Vascular Surgery

Peripheral Arterial Disease

Peripheral arterial disease (PAD) is a manifestation of systemic atherosclerosis in which lower-limb arterial flow cannot meet demand, causing intermittent claudication or, when tissue perfusion is inadequate at rest, chronic limb-threatening ischaemia.

Definition

Peripheral arterial disease is atherosclerotic narrowing or occlusion of arteries supplying the limbs, most often the legs. It ranges from asymptomatic disease and intermittent claudication to chronic limb-threatening ischaemia with rest pain, ulceration or gangrene.

Epidemiology

PAD is more common with increasing age, smoking, diabetes, hypertension, dyslipidaemia, chronic kidney disease and other atherosclerotic disease. It is a marker of systemic cardiovascular risk, so myocardial infarction and stroke prevention are central to care even when leg symptoms are mild.

Pathophysiology

Atherosclerotic plaque reduces arterial lumen and flow reserve. Exercise raises muscle demand beyond the available supply, producing claudication. Further loss of perfusion causes rest pain, poor wound healing, ulceration and gangrene. Diabetes and chronic kidney disease can cause arterial calcification and make ABPI falsely high or non-diagnostic.

First principles

Claudication is a supply-demand problem

Atherosclerotic narrowing limits the maximum blood flow available to exercising muscle. Resting demand may still be met, but walking increases demand beyond supply and produces reproducible muscle pain that settles with rest. The distance is often consistent enough to be a useful clinical clue, but symptoms and walking ability vary with terrain, pace and comorbidity.^1,2,3

Tissue loss means resting perfusion is failing

When perfusion becomes inadequate even at rest, the person may develop chronic limb-threatening ischaemia (CLTI), previously described in NICE guidance as critical limb ischaemia. Rest pain, non-healing ulceration or gangrene needs urgent vascular assessment because the goals shift from symptom control to pain relief, wound preservation, limb salvage and safe revascularisation.^1,2

PAD is a systemic cardiovascular-risk marker

Atherosclerosis in the leg commonly coexists with coronary and cerebrovascular disease. Treating the leg symptom alone is not enough: smoking cessation, antiplatelet treatment where indicated, lipid modification, blood-pressure and diabetes management, exercise and shared risk-factor care reduce future cardiovascular harm.^1,4,3

Severity and urgency are clinical, not ABPI-only decisions

History, foot examination, pulses, Doppler signals, tissue loss, pain and function determine severity. ABPI supports diagnosis, but a normal or raised ABPI does not exclude PAD in diabetes because arterial calcification can make vessels incompressible. A sudden deterioration is acute limb ischaemia, not simply progression of stable PAD, and requires the emergency vascular pathway.^1,5,6

Presentation

Intermittent claudication is exertional leg-muscle pain, usually in the calf, thigh or buttock, that is reproducible and relieved by rest. Advanced disease causes forefoot rest pain, non-healing ulcers or gangrene. Sudden pain, pallor, coldness, sensory loss or weakness suggests acute limb ischaemia and needs a separate emergency pathway.^1,2,6,3

Cardinal features

Exertional calf, thigh or buttock pain relieved by rest
Reduced or absent femoral, popliteal or foot pulses
Cool, shiny skin with hair loss or brittle nails
Dependent rubor or prolonged capillary refill
Forefoot rest pain, often worse when the leg is elevated at night and eased by dependency
Painful non-healing ulceration or gangrene at a distal pressure point

Red flags

Rest pain, ulceration or gangrene: urgent vascular referral for possible CLTI
Rapidly worsening pain, pallor, coldness, paraesthesia or weakness: suspect acute limb ischaemia
Spreading infection in an ischaemic foot or systemic illness: urgent multidisciplinary assessment
A non-healing foot wound in diabetes, even if ABPI is normal or raised
Disabling symptoms despite risk-factor treatment and supervised exercise
New chest pain, transient neurological symptoms or stroke symptoms indicating associated cardiovascular disease

Investigations

Clinical vascular assessment and ABPI

Take a structured history of exertional distance, rest pain, tissue loss and acute change. Examine both limbs and feet, palpate femoral, popliteal and pedal pulses, and measure ABPI at rest with a Doppler where possible. Calculate the highest ankle pressure divided by the highest arm pressure for each leg.

