Educational draft · awaiting clinical reviewUse Rapid for revision, not patient-care decisions. Check current national and local guidance and the BNF or BNFC before acting.
2 min synopsisUK scopeSources checked 12 Sept 2026Clinical review pending
Saved on this device
!
Do not label acute stroke as steal
Persistent focal neurological deficit, inability to walk, dysarthria, diplopia or reduced consciousness is an acute stroke presentation even when subclavian disease is known.
Action: Activate the hyperacute stroke pathway, document last-known-well and obtain urgent brain and vascular imaging; do not delay reperfusion assessment for outpatient steal testing.
Synopsis
Recognise clinically important subclavian steal, confirm its haemodynamic cause and select medical or revascularisation management safely.
Subclavian steal syndrome requires symptoms plus proximal subclavian obstruction and ipsilateral vertebral flow diversion; retrograde vertebral flow alone is a haemodynamic finding.
Persistent focal deficit, severe limb ischaemia or exertional angina after an internal mammary graft is urgent and must not wait for routine duplex follow-up.
Measure blood pressure in both arms and assess pulses, bruits, arm ischaemia and a complete posterior-circulation neurological examination.
Key red flags
A persistent posterior-circulation deficit or reduced consciousness requires emergency stroke assessment rather than elective vascular investigation.
Rest pain, digital cyanosis, tissue loss or a cold pulseless arm indicates severe limb ischaemia and needs urgent vascular review.
Angina during left-arm exertion after an internal mammary coronary bypass may be coronary-subclavian steal and needs urgent cardiology and vascular assessment.
Syncope without a reproducible arm relationship still requires assessment for arrhythmia, haemorrhage and other dangerous causes.
Upper-limb ischaemia
Fatigue, claudication, coolness or delayed exertional recovery can coexist; rest pain and tissue loss indicate more severe arterial compromise.
Coronary-subclavian steal
Angina triggered by ipsilateral arm exercise in a patient with an internal mammary coronary graft suggests diversion from the coronary conduit.
Investigation priorities
01
Bilateral arm blood pressuresFirst step
Screen for an inflow pressure gradient and choose a reliable arm for future management.
Management branches
ASSESSEvaluate suspected symptomatic steal
Arm exertion produces vertebrobasilar symptoms or ipsilateral upper-limb ischaemia with pulse asymmetry.
Establish onset, duration, reproducibility and focal features, then examine both arms, pulses, supraclavicular bruits and the complete neurological system.
Measure blood pressure in both arms and assess for severe hand ischaemia, an internal mammary coronary graft and haemodialysis access.
Key medicines
AtorvastatinOffer 80 mg orally once daily for established atherosclerotic cardiovascular disease unless interactions, adverse-effect risk or patient preference support a lower dose; review lipid response after two to three months.Check liver transaminases, interacting medicines, pregnancy potential and muscle symptoms; use a lower starting dose when comorbidity or interaction risk warrants it.
ClopidogrelWhen symptomatic atherosclerotic arterial disease supports single-antiplatelet therapy, use 75 mg orally once daily long term, subject to the chosen indication and review.Review active bleeding, severe hepatic impairment, bruising, blood dyscrasia and CYP2C19 interactions; reversed vertebral flow alone does not mandate treatment.
National guidance is shown before implementation-dependent detail. Typical adult dose examples remain subject to patient factors, contraindications and the live BNF or specialist protocol. Source check completed 12 Sept 2026; clinical approval remains outstanding.