Subclavian Steal Syndrome

A patient who develops dizziness, visual disturbance, ataxia, or syncope while using one arm—and has a lower systolic pressure in that arm—has a pattern that should prompt consideration of subclavian steal syndrome. The lesion is proximal subclavian obstruction; the clinical consequence is reduced posterior-circulation perfusion when arm demand rises. The bedside questions are therefore linked: Which arm has lower pressure and weaker pulse? Do symptoms appear with that arm’s activity? Is the patient asymptomatic, exertionally symptomatic, or deteriorating now? Those answers guide the move from vascular-risk management to revascularization urgency.