ConditionHeart & circulation
Peripheral Arterial Disease: Stages, Complications and Treatment
Peripheral arterial disease (PAD), also called peripheral vascular disease, is narrowing or blockage of the arteries that carry blood to the legs, and less often the arms, usually from atherosclerosis. It progresses through stages, from no symptoms, to calf pain when walking, to pain at rest and wounds that will not heal. Smoking and diabetes are the strongest risk factors. Walking therapy, stopping smoking and medicines are the foundation of treatment, with angioplasty or bypass when blood flow is severely reduced.
Also called: PAD, peripheral vascular disease (PVD), lower extremity arterial disease, arterial insufficiency of the legs
At a glance
- What it is
- Narrowed limb arteries, mostly in the legs, from plaque build-up.
- Who gets it
- Over 6 million US adults over 40; risk rises steeply with smoking, diabetes and age.
- Stages
- Silent disease, claudication (pain on walking), rest pain, and tissue loss (ulcers or gangrene).
- Test
- Ankle-brachial index (ABI), comparing ankle and arm blood pressure.
- Treatment
- Stop smoking, supervised walking, statins, antiplatelets, and revascularization when needed.
When to get help
Call 911 or go to the ER
- A leg or foot that suddenly becomes cold, pale, painful, numb or weak (acute limb ischemia): call 911 or your local emergency number
- Black or dark skin on the toes or foot with spreading redness, fever or a foul smell
- Chest pain, or sudden face droop, arm weakness or speech difficulty
See a doctor within a day or two
- Burning pain in the foot or toes at rest, especially at night, eased by hanging the leg over the bed
- A sore on the foot or toes that has not started healing within 2 weeks
- Any wound on the foot of someone with diabetes and PAD
Book a routine appointment
- Cramping pain in the calf, thigh or buttock with walking that eases within minutes of rest
- Cold feet, shiny hairless skin on the shins, slow-growing toenails or weak foot pulses
- Erectile dysfunction with leg pain on walking
- Age over 65, or over 50 with smoking or diabetes, and no PAD check
How PAD progresses
PAD is usually caused by atherosclerosis: plaque in the artery walls narrows the vessel. At rest, the legs may receive enough blood, but during walking the muscles need more than the narrowed arteries can supply, causing pain. As blockages worsen, even resting blood flow becomes inadequate.
Stages of PAD
| Stage | Features |
|---|---|
| Asymptomatic | Abnormal ABI but no symptoms; up to half of people with PAD |
| Claudication | Pain, cramping or fatigue in the calf, thigh or buttock with walking, relieved by rest |
| Rest pain | Burning foot pain at rest, often at night, eased by dangling the leg |
| Tissue loss | Non-healing ulcers or gangrene on the toes or foot |
Rest pain and tissue loss are called chronic limb-threatening ischemia (critical limb ischemia), which carries a high risk of amputation without treatment.
The basic picture of PAD, including claudication, is also described on our peripheral artery disease page.
Risk factors
- smoking: the strongest risk factor; current smokers have several times the risk
- diabetes: linked to more severe, below-the-knee disease and foot ulcers
- age over 65
- high blood pressure and high cholesterol
- chronic kidney disease
- family history of vascular disease
- Black Americans have a higher prevalence
Signs a doctor looks for
- weak or absent pulses in the feet or behind the knees
- cool skin, pale feet when raised and dusky red when hanging down
- shiny, thin, hairless skin on the lower legs
- thickened, slow-growing toenails
- slow-healing sores on toes, heels or pressure points
- muscle wasting in the calf
Diagnosis
- Ankle-brachial index (ABI): blood pressure at the ankle divided by blood pressure in the arm. Normal is 1.00 to 1.40; 0.90 or below indicates PAD. Values above 1.40 mean the arteries are stiff and calcified (common in diabetes and kidney disease), and a toe-brachial index is used instead.
- Exercise ABI: when symptoms suggest PAD but resting ABI is normal.
- Duplex ultrasound: shows the location and severity of narrowing.
- CT or MR angiography and catheter angiography: to plan procedures.
- Toe pressures and transcutaneous oxygen in people with wounds, to predict healing.
Treatment
Protecting the heart and brain
PAD is a sign of widespread atherosclerosis. People with PAD have a high risk of heart attack and stroke, so treatment includes:
- stopping smoking completely, with medicines and support
- high-intensity statins
- antiplatelet therapy (aspirin or clopidogrel); low-dose rivaroxaban with aspirin for selected patients
- control of blood pressure and diabetes, including SGLT2 inhibitors or GLP-1 receptor agonists where appropriate
Improving walking
- Supervised exercise therapy: walking to moderate pain, resting, and repeating, for 30 to 45 minutes, at least 3 times a week for 12 weeks. It can roughly double walking distance.
- Home-based walking programs are an alternative.
- Cilostazol can improve walking distance in some people (not used in heart failure).
Revascularization
- Endovascular procedures: balloon angioplasty, stents and atherectomy through a catheter
- Bypass surgery: using a vein or synthetic graft to route blood around blockages
- These are used for chronic limb-threatening ischemia, and for claudication that remains disabling despite exercise and medicines.
Foot care
- check feet daily, especially with diabetes
- keep skin moisturized and toenails trimmed carefully
- wear well-fitting shoes and never walk barefoot
- seek care early for any wound
- see a podiatrist regularly
Complications
- heart attack and stroke
- non-healing wounds and infections
- gangrene and amputation
- acute limb ischemia from a sudden clot
Outlook
Most people with claudication remain stable over years, and only a minority progress to limb-threatening disease, especially if they stop smoking and exercise. The bigger risk is cardiovascular events, which aggressive risk factor treatment greatly reduces.
Frequently asked questions
What are the stages of peripheral arterial disease?
PAD progresses from no symptoms, to claudication (leg pain with walking that eases with rest), to rest pain in the foot, and finally to tissue loss with ulcers or gangrene. The last two stages are called chronic limb-threatening ischemia.
Is peripheral arterial disease the same as peripheral vascular disease?
The terms are often used interchangeably for narrowed leg arteries. Strictly, peripheral vascular disease can include vein problems too, while peripheral arterial disease refers only to arteries.
Can you reverse peripheral arterial disease?
Plaque usually cannot be fully removed, but stopping smoking, regular walking and statins can stabilize disease and greatly improve walking distance. Angioplasty, stents or bypass can restore blood flow when blockages are severe.
What is a normal ankle-brachial index?
A normal ABI is between 1.00 and 1.40. A value of 0.90 or less means PAD. Values between 0.91 and 0.99 are borderline. Above 1.40 suggests stiff, calcified arteries that make the test unreliable.
What happens if PAD is left untreated?
Untreated PAD increases the risk of heart attack, stroke and death. In some people, leg blood flow worsens to cause pain at rest, wounds that will not heal, gangrene and amputation. Treatment substantially reduces these risks.
Sources
This guide was written from current patient and clinical guidance, including:
- American Heart Association/American College of Cardiology: 2024 Guideline for the management of lower extremity peripheral artery disease
- Society for Vascular Surgery: Global vascular guidelines on chronic limb-threatening ischemia
- National Heart, Lung, and Blood Institute: Peripheral artery disease
- CDC: Peripheral arterial disease
- MedlinePlus: Peripheral artery disease - legs