lower leg that are slow to heal and bluish or black discoloration of your toes.
Unfortunately, the majority of PAD sufferers have no clear signs, and so the problem often goes unrecognized. That's why it's important to realize that you are at risk for PAD if you already have coronary heart disease (CHD) or have CHD risk factors. As with CHD, the risk factors for PAD include diabetes, smoking, high blood pressure, high cholesterol levels, being overweight, getting little or no exercise, and having a family history of premature cardiovascular disease.
How To Diagnose PAD -- Luckily, a simple test called the ankle-brachial index, or ABI, can be performed during a routine doctor's visit. In an ABI test, your doctor will measure the blood pressure in your arm and in your ankle, and then compare the two measurements. A lower blood pressure in your ankle than in your arm indicates PAD. From there, your doctor may do additional testing to get more information about your condition. For example, you might undergo a treadmill test to see what level of exercise spurs symptoms. In some cases, angiography is used to spot the precise location of the artery blockages. Angiography allows a doctor to visualize blood flow inside the arteries; after injecting contrast dye into your leg arteries, he or she can trace the flow of the dye using x-rays.
The Bottom Line -- If you have potential symptoms of PAD (for example, leg pain while walking or slow healing wounds on your legs and feet), do not pass them off as a natural part of "getting older." Tell your doctor. Getting diagnosed and treated for PAD in its early stages is the best way to prevent this disease from damaging your legs and increasing your risk of heart attack and stroke.
And even if you do not have symptoms but do have risk factors, ask your physician about PAD. Certain high-risk individuals, such as those with diabetes, should be screened for PAD whether or not they have symptoms.
