Medical Spotlight: What Is Peripheral Arterial Disease?
Peripheral Artery Disease (PAD) is a condition characterized by poor blood circulation due to the narrowing of the arteries in the arms, legs, and internal organs. It’s often caused by atherosclerosis, which is the buildup of fat and cholesterol – called plaque – in the arteries. This plaque causes the arteries to become partially blocked. The result is a limited blood supply to the tissues, which eventually causes tissue death, necessitating lower limb amputation.
What Causes Peripheral Arterial Disease?
Approximately 8.5 million people in the United States have peripheral artery disease. Worse yet, the condition is more common in Blacks than in other racial groups with men more likely than women to develop PAD.
The most common cause of PAD is atherosclerosis, a condition in which plaque builds up in the artery walls and reduces blood flow. Less common causes include blood vessel inflammation, radiation exposure, unusual anatomy of the muscles or ligaments, and injury to the limbs.
If your peripheral arterial disease is caused by fat buildup in the arteries, then you may also be at risk of developing critical limb ischemia (CLI). CLI begins as open non-healing wounds, an injury, or infection to the feet or legs. If left untreated, this condition causes tissue death, sometimes requiring amputation of the affected limb.
Symptoms of PAD
PAD patients usually start with mild symptoms or no symptoms at all. 50% of people living with PAD in the US have no symptoms. However, common symptoms of PAD include:
- Muscle cramps in the calf area when walking
- Pain in the limbs while walking that feels better after resting
- Advanced ulceration or gangrene
- Weak or absent pulses in the legs or feet
- A lower temperature in one leg than the other
- Skin discoloration
Risk Factors for PAD
Certain risk factors can increase the chances of developing severe conditions. They include:
- Medical conditions such as high cholesterol, high blood pressure, and diabetes – An estimated 1 out of every 3 people with diabetes and aged over 50 years has PAD, making it a primary co-morbidity of diabetes
- Smoking – The most important thing patients can do to prevent or slow down PAD is to avoid the use of tobacco products
- Excessive levels of c-reactive or homocysteine
Diagnosis of PAD
Anyone exhibiting the symptoms of PAD or at risk of developing the disease should go for screening to rule out all other conditions. Diagnosing PAD in a patient with a non-healing wound is also important.
Non-healing wounds are almost always accompanied by pain, swelling, and redness. If left untreated, these ulcers could get infected, causing long-term health complications, including lower limb amputation.
A physical exam is first done to identify signs of PAD. The doctor will check for abnormal pulses or poor wound healing in the area with restricted blood flow. He or she may also use a stethoscope to determine whether there are any whooshing sounds over your arteries.
An ankle-brachial index (ABI) test is the most commonly used measurement for the detection of PAD in clinical settings. In an ABI test, blood pressure cuffs are placed around the upper arms and ankles.
A special ultrasound device is then used to evaluate blood pressure and flow in the limbs. It compares the blood pressure in your ankle to that in your arm to develop an ABI calculation. An ABI of 1.0 to 1.3 is in the normal range and any value above or below this range is considered abnormal. Other diagnostic tests may include basic blood work, biopsy, and non-invasive studies.
Treatment and Interventions for PAD
Since PAD is a manifestation of systemic atherosclerosis in the lower limbs, treatment and intervention focus on reducing the risk of heart attack and stroke, and improving quality of life by easing the pain that occurs while walking.
The American College of Cardiology Foundation and the American Heart Foundation (ACCF/AHA) published a document outlining some of the steps to take in the treatment of patients with PAD. They recommend:
Initial treatment of PAD involves making some lifestyle changes to reduce the risk factors. These include exercising, quitting tobacco products, practicing good foot care, and eating a balanced diet that is high in fiber and low in cholesterol, fat, and sodium.
Medicine can help with conditions such as high blood pressure, diabetes, and high cholesterol. An antiplatelet medication such as aspirin may help reduce the risk of heart attack and stroke. The doctor can prescribe cilostazol to improve your walking distance. This drug especially enables patients with intermittent claudication to exercise longer before experiencing leg pain.
Endovascular (Minimally Invasive) or Surgical Treatments
More advanced PAD may require minimally invasive or surgical treatment such as balloon angioplasty, bypass surgery, or atherectomy. In an angioplasty, a long, thin catheter is put into a blood vessel and guided to the blocked artery with the help of an x-ray. A balloon is then inflated to press the plaque or blood clot against the side of the artery, thus widening the artery and allowing for increased blood flow.
A peripheral artery bypass surgery is often done to heal foot sores caused by poor blood circulation. A vein or synthetic graft is attached above or below the blockage to reroute blood flow, thus increasing circulation to the legs and feet. In atherectomy, a vascular surgeon uses a catheter to remove fat buildup in the arteries.
If you have peripheral artery disease, you’ll likely live with it for the rest of your life. While there’s no cure for this condition, it is manageable. Being aware of the risk factors for PAD may motivate you to take action to prevent the development of PAD. You should discuss your risk factors for PAD with your healthcare provider and report any symptoms you’re having, such as pain, weakness, or numbness in your legs.