The cardiac magnetic resonance myocardial perfusion reserve index in the assessment of the revascularised left anterior descending artery

Objectives Myocardial perfusion reserve (MPR) is the ratio of maximum hyperaemic to rest myocardial blood flow, quantified with contrast-enhanced cardiac magnetic resonance (CMR) T1-weighted dynamic imaging and signal intensity-time curves of first-pass contrast. The assessment of myocardial perfusion post bypass grafting may be confounded by reduced systolic function and scar. Using a 32channel cardiac coil array, we assessed the accuracy of the MPR index (MPRI) in the revascularised left anterior descending (LAD) artery.