Bridging the gap for lipid lowering therapy: plaque regression, coronary computed tomographic angiography, and imaging-guided personalized medicine

Abstract

Lipid-lowering therapy effectively decreases cardiovascular risk on a population level, but it remains difficult to identify an individual patient's personal risk reduction while following guideline directed medical therapy, leading to overtreatment in some patients and cardiovascular events in others. Recent improvements in cardiac CT technology provide the ability to directly assess an individual's atherosclerotic disease burden, which has the potential to personalize risk assessment for lipid-lowering therapy. Areas covered: We review the current unmet need in identifying patients at elevated residual risk despite guideline directed medical therapy, the evidence behind plaque regression as a potential marker of therapeutic response, and highlight state-of-the-art advances in coronary computed tomographic angiography (CCTA) for measurement of quantitative and qualitative changes in coronary atherosclerosis over time. Literature search was performed using PubMed and Google Scholar for literature relevant to statin therapy and residual risk, coronary plaque regression measurement, and CCTA assessment of quantitative and qualitative change in coronary atherosclerosis. Expert commentary: We discuss the potential ability of CCTA to guide lipid-lowering therapy as a bridge between population and personalized medicine in the future, as well as the potential barriers to its use.

Keywords: Cardiac computed tomography; PCSK-9; coronary atherosclerosis; coronary computed tomographic angiography; lipid-lowering therapy; personalized medicine; plaque regression; statin.

Figure 1.

72 year-old asymptomatic male with hyperlipidemia and a 10-year ASCVD risk, estimated with the Pooled Cohort Equations of 7.5%. A. CCTA images of the left circumflex artery showing mild atherosclerotic plaque (arrow). B, C: Multiple views of the proximal left circumflex artery showing small, proximal plaque (arrows). The patient was treated with 10 mg of atorvastatin. Eight years later, he presented with myocardial infarction due to high-grade stenosis in the same arterial distribution of the left circumflex artery.

Figure 2.

63 year-old asymptomatic male referred for coronary CT assessment. A. Volume rendering of the coronary arteries. B. A small eccentric plaque (arrow) with calcified and non-calcified components is seen on detailed image of the left anterior descending artery.

Figure 3.

75 year-old female with a 10-year ASCVD risk estimated by the Pooled Cohort Equations of 18%. No coronary artery disease was present on CCTA. A. Images of the left anterior descending coronary artery. B. Cross-section images of the left anterior descending coronary artery.

Figure 4.

68 year-old male with a 10-year ASCVD risk estimated by the Pooled Cohort Equations of 5%. Images of the left coronary artery. A. Longitudinal and B. cross-sectional views show a small plaque that is predominantly calcified.

Figure 5.

48 year-old male with elevated total cholesterol referred for coronary artery screening by CCTA. A. Longitudinal view of the left anterior coronary artery shows a large soft plaque in the mid artery. B. Cross section views of the same plaque show eccentric soft plaque surrounding the cross section of the coronary artery.