Expected finding: An ABPI below 0.9 supports PAD. A normal or raised result does not exclude PAD in diabetes or incompressible arteries; interpret alongside symptoms, examination and Doppler signals.

^1,2,6

Duplex ultrasound when revascularisation is being considered

Offer duplex ultrasound as first-line anatomical imaging when revascularisation is being considered. It localises stenosis or occlusion and assesses flow without ionising radiation.

Expected finding: Flow-limiting stenosis or occlusion with altered velocities and distal run-off that helps plan intervention.

^1,2

Contrast-enhanced MRA or CTA for treatment planning

If further imaging is needed after duplex, offer contrast-enhanced MRA. Offer CTA when MRA is contraindicated or not tolerated, considering renal function, contrast risk and the need for detailed arterial anatomy.

Expected finding: The level, length and distribution of disease, distal run-off and anatomy relevant to angioplasty or bypass.

Cardiovascular and tissue-risk assessment

Assess smoking, blood pressure, diabetes, lipids, renal function, cardiovascular symptoms, mobility, nutrition, wound status and infection. In CLTI, document pain, tissue loss, infection and function so a vascular multidisciplinary team can plan limb salvage or palliation.

Expected finding: Modifiable cardiovascular risks, tissue loss or infection requiring parallel medical, wound, podiatry, diabetes, pain or vascular management.

^1,4,2

Management

Step	Detail	Source
Start best medical therapy and secondary cardiovascular prevention	Offer smoking-cessation support and manage blood pressure, diabetes, lipids, diet, weight and exercise. Offer antiplatelet treatment and lipid modification in line with current NICE guidance and the person's indications, comorbidities and preferences; use current BNF and local formulary information for medicine selection and doses. Do not treat PAD as a local leg problem only.^1,4,3	NICE CG147, NICE NG238 and NHS PAD treatment information
Offer a supervised exercise programme for intermittent claudication	Offer supervised exercise to everyone with intermittent claudication. A typical NICE-supported programme involves about 2 hours of supervised exercise each week for 3 months, encouraging walking towards maximal tolerable pain with rest intervals, provided there is no contraindication. Reinforce that regular activity is needed to maintain benefit.^1,7,3	NICE CG147 recommendations 1.5.1 and 1.5.2; NHS PAD treatment information
Consider revascularisation for persistent lifestyle-limiting claudication	Consider angioplasty when risk-factor advice has been reinforced, supervised exercise has not produced satisfactory improvement and imaging confirms suitability. Consider bypass when symptoms remain severe and angioplasty is unsuitable or unsuccessful, after discussion of procedural risks, durability, anatomy, vein availability and patient preference. Do not offer invasive treatment solely because an arterial narrowing appears on imaging without clinically important symptoms.^1,2	NICE CG147 recommendations 1.5.3 to 1.5.8
Refer chronic limb-threatening ischaemia urgently to a vascular multidisciplinary team	Rest pain, tissue loss or gangrene requires urgent vascular assessment. The vascular multidisciplinary team should consider revascularisation, wound and infection care, analgesia, off-loading, diabetes and renal issues, functional status and patient preference. Angioplasty or bypass may be appropriate; the current NICE recommendations are under update for drug-eluting stents and drug-coated balloons in femoropopliteal CLTI, so do not hard-code a device choice into general teaching.^1,5,2	NICE CG147 and April 2026 exceptional surveillance of CG147
Manage ischaemic pain, wounds and infection in parallel	Offer analgesia appropriate to severity and current medicines guidance, with specialist pain input if pain remains uncontrolled, revascularisation is inappropriate or pain persists after treatment. Protect the foot, arrange wound and podiatry care, assess for infection and avoid assuming that antibiotics or debridement alone can compensate for inadequate perfusion. Do not offer major amputation until revascularisation options have been considered by the vascular multidisciplinary team.^1,2	NICE CG147 recommendations 1.6.1 to 1.6.11
Safety-net acute deterioration and arrange follow-up	Give urgent return advice for sudden or rapidly worsening pain, pallor, coldness, numbness, weakness, new tissue colour change, worsening ulceration, fever or systemic illness. These features may represent acute limb ischaemia or infected CLTI and require same-day emergency vascular assessment, not routine PAD follow-up. Continue secondary prevention and review exercise, symptoms, wounds, treatment adherence and cardiovascular risk.^1,2,6,3	NICE CG147, NICE CKS PAD and NHS PAD information

