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Chronic limb-threatening ischaemia (CLTI) — assessment and revascularisation
CLTI is peripheral arterial disease with rest pain, a non-healing ulcer or gangrene; assessment includes ankle and toe pressures, WIfI limb staging and GLASS anatomic staging, and the goal is prompt revascularisation — vein bypass when there is a good-quality saphenous vein and suitable disease, or endovascular treatment — alongside best medical therapy, with primary amputation only for an unsalvageable limb or a non-ambulatory patient.
Why it matters in the exam
This is the most frequently asked topic in vascular surgery. The definition by the Global Vascular Guidelines (2019): proven arterial disease with rest pain, or an ulcer or gangrene lasting more than 2 weeks. Supporting haemodynamic findings: ankle pressure below 50 mmHg, ABI below 0.4, toe pressure below 30 mmHg or TcPO2 below 30 mmHg. In a diabetic patient the ankle arteries are calcified so the ABI may be falsely high (above 1.3), and toe pressure is used. WIfI staging assesses the wound, the severity of ischaemia and infection, and predicts amputation risk and benefit from revascularisation; GLASS grades the complexity of the anatomic disease. The approach is summed up in the word PLAN: Patient risk, Limb severity and ANatomic pattern.
Two randomised trials guide the choice: BEST-CLI (2022) showed that in patients with a good-quality great saphenous vein surgical bypass reduced major limb events or death compared with endovascular treatment; BASIL-2 (2023) showed that in infrapopliteal disease endovascular treatment first achieved better amputation-free survival than vein bypass. So the decision is individual: for long disease with a good vein in a fit patient — vein bypass; for a high-risk patient, short lesions or no suitable vein — endovascular treatment. Autologous vein is always preferred over prosthetic graft, especially below the knee. All patients receive best medical therapy: smoking cessation, high-intensity statin, antiplatelet therapy, and after revascularisation also rivaroxaban 2.5 mg twice daily with aspirin (VOYAGER PAD). Deep infection or a foot abscess is drained urgently before revascularisation.
Primary amputation suits a bedbound patient, a limb with extensive unsalvageable gangrene, or a patient with a very short life expectancy.
Key points
- CLTI — rest pain, ulcer or gangrene beyond 2 weeks.
- Toe pressure below 30 mmHg — significant ischaemia.
- WIfI and GLASS stage the disease.
- Good vein — bypass; high risk — endovascular.
- Best medical therapy for all.
Summary table
| Stage | Tool | Key points |
|---|---|---|
| Diagnosis | ABI, toe pressure, TcPO2 | Ankle below 50 mmHg, toe below 30 mmHg |
| Limb staging | WIfI | Wound, ischaemia, infection — amputation risk |
| Anatomic staging | GLASS | Disease complexity |
| Vein bypass | Good-quality great saphenous vein, fit patient | BEST-CLI: preferred in these patients |
| Endovascular treatment | High risk, short lesions, no vein | BASIL-2: preferred in infrapopliteal disease |
| Primary amputation | Unsalvageable limb, non-ambulatory patient | Not every limb needs revascularisation |
In the full version for subscribers
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Sources
- Global Vascular Guidelines on the management of chronic limb-threatening ischemia (SVS/ESVS/WFVS), 2019 — Staging, revascularisation strategy and amputation
- Farber et al., BEST-CLI, N Engl J Med, 2022 — Surgery or endovascular therapy for chronic limb-threatening ischemia
- Bradbury et al., BASIL-2, Lancet, 2023 — Vein bypass first versus best endovascular treatment first for infrapopliteal disease
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.