Peripheral Artery Disease (PAD)

What happens in PAD

Atherosclerosis is the gradual buildup of cholesterol, calcium and inflammatory cells in artery walls. In PAD it narrows the arteries to the legs, such as the iliac, femoral and popliteal arteries. At rest, enough blood gets through. During walking, muscles need more oxygen, and the narrowed arteries cannot keep up, causing pain. In severe disease, blood flow is too low even at rest.

PAD and coronary artery disease share the same cause. People with PAD have a much higher risk of heart attack and stroke, so treatment protects the whole body, not just the legs.

Symptoms

Intermittent claudication

• cramping, aching, tiredness or heaviness (leg pain) in the calf, thigh or buttock during walking or climbing stairs
• comes on after a predictable distance
• eases within about 10 minutes of stopping, without needing to sit or change position

Other signs

• coldness of the lower leg or foot, especially compared with the other side
• weak or absent pulses in the legs and feet
• shiny, thin, hairless skin on the legs
• slow-growing toenails
• color changes: pale when raised, red or purple when hanging down
• sores on the feet or toes that heal slowly (arterial ulcers)
• erectile dysfunction in men

Many people with PAD, especially those with diabetes, have no symptoms or atypical leg discomfort.

Critical limb-threatening ischemia

Critical limb ischemia is advanced PAD with:

• pain in the foot or toes at rest, often at night, relieved by hanging the leg down
• non-healing ulcers
• gangrene (dead, blackened tissue)

It needs urgent treatment to prevent amputation.

Claudication vs other causes of leg pain

Risk factors

• smoking: the strongest risk factor
• type 2 diabetes
• high blood pressure and high cholesterol
• age over 65, or over 50 with other risk factors
• chronic kidney disease
• family history of atherosclerosis
• Black Americans are at higher risk

Diagnosis

• examination: pulses in the legs and feet, skin, hair and wounds
• ankle-brachial index (ABI): compares blood pressure at the ankle with blood pressure at the arm using a cuff and Doppler probe. A normal ABI is 1.00 to 1.40. An ABI of 0.90 or less indicates PAD. Above 1.40 suggests stiff, calcified arteries and needs other tests
• exercise ABI: if symptoms suggest PAD but the resting ABI is normal
• toe pressures in people with calcified arteries, common in diabetes and kidney disease
• duplex ultrasound: shows narrowed areas
• CT or MR angiography, or catheter angiography, before procedures

Treatment

Lifestyle

• stop smoking: the single most important step. Ask about medicines and support
• supervised exercise therapy: walking until moderate pain, resting, then repeating, for 30 to 45 minutes, at least 3 times a week for 12 weeks. This can significantly increase pain-free walking distance
• healthy diet and weight management
• foot care: check your feet daily, wear well-fitting shoes, and see a podiatrist for nails and calluses, especially with diabetes

Medicines

• statins: lower cholesterol and reduce heart attack, stroke and limb risk
• antiplatelet medicines: aspirin or clopidogrel to prevent clots
• low-dose rivaroxaban with aspirin for some people at high risk
• blood pressure and diabetes control
• cilostazol: can improve walking distance in claudication (not for people with heart failure)

Procedures

When symptoms remain limiting despite exercise and medicines, or in critical limb ischemia:

• endovascular treatment: balloon angioplasty, stents or atherectomy through a catheter
• bypass surgery: rerouting blood around a blocked artery using a vein or graft
• amputation: a last resort for gangrene or non-healing wounds

Complications

• heart attack and stroke
• non-healing wounds and infections
• gangrene and amputation
• acute limb ischemia from a sudden clot

PAD vs PVD

Peripheral vascular disease (PVD) is a broader term that includes problems with veins, such as varicose veins, and lymph vessels. PAD refers specifically to arteries. The two terms are sometimes used interchangeably.

Frequently asked questions

What are the first signs of peripheral artery disease?

The most common early sign is cramping, aching or tiredness in the calf, thigh or buttock when walking that eases within minutes of rest. Other signs are cold feet, weak foot pulses, shiny hairless skin on the legs and slow-healing foot sores. Many people have no symptoms at first.

Can peripheral artery disease be reversed?

The plaque usually cannot be fully removed, but PAD can be stabilized and symptoms improved. Stopping smoking, supervised walking, statins and antiplatelet medicines slow progression. Procedures can restore blood flow when needed.

Is walking good for PAD?

Yes. Structured walking exercise is one of the most effective treatments for claudication. Walking until moderate discomfort, resting, and repeating for 30 to 45 minutes several times a week helps the body build new small blood vessels and improves walking distance.

How is PAD diagnosed?

The main test is the ankle-brachial index, comparing blood pressure in your ankles and arms. An ABI of 0.90 or lower indicates PAD. Ultrasound and angiography show where arteries are narrowed.

Is PAD a sign of heart disease?

Often. PAD is caused by the same process as coronary artery disease, and people with PAD have a much higher risk of heart attack and stroke. Treatment focuses on protecting the heart and brain as well as the legs.