2.6 Peripheral Arterial Disease, Aortic Aneurysm & Venous Disease
Key Takeaways
An ankle-brachial pressure index below 0.9 indicates peripheral arterial disease; values above about 1.3–1.4 suggest calcified, incompressible arteries, common in diabetes and CKD.
NICE CG147 offers people with intermittent claudication a supervised exercise programme (about 2 hours a week for 3 months) before considering revascularisation.
Acute limb ischaemia presents with the 6 Ps and needs IV heparin and an immediate vascular surgical opinion; fixed mottling and paralysis suggest an irreversible limb.
The NHS AAA Screening Programme offers men a one-off ultrasound in the year they turn 65; an aneurysm of 5.5 cm or more needs vascular referral within 2 weeks.
Compression bandaging for a venous leg ulcer is applied only after the ABPI has excluded significant arterial disease.
Peripheral Arterial Disease, Aortic Aneurysm & Venous Disease
Chronic Peripheral Arterial Disease (PAD)
Atherosclerosis of the leg arteries shares the risk factors of coronary disease: smoking (the strongest), diabetes, hypertension, hyperlipidaemia and age.
- Intermittent claudication: cramping calf, thigh or buttock pain on walking, relieved by rest within minutes. Buttock claudication with erectile dysfunction suggests aorto-iliac disease (Leriche syndrome).
- Critical limb-threatening ischaemia (CLTI): rest pain (often in the foot at night, eased by hanging the leg over the bed), ulceration or gangrene. It needs urgent vascular referral.
- Signs: absent pulses, cool pale skin, hair loss, thin shiny skin, delayed capillary refill, Buerger's test (pallor on elevation, dependent rubor).
Ankle-Brachial Pressure Index (ABPI)
| ABPI | Interpretation |
|---|---|
| 0.9–1.3 | Normal range; PAD unlikely (if the history fits, consider exercise ABPI or toe pressures) |
| Below 0.9 | Peripheral arterial disease |
| Below about 0.5 | Severe disease, often CLTI |
| Above about 1.3–1.4 | Incompressible calcified arteries (diabetes, CKD); the reading is falsely reassuring, so use toe pressures or duplex |
Management (NICE CG147)
- Secondary prevention: stop smoking, atorvastatin 80 mg, an antiplatelet (clopidogrel 75 mg is first-line), blood pressure and diabetes control.
- Supervised exercise programme (for example 2 hours of supervised exercise a week for 3 months).
- Naftidrofuryl oxalate may be considered if exercise has not helped and the patient prefers not to have revascularisation.
- Revascularisation (angioplasty with or without stent, or bypass grafting) after duplex, CT or MR angiography when symptoms remain limiting, or for CLTI.
Acute Limb Ischaemia
A sudden fall in limb perfusion threatening viability, caused by embolism (usually from the heart in atrial fibrillation; sudden onset, no previous claudication, normal pulses in the other leg) or thrombosis on an existing atherosclerotic plaque or graft (previous claudication, reduced pulses elsewhere).
- The 6 Ps: Pain, Pallor, Pulselessness, Paraesthesia, Perishing cold and Paralysis. Sensory loss and paralysis mean the limb is threatened.
- Management: analgesia, IV unfractionated heparin, and an immediate vascular surgery opinion for embolectomy, catheter-directed thrombolysis or bypass. Fixed mottling and a tense, paralysed limb indicate irreversible ischaemia (amputation or palliation).
- After revascularisation, watch for reperfusion injury: compartment syndrome (needing fasciotomy), hyperkalaemia, acidosis and myoglobinuric AKI.
Abdominal Aortic Aneurysm (AAA)
An infrarenal aortic diameter of 3.0 cm or more. Risk factors are male sex, age, smoking, hypertension and family history.
NHS AAA Screening Programme
Men are invited for a one-off abdominal ultrasound in the year they turn 65; older men who were never screened can self-refer.
| Aortic Diameter | Category | Action |
|---|---|---|
| Below 3.0 cm | Normal | Discharged from screening |
| 3.0–4.4 cm | Small | Annual ultrasound surveillance |
| 4.5–5.4 cm | Medium | 3-monthly ultrasound surveillance |
| 5.5 cm or more | Large | Refer to a vascular surgeon within 2 weeks for repair (EVAR or open) |
Repair is also considered for symptomatic aneurysms (tenderness, back or abdominal pain) or rapid growth (more than 1 cm a year). Surveillance includes smoking cessation, blood pressure control and a statin.
