Introduction to Peripheral Arterial Disease

According to the European Society of Cardiology (ESC), the prevalence of Peripheral Arterial Disease (PAD) often abbreviated now as LEAD (Lower Extremity Artery Disease) is significantly high.

The disease has triggered concern as it is asymptomatic, which means it goes undetected for long periods, increasing the risk for advanced cardiovascular disorders. If caught at the right time, PAD is treatable and can lower the risk of extensive cardiovascular damage.

Hence, it is essential that patients visit a doctor as soon as they see the first sign of the disorder.

In order to ensure that people can identify the signs, we have compiled a brief introduction to what PAD is, its causes, signs and symptoms, and risk factors. 

Peripheral arterial disease (PAD)

Peripheral Arterial Disease or PAD is a circulatory disorder in which peripheral arteries carrying blood to lower limbs are narrowed. This disease is a chronic arterial occlusive disorder that is caused by atherosclerosis in the arteries other than the ones supplying blood to the brain and heart.

Atherosclerosis is a condition in which plaque, which is made up of fat, calcium, fibrous tissue, cholesterols, and other substances, builds up in the arteries. This plaque attaches itself to arterial walls and hardens over time, narrowing the path for the blood flow. This obstruction limits of healthy oxygenated blood to reach organs, limbs, and other parts of the body. Over time, a low level of oxygen triggers other symptoms that can cause other serious problems.

While PAD mostly affects the arteries in the lower extremities, there have been cases where it has affected other parts of the body as well. Since peripheral arteries count for all arteries that carry oxygenated blood away from the heart to the limbs, stomach, head, and kidneys, it can affect them as well.

Lower extremity artery disease (LEAD)

Lower Extremity Artery Disease or LEAD is often used interchangeably with PAD when it affects the arteries of the lower extremities in the body. Everything from the hip to the toes is considered a part of the lower extremities. Blockage in the arteries in this region due to atherosclerosis is defined as LEAD. The term LEAD is now more commonly used among experts in place of PAD, especially when PAD occurs in the lower extremities. 

Symptoms of PAD

It is a known fact that more than 70% of patients suffering from PAD very mild symptoms or are asymptomatic. This means that the patient presents no symptoms at all even when they do have PAD. However, the most common symptom that presents in PAD patients is pain and cramping in the legs while walking, climbing stairs or kind of exercise. This pain is known as claudication

Intermittent claudication

Claudication in PAD patients is not limited to just pain. At times, the pain is accompanied by cramps, numbness, and heaviness felt in the leg muscles. While claudication is usually located in the calf muscles of the affected leg(s), it can also be triggered in the buttocks, thighs, and feet. In PAD patients, these symptoms often ease after resting the leg for some time. They may get triggered again when the affected leg is used to walk or do any other activity. This is called intermittent claudication.

The reason that the leg muscles ache is because they need increased blood flow, especially while they are engaged in an activity. In the unaffected legs, the arteries can increase the blood flow to supply more oxygen to the muscles. However, arteries affected by PAD are narrowed by plaque and unable to increase the blood flow. This lack of oxygen is what triggers the symptoms when the muscles are active. They go away while the leg is in rest as the muscles don’t need as much oxygen. This is mostly the first sign of PAD. The severity of the symptom varies from patient to patient. In some cases, intermittent claudication might mild ache while in other cases it may trigger debilitating pain. 

Other PAD symptoms

 Besides intermittent claudication, other symptoms of PAD include:

  • Sores, ulcers or wounds in the feet
  • A weak or absent pulse in the legs and feet
  • The color of the skin changing to a bluish or pale hue
  • Lower temperature in the affected leg than the unaffected one
  • Shiny and scaly skin on the legs
  • Non-healing wounds on the lower extremities
  • Poor toenail and hair growth on the affected leg
  • Erectile dysfunction in men, especially among those with diabetes

The appearance of these symptoms depends on the severity of PAD. Remember that the majority of PAD patients are asymptomatic and remain so until the disease has progressed. 

Seeing a doctor

People shouldn’t consider leg pain and one of the symptoms mentioned above as a natural part of aging. If a person experiences any of them, it is better he or she goes to a doctor.

A person should see a doctor if he’s asymptomatic but fall in the following categories:

  • Over the age of 65.
  • Under the age of 65 cardiovascular risk factors, such as diabetes, obesity or smoking.
  • Over the age of 50 but have a history of diabetes, obesity or smoking or family history of for LEAD.
  • Under the age of 50 but still have a history of smoking, diabetes, hypertension, high blood pressure or other PAD risk factors.

Along with these people, there is another group of patients that are under a real threat for PAD. This group of patients includes those asymptomatic patients that may have a severe level of disease not be presenting an inability to move. This particular group is referred to as ‘masked LEAD.’ 

Causes and risk factors

As explained earlier, PAD is caused by atherosclerosis, which is also to as Arteriosclerosis. This disease is characterized by the narrowing of arteries due to plaque build-up in the arterial walls. What causes this plaque to build up is not known. Other than atherosclerosis, some less commonly known causes of PAD include blood vessel inflammation, abnormalities in the muscles or ligaments, exposure to radiation or injury to the lower extremities. 

Risk factors

Some risk factors that might increase the chances of someone developing PAD include:

  • Aging
  • Smoking
  • Diabetes
  • High Blood Pressure
  • High Cholesterol
  • Obesity
  • A family history of PAD or cardiovascular diseases
  • High Levels of Homocysteine

Detecting PAD

The best way to detect PAD is through the measurement of the Ankle-Brachial Index. Measuring ABI involves dividing the ratio of blood pressure from both ankles with the blood pressure taken from the upper arm. This is an easy and non-invasive detection technique that can help in early diagnosis of PAD.

Read an article on How Exercise Can Help in Peripheral Artery Disease by Lisa Esposito of U.S. News.