Murray law-based quantitative flow ratio for assessment of nonculprit lesions in patients with ST-segment elevation myocardial infarction.

INTRODUCTION

Revascularization of nonculprit arteries in patients with ST-Segment Elevation Myocardial Infarction (STEMI) is now recommended based on several trials. However, the optimal therapeutic strategy of nonculprit lesions remains unknown. Murray law-based Quantitative Flow Ratio (μQFR) is a novel, non-invasive, vasodilator-free method for evaluating the functional severity of coronary artery stenosis, which has potential applications for nonculprit lesion assessment in STEMI patients.

MATERIAL AND METHODS

Patients with STEMI who received staged PCI before hospital discharge were enrolled retrospectively. μQFR analyses of nonculprit vessels were performed based on both acute and staged angiography.

RESULTS

Eighty-four patients with 110 nonculprit arteries were included. The mean acute μQFR was 0.76 ± 0.18, and the mean staged μQFR was 0.75 ± 0.19. The average period between acute and staged evaluation was 8 days. There was a good correlation (r = 0.719, P < 0.001) between acute μQFR and staged μQFR. The classification agreement was 89.09%. The area under the receiver operator characteristic (ROC) curve for detecting staged μQFR ≤ 0.80 was 0.931.

CONCLUSIONS

It is feasible to calculate the μQFR during the acute phase of STEMI patients. Acute μQFR and staged μQFR have a good correlation and agreement. The μQFR could be a valuable method for assessing functional significance of nonculprit arteries in STEMI patients.