collateral circulation
Alternative blood flow pathways that develop to supply myocardium when primary coronary arteries are significantly narrowed or occluded.
Full Definition
Collateral circulation refers to the network of small vessels that can develop or enlarge to provide alternative blood flow pathways to myocardium when the primary coronary arteries are significantly stenosed or occluded. These collateral vessels may be inter-coronary (connecting different coronary territories) or intra-coronary (within the same coronary distribution). Well-developed collaterals can provide significant protection against ischemia and may improve outcomes in patients with chronic coronary artery disease. In cardiovascular imaging, collateral assessment includes grading their size, extent, and functional significance. The Rentrop classification system is commonly used to grade collateral flow angiographically.
Usage
Usage note: Should specify grade/quality and source of collateral flow when documenting.
In Context
- "Extensive collateral circulation from the RCA was noted, providing Grade 3 filling of the occluded LAD territory." — Angiographic assessment
- "Poor collateral development explained the patient's severe symptoms despite chronic coronary occlusion." — Clinical correlation