Coronary Plaque Morphology and the Anti-Inflammatory Impact of Atorvastatin: A Multicenter 18F-Fluorodeoxyglucose Positron Emission Tomographic/Computed Tomographic Study.

Abstract

$\textbf{Background:}$ Non-obstructive coronary plaques manifesting higher-risk morphology (HRM) associate with an increased risk of adverse clinical cardiovascular events. We sought to test the hypothesis that statins have a greater anti-inflammatory effect within coronary plaques containing HRM.

$\textbf{Methods:}$ In this prospective multicenter study, 55 subjects with or at high risk for atherosclerosis underwent $^{18}$F-fluorodeoxyglucose-positron emission tomography/ computed tomography (FDG-PET/CT) imaging at baseline and after 12 weeks of treatment with atorvastatin. Coronary arterial inflammation (FDG uptake, expressed as target-to-background ratio [TBR]) was assessed in the left main coronary artery (LMCA). While blinded to the PET findings, contrast-enhanced CT angiography (CTA) was performed to characterize the presence of HRM (defined as non-calcified or partially-calcified plaques) in the LMCA.

$\textbf{Results:}$ Arterial inflammation (TBR) was higher in LMCA segments with- vs. without- HRM (mean ± SEM: 1.95±0.43 vs. 1.67±0.32, LMCA with- vs. without HRM, p=0.04). Moreover, atorvastatin treatment for 12 weeks reduced TBR more in LMCA segments with- vs without-HRM (12 week-baseline ΔTBR [95% CI]: -0.18 [-0.35, -0.004] vs. 0.09 [-0.06, 0.26], p=0.02). Furthermore, this relationship between coronary plaque morphology and change in LMCA inflammatory activity remained significant after adjusting for baseline LDL and statin dose ($\beta$=-0.27, p=0.038).

$\textbf{Conclusions:}$ In this first study to evaluate the impact of statins on coronary inflammation, we observed that the anti-inflammatory impact of statins is substantially greater within coronary plaques that contain higher-risk morphological features. These findings suggest an additional mechanism by which statins disproportionately benefit individuals with more advanced atherosclerotic disease.