Intracoronary NIRS accurately differentiated STEMI culprit from nonculprit segments (c-statistic=0.83; P<0.001), with culprit segments having a 4.4-fold greater median maxLCBI4mm.
Observational (n=75)
Blinded core laboratory analysis
Yes
Does intracoronary near-infrared spectroscopy (NIRS) accurately differentiate STEMI culprit from nonculprit segments using a maxLCBI4mm threshold?
Intracoronary NIRS accurately differentiates STEMI culprit from nonculprit segments, confirming that a maxLCBI4mm ≥400 threshold identifies lipid-rich plaques underlying STEMI.
Effect estimate: c-statistic 0.83
Absolute Event Rate: 543% vs 123%
p-value: p=<0.001
OBJECTIVE: 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. APPROACH AND RESULTS: At 2 centers in the United States and Sweden, 75 STEMI patients underwent intracoronary NIRS imaging after establishing thrombolysis in myocardial infarction 3 flow, but before stenting. Blinded core laboratory analysis defined the culprit segment as the 10-mm segment distal to the proximal angiographic culprit margin. The remaining vessel was divided into contiguous 10-mm nonculprit segments. The maxLCBI4mm of culprit segments (median interquartile range: 543 273-756) was 4.4-fold greater than nonculprit segments (median interquartile range: 123 0-307; P<0.001). Receiver-operating characteristic analysis demonstrated that maxLCBI4mm differentiated culprit from nonculprit segments with high accuracy (c-statistic=0.83; P<0.001). A threshold maxLCBI4mm ≥400 identified STEMI culprit segments with a sensitivity of 64% and specificity of 85%. CONCLUSIONS: This study substantiates the ability of NIRS to accurately differentiate STEMI culprit from nonculprit segments and confirms that a threshold maxLCBI4mm ≥400 is detected by NIRS in the majority of STEMI culprits.
Madder et al. (Fri,) conducted a observational in ST-segment-elevation myocardial infarction (STEMI) (n=75). Intracoronary near-infrared spectroscopy (NIRS) of culprit segments vs. Nonculprit segments was evaluated on Maximum lipid core burden index in 4 mm (maxLCBI4mm) (c-statistic 0.83, p=<0.001). Intracoronary NIRS accurately differentiated STEMI culprit from nonculprit segments (c-statistic=0.83; P<0.001), with culprit segments having a 4.4-fold greater median maxLCBI4mm.