LAUSR

It is still debatable whether the so-called high-risk plaque (HRP) simply represents a certain phase during the natural history of coronary atherosclerotic plaques or the disease progression would differ according to the presence of HRP. We determined whether the pattern of non-obstructive lesion progression into obstructive lesions would differ according to the presence of HRP. Patients with non-obstructive coronary artery disease, defined as % diameter stenosis (%DS) ≥50%, were enrolled from a prospective, multinational registry of consecutive patients who underwent serial coronary computed tomography angiography at an inter-scan interval of ≥2 years. HRP was defined as lesions with ≥2 of positive remodelling, spotty calcification, and low-attenuation plaque. The total and compositional percent atheroma volume (PAV) at baseline and annualized PAV change were compared between non-HRP and HRP lesions. A total of 1,115 non-obstructive lesions were identified from 327 patients (61.1±8.9 years old, 66.0% male). There were 690 non-HRP and 425 HRP lesions. HRP lesions possessed greater PAV and %DS at baseline compared to non-HRP lesions. However, the annualized total and non-calcified PAV change were greater in non-HRP lesions than in HRP lesions. On multivariate analysis, addition of baseline PAV and %DS to clinical risk factors improved the predictive power of the model (Table). When clinical risk factors, PAV, %DS, and HRP were all adjusted on Model 3, only baseline PAV and %DS independently predicted the development of obstructive lesions (hazard ratio (HR) 1.046 [95% confidence interval (CI): 1.026–1.066] and HR 1.087 [95% CI: 1.055–1.119], respectively, all p<0.001), while HRP did not (p>0.05). Comparison of C-statistics of per-lesion analysis to predict progression to obstructive lesion C-statistics (95% CI) P Model 1: Baseline PAV 0.880 (0.879–0.884) – Model 2: Model 1 + baseline %DS 0.938 (0.937–0.939) vs. Model 1: <0.001 Model 3: Model 2 + HRP 0.935 (0.934–0.937) vs. Model 2: 0.004 Adjusted for age, male sex, hypertension, diabetes mellitus, hyperlipidemia, family history of coronary artery disease, smoking, body mass index, and statin use. The pattern of individual coronary atherosclerotic plaque progression differed according to the presence of HRP. Baseline PAV was the most important predictor for lesions developing into obstructive lesions rather than the presence of HRP features at baseline. This work was supported by the National Research Foundation of Korea funded by the Ministry of Science and ICT (Grant No. 2012027176).