myocardial perfusion reserve
Ratio of maximal coronary flow during stress to resting flow, indicating coronary vascular function and epicardial stenosis severity.
Full Definition
Myocardial perfusion reserve (MPR), also known as coronary flow reserve, represents the capacity of the coronary circulation to increase blood flow in response to maximal vasodilation. It is calculated as the ratio of hyperemic to baseline myocardial blood flow and reflects the combined function of epicardial coronary arteries and coronary microcirculation. Normal MPR values are typically > 2.0, while values < 2.0 suggest either epicardial coronary stenosis or microvascular dysfunction. MPR can be measured using various imaging modalities including PET, CMR perfusion, and echocardiography, and provides important prognostic information beyond conventional perfusion imaging.
Usage
Usage note: Report as ratio; specify whether global or regional values. Normal MPR > 2.0.
In Context
- "Quantitative perfusion analysis revealed reduced myocardial perfusion reserve of 1.6 in the LAD territory." — PET perfusion report
- "Global myocardial perfusion reserve was preserved at 2.8, suggesting absence of significant epicardial disease." — CMR perfusion study