Near-Infrared Spectroscopy Enhances Intravascular Ultrasound Assessment of Vulnerable Coronary Plaque: A Combined Pathological and In Vivo Study

Rishi Puri; Ryan D Madder; Sean P Madden; Stephen T Sum; Kathy Wolski; James E Muller; Jordan Andrews; Karilane L King; Yu Kataoka; Kiyoko Uno; Samir R Kapadia; E Murat Tuzcu; Steven E Nissen; Renu Virmani; Akiko Maehara; Gary S Mintz; Stephen J Nicholls

doi:10.1161/ATVBAHA.115.306118

Near-Infrared Spectroscopy Enhances Intravascular Ultrasound Assessment of Vulnerable Coronary Plaque: A Combined Pathological and In Vivo Study

Arterioscler Thromb Vasc Biol. 2015 Nov;35(11):2423-31. doi: 10.1161/ATVBAHA.115.306118. Epub 2015 Sep 3.

Authors

Rishi Puri¹, Ryan D Madder¹, Sean P Madden¹, Stephen T Sum¹, Kathy Wolski¹, James E Muller¹, Jordan Andrews¹, Karilane L King¹, Yu Kataoka¹, Kiyoko Uno¹, Samir R Kapadia¹, E Murat Tuzcu¹, Steven E Nissen¹, Renu Virmani¹, Akiko Maehara¹, Gary S Mintz¹, Stephen J Nicholls²

Affiliations

¹ From the Cleveland Clinic Coordinating Center for Clinical Research (C5R) (R.P., K.W., K.L.K., K.U., S.E.N.), and Department of Cardiovascular Medicine (R.P., S.R.K., E.M.T., S.E.N.), Cleveland Clinic, OH; Department of Medicine, University of Adelaide, South Australia (R.P., S.J.N.); Frederik Meijer Heart and Vascular Institute, Spectrum Health, Grand Rapids, MI (R.D.M.); InfraRedX Inc., Burlington, MA (S.P.M., S.T.S., J.E.M.); South Australian Health and Medical Research Institute, Adelaide, South Australia (J.A., Y.K., S.J.N.); CVPath Institute, Gaithersburg, MD (R.V.); and Cardiovascular Research Foundation, New York, NY (A.M., G.S.M.).
² From the Cleveland Clinic Coordinating Center for Clinical Research (C5R) (R.P., K.W., K.L.K., K.U., S.E.N.), and Department of Cardiovascular Medicine (R.P., S.R.K., E.M.T., S.E.N.), Cleveland Clinic, OH; Department of Medicine, University of Adelaide, South Australia (R.P., S.J.N.); Frederik Meijer Heart and Vascular Institute, Spectrum Health, Grand Rapids, MI (R.D.M.); InfraRedX Inc., Burlington, MA (S.P.M., S.T.S., J.E.M.); South Australian Health and Medical Research Institute, Adelaide, South Australia (J.A., Y.K., S.J.N.); CVPath Institute, Gaithersburg, MD (R.V.); and Cardiovascular Research Foundation, New York, NY (A.M., G.S.M.). stephen.nicholls@sahmri.com.

PMID: 26338299
DOI: 10.1161/ATVBAHA.115.306118

Abstract

Objectives: Pathological studies demonstrate the dual significance of plaque burden (PB) and lipid composition for mediating coronary plaque vulnerability. We evaluated relationships between intravascular ultrasound (IVUS)-derived PB and arterial remodeling with near-infrared spectroscopy (NIRS)-derived lipid content in ex vivo and in vivo human coronary arteries.

Approach and results: Ex vivo coronary NIRS and IVUS imaging was performed through blood in 116 coronary arteries of 51 autopsied hearts, followed by 2-mm block sectioning (n=2070) and histological grading according to modified American Heart Association criteria. Lesions were defined as the most heavily diseased 2-mm block per imaged artery on IVUS. IVUS-derived PB and NIRS-derived lipid core burden index (LCBI) of each block and lesion were analyzed. Block-level analysis demonstrated significant trends of increasing PB and LCBI across more complex atheroma (Ptrend <0.001 for both LCBI and PB). Lesion-based analyses demonstrated the highest LCBI and remodeling index within coronary fibroatheroma (Ptrend <0.001 and 0.02 versus all plaque groups, respectively). Prediction models demonstrated similar abilities of PB, LCBI, and remodeling index for discriminating fibroatheroma (c indices: 0.675, 0.712, and 0.672, respectively). A combined PB+LCBI analysis significantly improved fibroatheroma detection accuracy (c index 0.77, P=0.028 versus PB; net-reclassification index 43%, P=0.003), whereas further adding remodeling index did not (c index 0.80, P=0.27 versus PB+LCBI). In vivo comparisons of 43 age- and sex-matched patients (to the autopsy cohort) undergoing combined NIRS-IVUS coronary imaging yielded similar associations to those demonstrated ex vivo.

Conclusions: Adding NIRS to conventional IVUS-derived PB imaging significantly improves the ability to detect more active, potentially vulnerable coronary atheroma.

Keywords: artherosclerotic plaque; coronary artery disease; intravascular imaging; remodeling; vulnerable plaque.

MeSH terms

Aged
Autopsy
Biomarkers / analysis
Coronary Artery Disease / diagnosis*
Coronary Artery Disease / diagnostic imaging
Coronary Artery Disease / metabolism
Coronary Artery Disease / pathology
Coronary Artery Disease / therapy
Coronary Vessels* / chemistry
Coronary Vessels* / diagnostic imaging
Coronary Vessels* / pathology
Female
Fibrosis
Humans
Lipids / analysis*
Male
Middle Aged
Percutaneous Coronary Intervention
Plaque, Atherosclerotic*
Predictive Value of Tests
Prognosis
Spectroscopy, Near-Infrared*
Ultrasonography, Interventional*
Vascular Remodeling

Substances

Biomarkers
Lipids