Relationship between extent of residual myocardial viability and coronary flow reserve in patients with recent myocardial infarction

Background The presence of viability in an infarct zone implies an intact microvasculature. We hypothesized that coronary flow reserve (CFR), which assesses the microcirculation, would correlate with the extent of viability in infarction zones. Methods CFR was measured after stenting in 17 patients with single vessel disease >48 hours from infarction. Viability was determined with use of single-photon emission computed tomography sestamibi imaging. Results Sestamibi uptake in the infarct zone correlated with CFR in the infarct artery (r = 0.62, P = .008) and sestamibi uptake in the infarct zone was greater in patients with normal CFR than in patients with abnormal CFR (61.9 +/- 9.1% vs 46.3 +/- 9.6%, P = .004). In addition, CFR was greater in patients with viability compared with patients without viability (2.4 +/- 1.3 vs 1.4 +/- 0.4, P = .015). Conclusions CFR correlates with the extent of viability after infarction. Preserved CFR in an infarct-related artery implies preserved viability.