Quantitative plaque characterisation and association with acute coronary syndrome on medium to long term follow up: insights from computed tomography coronary angiography

Ravi K Munnur; Kevin Cheng; Jordan Laggoune; Andrew Talman; Rahul Muthalaly; Nitesh Nerlekar; Yi-Wei Baey; Jason Nogic; Andrew Lin; James D Cameron; Sujith Seneviratne; Dennis T L Wong

doi:10.21037/cdt-21-763

Quantitative plaque characterisation and association with acute coronary syndrome on medium to long term follow up: insights from computed tomography coronary angiography

Cardiovasc Diagn Ther. 2022 Aug;12(4):415-425. doi: 10.21037/cdt-21-763.

Authors

Affiliations

¹ Monash Cardiovascular Research Centre, Department of Medicine (Monash Medical Centre) Monash University and Monash Heart, Monash Health, Clayton, VIC, Australia.
² South Australian Health Medical Research Institute (SAHMRI), Adelaide, Australia.

Abstract

Background: Computed tomography coronary angiography (CTCA) is an established imaging modality widely used for diagnosing coronary artery stenosis with expanding potential for comprehensive assessment of coronary artery disease (CAD). Lesion-based analyses of high-risk plaques (HRP) on CTCA may aid further in prognostication presenting with stable chest pain. We conduct qualitative and quantitative assessments to identify HRPs that are associated with acute coronary syndrome (ACS) on a medium to long term follow-up.

Methods: Retrospective cohort study of patients who underwent CTCA for suspected CAD. Obstructive stenosis (OS) is defined as ≥50% and the presence of HRP and its constituents: positive-remodelling (PR), low-attenuation-plaque (LAP; <56 HU), very-low-attenuation-plaque (vLAP; <30 HU) and spotty-calcification (SC) were recorded. A cross-sectional quantitative analysis of HRP was performed at the site of minimum-luminal-area (MLA). The primary endpoint was fatal or non-fatal ACS on follow-up.

Results: A total of 1,257 patients were included (mean age 61±14 years old and 51% male) with a median follow-up of 7.24 years (interquartile range 5.5 to 7.7 years). The occurrence of ACS was significantly higher in HRP (+) patients compared to HRP (-) patients and patients with no plaques (20.5% vs. 1.6% vs. 0.4%, log-rank test P<0.001). ACS was more frequent in HRP (+)/OS (+) patients (20.7%) compared to HRP (+)/OS (-) patients (8.6%), HRP (-)/OS (+) patients (1.8%) and HRP (-)/OS (-) patients (1.0%). OS, cross-sectional plaque area (PA) and the presence of vLAP identified those HRP lesions that were more likely to cause future ACS. Cross-sectional LAP area (<56 HU) in HRP lesions added incremental prognostic value to OS in predicting ACS (P=0.008).

Conclusions: The presence of OS and the LAP area at the site of MLA identify the HRP lesions that have the greatest association with development of future ACS.

Keywords: Coronary artery disease (CAD); acute coronary syndrome (ACS); computed tomography coronary angiography (CTCA); high-risk plaque (HRP).