What is collateral circulation?

Collateral circulation refers to the development of alternative pathways for blood flow around a blockage in the vascular system. When a primary blood vessel is obstructed due to conditions such as atherosclerosis or thrombosis, collateral vessels can form or become more prominent to help supply blood to affected areas. This adaptation is crucial because it helps maintain perfusion to tissues that might otherwise suffer from ischemia, ensuring they receive the necessary oxygen and nutrients for proper function.

The other choices do not accurately describe collateral circulation. The flow of blood through the heart's valves pertains to the functioning of the heart but does not relate to alternative pathways around blockages. The movement of lymph fluid in the body concerns the lymphatic system, which is separate from blood circulation. The distribution of oxygen-rich blood describes a general function of the cardiovascular system but does not specifically address how the body compensates for blocked blood vessels.