By James B. Williams, MD
Peripheral arterial disease (PAD) is a term used to classify disease in the peripheral arteries, most commonly the arteries in the pelvis and legs. Simply stated, PAD is the buildup of plaque in the walls of arteries, which reduces or blocks the flow of blood through the legs. If blood flow is blocked to a part of the leg, then tissue beyond that point can begin to die because it is not being nourished with oxygenated blood. This can produce symptoms of pain in the legs, sores that do not heal, or toes that blacken — all of which, in advanced stages, can lead to amputation of a limb. Often, people with PAD do not experience any symptoms, and this makes it difficult to know there is a health concern that should be addressed.
PAD is progressive and incurable, affecting an estimated 8 to 12 million people in the U.S. alone. Interestingly, PAD affects the same number of Americans as cancer (11 million), but mortality rates associated with PAD are higher. Even though PAD is more prevalent than cancer in the U.S., only 20 to 30 percent of individuals with PAD receive treatment.
Risk factors
There are a number of risk factors associated with PAD; some of which are controllable. Key risk factors for PAD are listed below; smoking and diabetes top the list.
- Smoking: Smoking is the single most important, controllable risk factor for PAD. Smoking introduces high levels of lead and calcium into the body, which increases the risk of PAD. More than 80 percent of patients with PAD are current or former smokers. In smokers, PAD develops 10 years earlier, it is more likely to progress, and it doubles the risk of amputation.
- Diabetes: People with diabetes are two to four times more likely to develop PAD than non-diabetics, especially if they are over the age of 50. PAD is more severe and progresses more rapidly in diabetic patients; the risk increases in proportion to the severity of diabetes and its duration. With diabetes, nerves become impaired from increased blood sugar levels or a lack of receiving oxygenated blood, causing a condition called neuropathy. Patients with neuropathy have decreased sensation in their feet and legs, and their body has a more difficult time healing from injury and fighting infection. Therefore, diabetic PAD patients have a higher risk of amputation.
- Advancing age: The risk of PAD increases dramatically with age. Up to 20 percent of people 65+ years of age have PAD. Further, those 50+ years of age who also have risk factors for cardiovascular disease (e.g., high blood pressure or diabetes) — and people who smoke — are all more susceptible to PAD.
- High cholesterol: Excess cholesterol and fat in the blood contribute to the formation of plaque in the arteries. When this happens, there is reduced or blocked blood flow to the heart, brain, or limbs, which can lead to cardiovascular disease.
- History of cardiovascular disease: People with heart disease have a one in three chance of having PAD. PAD corresponds with a 40 percent increased risk of stroke, a 20 to 60 percent increased risk of heart attack, and an increased risk of death due to coronary events. Up to 80 percent of PAD patients die of cardiovascular causes. For these reasons, early treatment of the disease is critical.
- High blood pressure: Elevated blood pressure raises the risk of developing plaque in the arteries; it is important to manage high blood pressure to decrease the risk of PAD and other cardiovascular diseases.
- Ethnicity: Some ethnic groups (e.g., African-Americans, Hispanics) are more than twice as likely to have PAD.
Symptoms
The most common symptom associated with PAD is claudication — pain or cramping in the buttocks, legs, or feet — that is noticeable during activities such as walking or climbing stairs. Other common symptoms of PAD include leg pain at rest, impaired walking, wounds or sores that do not heal on the legs or feet, color changes (paleness, blueness) in the skin of the feet, lower temperature in one leg compared with the other, poor toenail growth, and/or decreased hair growth on the toes and legs.
In more than half of cases, an individual with progressing PAD will not have typical signs or symptoms, but that does not mean they should not talk with their physician or be treated. Early treatment of PAD is key to managing the disease long term. Diagnosing PAD can be done quickly and noninvasively in a physician’s office. Oftentimes, it is as simple as checking the feet for signs of PAD.
Diagnosis
People at risk for PAD should talk with their physician to see if they should undergo testing to determine the presence of PAD. During this visit, the physician will take a medical and family history, will perform a physical, and may conduct a simple diagnostic test. During the physical exam, the health care provider may check pulses in the legs and feet; look at the color, temperature, and appearance of the legs and feet; and look for sores that are not healing on the legs and feet.
- Ankle-brachial index: A health care provider may perform a simple, noninvasive test called an ankle-brachial index (ABI) test. Painless and quick, the ABI compares the blood pressure readings in the ankles with those in the arms. This test can determine whether someone has PAD, but it cannot identify which arteries are affected.
- Doppler ultrasound: Doppler ultrasound testing uses sound waves to measure the blood flow through the leg and may be used to determine if a specific artery is open or blocked. The test is painless and does not require the use of needles, dye, or X-ray. Patients with documented PAD are referred to a specialist for treatment.
- Angiography/Fluoroscopy: Angiography is a minimally invasive test that uses X-ray imaging to show exactly where in a vessel blockage is located and the extent of disease. During this procedure, a small tube (catheter) is inserted into an artery in the groin or arm and contrast dye is injected through the catheter. Then, images of the vessels are projected onto a screen for viewing; this helps to determine exactly where blockages occur and then helps to guide treatment.
Treatment
There are three main approaches to treating PAD: lifestyle changes, medication to control things like high blood pressure or high cholesterol, and minimally invasive (endovascular) procedures or surgery. Early diagnosis and treatment will ensure treatment options are broadest and can reduce the risk of developing critical limb ischemia or undergoing more invasive treatments, including amputation.
Minimally invasive treatment options for PAD include atherectomy, angioplasty, and stenting — all of which restore blood flow through a narrowed artery, either by removing the plaque or displacing it. More severe cases of PAD may require a surgical procedure to bypass the blocked artery.
Untreated PAD, or diagnosing the disease too late in its progression, may lead to removing a diseased portion of the leg or foot. In some cases, amputation is necessary. However, up to 85 percent of amputations are preventable, if the disease is diagnosed early and treated through a minimally invasive procedure.
For information, contact the Cardiac Thoracic & Endovascular Therapies, S.C., at 309-680-5000. Dr. Williams is board-certified in three surgical specialists: cardiothoracic, vascular, and general. “Easy in, Easy Out” service advantages. Visit www.cvendo.com. Located at 2420 W. Nebraska Avenue, Peoria, IL.
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