Observational Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Cardiol. Aug 26, 2016; 8(8): 481-487
Published online Aug 26, 2016. doi: 10.4330/wjc.v8.i8.481
Relationship between coronary calcium score and high-risk plaque/significant stenosis
Kohichiro Iwasaki, Takeshi Matsumoto
Kohichiro Iwasaki, Takeshi Matsumoto, Department of Cardiology, Okayama Kyokuto Hospital, Okayama 703-8265, Japan
Author contributions: All the authors contributed to this manuscript.
Institutional review board statement: The study was reviewed and approved by the Institutional Review Board of Okayama Kyokuto Hospital.
Informed consent statement: All study participants provided informed consent prior to study enrollment.
Conflict-of-interest statement: The authors declare that there is no conflict of interest.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Kohichiro Iwasaki, MD, Department of Cardiology, Okayama Kyokuto Hospital, 567-1, Kurata, Naka-ku, Okayama 703-8265, Japan. kiwasaki@kyokuto.or.jp
Telephone: +81-86-2763231 Fax: +81-86-2741028
Received: April 13, 2016
Peer-review started: May 26, 2016
First decision: June 16, 2016
Revised: June 29, 2016
Accepted: July 14, 2016
Article in press: July 18, 2016
Published online: August 26, 2016
Processing time: 88 Days and 23.2 Hours
Abstract
AIM

To investigate the relationship between coronary calcium score (CCS) and vulnerable plaque/significant stenosis using coronary computed tomographic angiography (CCTA).

METHODS

CCTA was performed in 651 patients and these patients were divided into the four groups (CCS 0, 1-100, 101-400 and > 400). We studied the incidence of high-risk plaque, including positive remodeling, low attenuation plaque, spotty calcification, and napkin-ring sign, and significant stenosis in each group.

RESULTS

High-risk plaque was found in 1.3%, 10.1%, 13.3% and 13.4% of patients with CCS 0, 1-100, 101-400 and > 400, respectively (P < 0.001). The difference was only significant for patients with zero CCS. The incidence of significant stenosis was 0.6%, 7.6%, 13.3% and 26.9% for each patient group, respectively (P < 0.001), which represented a significant stepwise increase as CCS increased. The combined incidence of high-risk plaque and significant stenosis was 1.9%, 17.7%, 26.9% and 40.3% in each patient group, respectively (P < 0.001), again representing a significant stepwise increase with CCS. The rate of major coronary event was 0%, 4.0%, 7.9% and 17.2% in each patient group, respectively (P < 0.001), another significant stepwise increase as CCS increased.

CONCLUSION

Stepwise increased risk of coronary events associated with increasing CCS is caused by increasing incidence of significant stenosis, while that of high-risk plaque remains the same.

Keywords: Coronary calcium score; Coronary stenosis; High-risk plaque; Low attenuation plaque; Napkin-ring sign; Positive remodeling; Spotty calcification

Core tip: Coronary computed tomographic angiography was performed in 651 patients and these patients were divided into the four groups according to coronary calcium score (CCS): 0, 1-100, 101-400 and > 400. The incidence of high-risk plaque was not significantly different among the three groups, except patients with zero CCS. The incidence of significant stenosis increased stepwise as CCS increased, as did the rate of major coronary event. Therefore, the stepwise increased risk of coronary events associated with increasing CCS is caused by an increasing incidence of significant stenosis, while that of high-risk plaque remains the same.