Illustrations

Supply-demand mismatch in claudicationGraph showing oxygen demand rising with exercise against a fixed, stenosis-limited maximal supply, illustrating why pain appears at a reproducible walking distance.PassFinals · original

Progression from claudication to chronic limb-threatening ischaemiaDiagram illustrating progression from asymptomatic disease through intermittent claudication to rest pain, ulceration and gangrene as perfusion falls.PassFinals · original

Ischaemic arterial ulceration and toe necrosisClinical photograph of a distal arterial ulcer over a pressure point with a pale base, showing tissue loss that requires vascular assessment.Bondegezou, Wikimedia Commons · CC-BY-SA-4.0

Differentials

Neurogenic claudication

Pain or weakness triggered by standing/walking and relieved by sitting or spinal flexion, often with neurological or back symptoms and preserved pulses.

Chronic venous disease

Oedema, venous eczema and gaiter-area ulceration rather than distal ischaemic pain and absent pulses.

Diabetic peripheral neuropathy

Burning or numb stocking-distribution symptoms that may coexist with PAD; preserved pulses do not exclude neuropathy and neuropathy does not exclude PAD.

Musculoskeletal or arthritic pain

Pain related to joints, movement or posture rather than a reproducible vascular walking distance.

Acute limb ischaemia

Sudden pain, pallor, coldness, pulse loss, paraesthesia or weakness requiring an emergency vascular pathway.

Complications

Chronic limb-threatening ischaemia with rest pain, ulceration or gangrene
Infection, non-healing wounds and major amputation
Acute limb ischaemia from plaque thrombosis or embolism
Myocardial infarction and stroke from systemic atherosclerosis
Reduced mobility, falls, depression and loss of independence
Restenosis or graft failure after revascularisation

Prognosis

Intermittent claudication often remains stable or improves with cardiovascular risk reduction and supervised exercise, but symptoms can remain disabling. CLTI carries a high risk of tissue loss and amputation and needs urgent vascular MDT care. Long-term prognosis is strongly influenced by systemic cardiovascular disease, smoking and diabetes.

Guidelines

Peripheral arterial disease: diagnosis and management (CG147) (NICE, 2012)
April 2026 exceptional surveillance of CG147 (NICE, 2026)

References

NICE CG147: Peripheral arterial disease: diagnosis and management (CG147 recommendations; current page reviewed 27 April 2026)Published 8 Aug 2012 | Updated 11 Dec 2020
NICE CKS: Peripheral arterial disease (Current NICE CKS topic for assessment and management)
NHS: Peripheral arterial disease treatment (NHS exercise, smoking, medicines and revascularisation information, reviewed 10 April 2026)Updated 10 Apr 2026
NICE NG238: Cardiovascular disease: risk assessment and reduction, including lipid modification (NG238 recommendations)Published 14 Dec 2023
NICE CG147: April 2026 exceptional surveillance decision (Update planned for drug-eluting stents and drug-coated balloon angioplasty in femoropopliteal CLTI)Published 27 Apr 2026
NHS: Peripheral arterial disease diagnosis (NHS diagnosis and ABPI information, reviewed 10 April 2026)Updated 10 Apr 2026
NICE QS52: Peripheral arterial disease quality standard (Quality statement 3: supervised exercise programmes)Published 21 Jan 2014

Evidence checked: 2026-08-03

This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.