Abstract 9933: Determinants of High-Risk Featured Coronary Plaque Burden for the Prediction of Patient Outcomes in Suspected Coronary Artery Disease: A Coronary Ct Angiography Study

Abstract

Background: Computed tomography (CT) coronary angiography (CCTA) is a non-invasive imaging modality that provides quantitative assessment of disease burden of coronary atherosclerosis and epicardial adipose tissue (EAT). This study aimed to investigate the prognostic implication of low-attenuation non-calcified plaque (LAP) burden and its association with EAT in patients with suspected coronary artery disease (CAD). Methods: This study consists of 400 symptomatic patients (58% male, 65 years) with suspected CAD undergoing CCTA. Coronary artery calcium score (CACS) was measured with Agatston method. LAP was defined as an atherosclerotic plaque with CT attenuation value of <30 Hounsfield Units (HU). The %LAP was calculated as LAP volume divided by vessel volume(%). EAT volume was defined as adipose tissues having CT attenuation value ranging from -250 to -30 HU within pericardial sac. The primary endpoint was a composite event of death and coronary revascularization. Results: Among the study patients, quartiles for %LAP for 3-vessel coronary arteries were as follow; Q1 0.06-0.72%, Q2 0.72-1.11%, Q3 1.11-1.71%, and Q4>1.74%. During the follow-up period (median 552 days), the primary endpoint was observed in 52 patients (13%). In the Cox hazard model, %LAP (Q4) [HR 2.16, p<0.05], obstructive CAD >50% diameter stenosis [HR 9.44, p<0.05], and diabetes mellitus [HR 1.78, p<0.05] were independent predictors of the primary endpoint. Kaplan-Meier curves analysis demonstrated that patients with %LAP (Q4) had a worse prognosis compared to those with Q1-Q3 (p<0.001, Figure 1). In logistic regression analysis adjusting for age, gender, and clinical variables, the determinants of %LAP (Q4) were a greater CACS and EAT volume (p<0.05). Conclusions: This study demonstrates that CACS and EAT volume provide noninvasive stratification of patients who exhibit a greater high-risk coronary plaque burden that may contribute to acute coronary events.