Coronary lipid-rich plaque characteristics in Japanese patients with acute coronary syndrome and stable angina: A near infrared spectroscopy and intravascular ultrasound study

Norihito Takahashi; Tomotaka Dohi; Hirohisa Endo; Mitsuhiro Takeuchi; Shinichiro Doi; Yoshiteru Kato; Iwao Okai; Hiroshi Iwata; Shinya Okazaki; Kikuo Isoda; Katsumi Miyauchi; Tohru Minamino

doi:10.1016/j.ijcha.2021.100747

Coronary lipid-rich plaque characteristics in Japanese patients with acute coronary syndrome and stable angina: A near infrared spectroscopy and intravascular ultrasound study

Int J Cardiol Heart Vasc. 2021 Mar 11:33:100747. doi: 10.1016/j.ijcha.2021.100747. eCollection 2021 Apr.

Authors

Affiliations

¹ Department of Cardiovascular Biology and Medicine, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
² Japan Agency for Medical Research and Development Core Research for Evolutionary Medical Science and Technology (AMEDCREST), Japan Agency for Medical Research and Development, 1-7-1 Otemachi, Chiyoda-ku, Tokyo, Japan.

Abstract

Background: Asians have a much lower incidence of adverse coronary events than Caucasians. We sought to evaluate the characteristics of coronary lipid-rich plaques (LRP) in Asian patients with acute coronary syndrome (ACS) and stable angina (SA). We also aimed to identify surrogate markers for the extent of LRP.

Methods: We evaluated 207 patients (ACS, n = 75; SA, n = 132) who underwent percutaneous coronary intervention under near infrared spectroscopy intravascular ultrasound (NIRS-IVUS). Plaque characteristics and the extent of LRP [defined as a long segment with a 4-mm maximum lipid-core burden index (maxLCBI_4mm)] on NIRS in de-novo culprit and non-culprit segments were analyzed.

Results: The ACS culprit lesions had a significantly higher maxLCBI_4mm (median [interquartile range (IQR)]: 533 [385-745] vs. 361 [174-527], p < 0.001) than the SA culprit lesions. On multivariate logistic analysis, a large LRP (defined as maxLCBI_4mm ≥ 400) was the strongest independent predictor of the ACS culprit segment (odds ratio, 3.87; 95% confidence interval, 1.95-8.02). In non-culprit segments, 19.8% of patients had at least one large LRP without a small lumen. No significant correlation was found between the extent of LRP and systematic biomarkers (hs-CRP, IL-6, TNF-α), whereas the extent of LRP was positively correlated with IVUS plaque burden (r = 0.24, p < 0.001).

Conclusions: We confirmed that NIRS-IVUS plaque assessment could be useful to differentiate ACS from SA culprit lesions, and that a threshold maxLCBI_4mm ≥ 400 was clinically suitable in Japanese patients. No surrogate maker for a high-risk LRP was found; consequently, direct intravascular evaluation of plaque characteristics remains important.

Keywords: ACS, acute coronary syndrome; Asian; CI, confidence interval; CKD, chronic kidney disease; IL-6, interleukin-6; IQR, interquartile range; IVUS, intravascular ultrasound; Intracoronary imaging; LCBI; LCBI, lipid core burden index; LDL-C, low-density lipoprotein cholesterol; LRP, lipid-rich plaque; Lipid core burden index; MDA-LDL, malondialdehyde-modified LDL; MLA, minimum lumen area; NIRS; NIRS, near infrared spectroscopy; NSTE-ACS, non-ST elevation acute coronary syndrome; OR, odds ratio; PCI, percutaneous coronary intervention; PCSK9, proprotein convertase subtilisin / kexin type 9; SA, stable angina; STEMI, ST-elevation myocardial infarction; TNF-α, tumor necrosis factor-α; Vulnerable plaque; hs-CRP, high-sensitive C reactive protein.