Differences in plaque composition and distribution in stable coronary artery disease versus acute coronary syndromes; non‐invasive evaluation with multi‐slice computed tomography

Abstract

Background: Plaque composition rather than degree of luminal narrowing may be predictive of acute coronary syndromes (ACS). The purpose of the study was to compare plaque composition and distribution with multi‐slice computed tomography (MSCT) between patients presenting with either stable coronary artery disease (CAD) or ACS. Methods: MSCT was performed in 22 and 24 patients presenting with ACS or stable CAD, respectively. Coronary lesions were classified as calcified, non‐calcified or mixed while signal intensity (SI) was measured. Results: In patients with stable CAD, the majority of lesions were calcified (89%). In patients with ACS, less calcifications were observed with a greater proportion of non‐calcified (18%) or mixed (36%) lesions (P<0.001). Accordingly, mean SI of plaques was significantly less in ACS (320±201 HU versus 620±256 HU in stable CAD, P<0.001). Dividing lesions in the ACS group according to culprit versus non‐culprit vessel location resulted in no significant difference in average SI between these two groups while still lower as compared to stable CAD (P<0.001). Conclusions: In patients with ACS, significantly less calcifications were present as compared to stable CAD. Moreover, even in non‐culprit vessels, multiple non‐calcified plaques were detected, indicating diffuse rather than focal atherosclerosis in ACS.

• Acute coronary syndrome
• computed tomography