What is Peripheral Artery Disease?

Peripheral arterial disease (PAD) is a condition that affects the arteries outside of the heart and brain, most commonly those supplying blood to the legs and feet. It is also referred to as peripheral vascular disease. Patients diagnosed with PAD experience decreased blood flow in their lower extremities, commonly known as "poor circulation." In most cases, the narrowing of arterial flow due to atherosclerotic plaques restricts blood flow to the distal parts of the body. This reduced blood flow can lead to pain in the thighs or calves while walking, as the leg muscles experience temporary ischemia or lack of blood supply during exertion. This walking-induced pain is termed intermittent claudication, which essentially means "limping." Some PAD patients face a critical reduction in blood flow, necessitating urgent surgical intervention.⁴ Even in asymptomatic patients, diagnosing PAD holds significant clinical importance because it serves as an indicator of systemic atherosclerosis. Patients with PAD face an equivalent cardiovascular risk to individuals who have experienced a heart attack, emphasizing the need for management of risk factors to improve long-term survival.¹

Stages 

Two classification systems, the Fontaine and Rutherford classifications, are used to assess the severity of peripheral arterial disease (PAD) based on clinical symptoms.² The Fontaine classification includes five stages: 

• Stage I indicates no symptoms 
• Stage IIa represents mild intermittent claudication or limping with a walking distance of over 200 meters
• Stage IIb denotes moderate to severe claudication with a walking distance of less than 200 meters 
• Stage III signifies leg pain even during rest 
• Stage IV indicates necrosis or gangrene

The Rutherford classification consists of six stages: 

• Stage 0 for silent cases
• Stage 1 for mild claudication
• Stage 2 for moderate claudication 
• Stage 3 for severe claudication 
• Stage 4 for leg pain even during rest
• Stage 5 for ischemic ulcers not exceeding the digits of the foot
• Stage 6 for severe ischemic ulcers or gangrene

Causes 

Peripheral artery disease typically arises from atherosclerosis, although it can also comes from blood vessel inflammation, injury, or exposure to radiation. The risk factors associated with this condition include diabetes, smoking, obesity (with a body mass index over 30), high blood pressure, high cholesterol, advancing age (especially over 50), a family history of peripheral artery disease, heart disease, or stroke, as well as elevated levels of homocysteine, a protein involved in tissue maintenance and development.¹

Signs and symptoms

The reduced blood flow to the limbs can result in various symptoms, including:

• Claudication: This refers to cramping, pain, or fatigue in the legs or buttocks during physical activity, which typically improves with rest
• Numbness or weakness: Some individuals may experience numbness, weakness, or a feeling of coldness in the lower extremities
• Slow healing of wounds: Decreased blood flow can impair the healing process, leading to slow or non-healing wounds, especially in the feet
• Changes in skin appearance: PAD may cause the skin on the legs or feet to become pale, shiny, or discolored. Hair loss and weak or absent pulses in the affected areas are also common¹

Diagnosis

Diagnosis involves assessing the patient's history and conducting an ankle-brachial index (ABI) test, a useful tool that compares blood pressure at the ankle to that in the arm: an ABI below 0.9 indicates PAD. Doppler studies, CT angiography, MRA ( Magnetic Resonance Angiography), transcutaneous oximetry, and Electrocardiogram (ECG) may also be utilized to assess blood flow and occlusion sites. Physical exam may show reducedpulses, pain, pallor, muscle atrophy, and cool skin.¹

Management

The management of peripheral arterial disease (PAD) aims to achieve two main goals: lowering cardiovascular risk and improving walking ability. All patients with PAD, regardless of symptoms, are at increased risk of cardiovascular events and should make lifestyle changes to lower their cardiovascular risk profile.¹

This includes:

• Quitting smoking
• Controlling high blood pressure
• Managing cholesterol levels
• Addressing diabetes

Treatment options for improving walking ability depend on the patient's symptoms and disease severity include:

• Supervised exercise programs
• Medications such as cilostazol and pentoxifylline can be used to treat claudication, with cilostazol promoting vasodilation and pentoxifylline improving oxygen delivery. 
• Endovascular treatments like balloon angioplasty and stent placement are minimally invasive options for non-responsive cases. 
• Surgery, such as bypass grafts or endarterectomy, is reserved for selected patients with significant symptoms
• The use of cholesterol-lowering drugsis well-supported to improve atherosclerotic disease, but lifestyle changes and risk factor reduction are also essential¹

Risk factors

Risk factors for peripheral arterial disease include smoking, diabetes, high blood pressure, high cholesterol, obesity, older age, a family history of PAD, and a sedentary lifestyle. Diagnosis of PAD typically involves a physical examination, medical history assessment, and various tests such as ankle-brachial index (ABI), Doppler ultrasound, or angiography.¹

Complications

If left untreated, PAD can lead to more severe complications, such as critical limb ischemia, where blood flow to the affected limb is severely restricted. This can result in tissue damage, non-healing ulcers, infections, and even gangrene, increasing the risk of limb amputation. Additionally, PAD is often associated with an increased risk of cardiovascular events, such as heart attack and stroke.¹

FAQs

How can I prevent peripheral artery disease?

• Get plenty of physical activity to help prevent PAD or improve symptoms of PAD
• Do not use tobacco as smoking increases the risk of PAD and makes PAD symptoms worse
• Control high blood pressure and manage high blood cholesterol and diabetes

If you have PAD, participating in supervised exercise training programs can improve and prolong your ability to walk longer distances.³

How common is peripheral artery disease?

PAD affects over 200 million adults worldwide, with a prevalence of up to 20% in those over 70. It is equally commonin older people whether they are AMAB or AFAB. Smoking increases the risk of PAD fourtimesand worsens disease severity, leading to shorter life spans and higher rates of limb ischemia and amputation.¹

When should I see a doctor?

You should consider seeing a doctor if you experience any signs or symptoms of peripheral arterial disease (PAD). 

These may include:

• Leg pain or discomfort
• Slow healing of wounds or sores
• Changes in skin color or temperature.
• Weak or absent pulses
• Erectile dysfunction

Summary

Peripheral arterial disease (PAD) is a condition that affects the arteries outside of the heart and brain, most commonly those supplying blood to the legs and feet. It is characterized by decreased blood flow, resulting in symptoms such as leg pain, slow wound healing, and changes in skin appearance. PAD is typically caused by atherosclerosis and is associated with risk factors like smoking, diabetes, high blood pressure, and high cholesterol. Diagnosis involves assessing medical history and conducting tests like ankle-brachial index (ABI) measurements and imaging studies.

Management strategies for PAD focus on lowering cardiovascular risk and improving walking ability. Lifestyle changes such as quitting smoking, controlling high blood pressure, and managing cholesterol and diabetes are important. Treatment options include supervised exercise programs, medications like cilostazol and pentoxifylline, endovascular interventions like angioplasty and stent placement, and surgery for selected cases. Cholesterol lowering drugsmay be prescribed to improve atherosclerotic disease. If left untreated, PAD can lead to complications like critical limb ischemia and an increased risk of cardiovascular events.