coronary flow reserve
Ratio of maximum achievable coronary flow during hyperemia to resting coronary flow.
Full Definition
Coronary flow reserve (CFR) is a physiological measure representing the ratio of maximal coronary blood flow during pharmacological hyperemia to baseline resting coronary flow. CFR reflects the functional capacity of the entire coronary circulation, including epicardial vessels, microvascular resistance vessels, and collateral circulation. Normal CFR values typically exceed 2.0-2.5, with reduced values indicating coronary circulatory dysfunction from epicardial stenosis, microvascular disease, or both. CFR can be measured using various techniques including Doppler flow wire, positron emission tomography, or cardiac magnetic resonance imaging. Unlike FFR, CFR provides information about both epicardial and microvascular function but is influenced by hemodynamic conditions and microvascular dysfunction.
Usage
Usage note: Distinguish from FFR - CFR assesses entire coronary circulation, FFR assesses epicardial stenosis
In Context
- "Coronary flow reserve was reduced at 1.8, suggesting microvascular dysfunction." — Physiology assessment
- "CFR measurement complemented FFR evaluation for comprehensive coronary assessment." — Invasive physiology study