coronary flow reserve
Also written as: CFR — Coronary Flow Reserve
The ratio of maximum coronary blood flow during hyperemia to baseline resting flow.
Full Definition
Coronary flow reserve (CFR) represents the ability of the coronary circulation to increase blood flow in response to maximal vasodilation, typically expressed as the ratio of hyperemic to baseline flow. Normal CFR values are generally above 2.5, with reduced values indicating microvascular dysfunction or epicardial coronary stenosis. Assessment of CFR can be performed using various modalities including transthoracic Doppler, positron emission tomography, or invasive coronary wire measurements. This parameter is particularly valuable in evaluating patients with chest pain and non-obstructive coronary disease.
Usage
Usage note: Express as a dimensionless ratio; normal values typically >2.5.
In Context
- "Impaired coronary flow reserve of 1.8 suggested significant microvascular dysfunction." — Nuclear cardiology report
- "The patient's symptoms persisted despite normal epicardial arteries and preserved coronary flow reserve." — Cardiology consultation note