Ruptured AAA
Sudden abdominal or back pain, collapse and a pulsatile abdominal mass in an older man. Shock may be masked at first. Call the vascular team immediately; use permissive hypotension (avoid aggressive fluids); a haemodynamically unstable patient with a known AAA goes straight to theatre without waiting for CT.
Venous Disease
Varicose Veins (NICE CG168)
Dilated, tortuous superficial veins caused by valve incompetence. Refer to a vascular service if they are symptomatic (aching, heaviness, itching), cause skin changes (pigmentation, venous eczema, lipodermatosclerosis), have caused superficial vein thrombosis or bleeding, or there is an active or healed venous leg ulcer. Duplex ultrasound confirms reflux. Treatment order: endothermal ablation (radiofrequency or laser), then ultrasound-guided foam sclerotherapy, then surgery. Compression hosiery is not first-line unless intervention is unsuitable.
Leg Ulcers
| Feature | Venous Ulcer | Arterial Ulcer | Neuropathic Ulcer |
|---|---|---|---|
| Site | Gaiter area, often above the medial malleolus | Toes, heels, pressure points | Plantar pressure points (metatarsal heads) |
| Appearance | Shallow, irregular, sloping edges, granulating base | Punched-out, deep, pale base | Punched-out with surrounding callus |
| Pain | Mild, eased by elevation | Severe, worse on elevation and at night | Painless |
| Surrounding skin | Haemosiderin staining, eczema, lipodermatosclerosis, oedema | Cold, hairless, absent pulses | Warm, pulses often present, reduced sensation |
| Treatment | Compression bandaging after ABPI confirms adequate arterial supply | Vascular referral and revascularisation | Off-loading, diabetic foot team |
Warning
Check the ABPI Before Compression: Compression bandaging on a leg with significant arterial disease can cause pressure necrosis and limb loss. Full compression is usually applied only when the ABPI is about 0.8 or above, with specialist input for lower values or for incompressible vessels.
Superficial Vein Thrombosis
A tender, red, hard cord along a superficial vein. Arrange duplex ultrasound to exclude extension into the deep veins (DVT), especially near the saphenofemoral junction, which may need anticoagulation.
Raynaud's Phenomenon
Episodic digital vasospasm triggered by cold or stress, with colour change from white (ischaemia) to blue (cyanosis) to red (reperfusion). Primary Raynaud's affects young women with no underlying cause. Secondary Raynaud's (later onset, asymmetrical, ulcers, abnormal nailfold capillaries) suggests systemic sclerosis, SLE, vibration injury or drugs (beta-blockers). Management: keep warm and stop smoking; nifedipine if symptoms are troublesome; urgent referral for digital ulcers or gangrene.
A 66-year-old man attends AAA screening and an ultrasound shows an infrarenal aortic diameter of 5.7 cm. He has no symptoms. What is the most appropriate next step?
Vascular surgical referral within 2 weeks
Discharge from the AAA screening programme
Repeat ultrasound surveillance in 12 months
Repeat ultrasound surveillance in 3 months
A 72-year-old woman with atrial fibrillation who stopped her apixaban 2 weeks ago develops sudden severe pain in her right leg. The leg is pale, cold and pulseless below the femoral artery, with reduced sensation in the foot but preserved movement. The left leg pulses are normal. What is the most appropriate immediate management?
Arrange outpatient arterial duplex ultrasound
IV heparin and immediate vascular surgical review
Start clopidogrel and a supervised exercise programme
Elevate the leg and apply compression bandaging
A 70-year-old man has a shallow, painless ulcer above the medial malleolus with surrounding brown pigmentation and eczema. His foot pulses are difficult to feel. What should be done before starting compression bandaging?
Prescribe topical corticosteroid to the ulcer base
Swab the ulcer and start oral flucloxacillin
Measure the ankle-brachial pressure index
Arrange an urgent skin biopsy
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