Confirmation of the Intracoronary Near-Infrared Spectroscopy Threshold of Lipid-Rich Plaques That Underlie ST-Segment-Elevation Myocardial Infarction.

In a previous exploratory analysis, intracoronary near-infrared spectroscopy (NIRS) found the majority of culprit lesions in ST-segment-elevation myocardial infarction (STEMI) to contain a maximum lipid core burden index in 4 mm (maxLCBI4mm) of >400. This initial study was limited by a small sample size, enrollment at a single center, and post hoc selection of the maxLCBI4mm ≥400 threshold. This study was designed a priori to substantiate the ability of NIRS to discriminate STEMI culprit from nonculprit segments and to confirm the performance of the maxLCBI4mm ≥400 threshold.