steal phenomenon
Diversion of blood flow from one vascular territory to another through collateral circulation, causing ischemia.
Full Definition
Steal phenomenon describes the pathophysiological process where blood flow is diverted from one vascular territory to another area of lower resistance through collateral circulation, resulting in relative ischemia of the donor territory. This occurs when proximal arterial stenosis or occlusion causes pressure gradients that redirect flow. Classic examples include subclavian steal syndrome (vertebrobasilar insufficiency due to subclavian stenosis) and dialysis access steal syndrome (hand ischemia due to arteriovenous fistula). The phenomenon can be demonstrated during provocative maneuvers that increase flow demands.
Usage
Usage note: Specify anatomical location when known (e.g., subclavian steal, dialysis access steal).
In Context
- "Duplex ultrasonography demonstrated subclavian steal phenomenon with flow reversal in the vertebral artery." — Vascular laboratory report
- "The patient developed steal phenomenon following dialysis access creation, resulting in hand ischemia." — Nephrology consultation