What Do We Get from Recent Statin and CETP Inhibitors Trials?

Recent clinical trials and meta-analyses have indicated that high-intensive statin treatment lowers low-density lipoprotein cholesterol (LDL-C) levels and reduces the risk of nonfatal cardiovascular (CV) events compared with moderate-intensity statin treatment. However, there are residual risks of CV events and safety concerns associated with high-intensity statin treatment. The Improved Reduction of Outcomes: Vytorin Efficacy International Trial (IMPROVE-IT) study showed that ezetimibe plus moderate-intensity statin therapy after acute coronary syndromes incrementally lowers LDL-C levels and improved CV outcomes compared with moderate-intensity statin therapy. However, despite the LDL-C-lowering effects, a substantial residual CV risk still remains, which includes other lipid abnormalities such as low high-density lipoprotein cholesterol (HDL-C). The most representative agents that primarily increase HDL-C are cholesteryl ester transfer protein (CETP) inhibitors. Until now, 4 CETP inhibitors, including torcetrapib, dalcetrapib, evacetrapib, and anacetrapib, have been introduced and all have significantly raised the HDL-C from 30% to 133%. However, the results for CV outcomes in clinical trials differed, based on the 4 agents. Torcetrapib increased the risk of CV events and total mortality in patients at high CV risk (ILLUMINATE trial). Dalcetrapib and evacetrapib did not result in lower rate of CV events in patients with recent acute coronary syndrome and high risk vascular disease, respectively (dal-OUTCOMES and ACCELERATE trials). However, anacetrapib significantly decreased the incidence of major coronary events in patients with atherosclerotic vascular disease (REVEAL trial). This topic summarizes the major results of recent statin and CETP inhibitor trials and provides framework to interpret and implement the trial results in real clinical practice.

Early Effects of Intensive Lipid-Lowering Treatment on Plaque Characteristics Assessed by Virtual Histology Intravascular Ultrasound

PURPOSE: The effects of short-term intensive lipid-lowering treatment on coronary plaque composition have not yet been sufficiently evaluated. We investigated the influence of short-term intensive lipid-lowering treatment on quantitative and qualitative changes in plaque components of non-culprit lesions in patients with acute coronary syndrome. MATERIALS AND METHODS: This was a prospective, randomized, open-label, single-center trial. Seventy patients who underwent both baseline and three-month follow-up virtual histology intravascular ultrasound were randomly assigned to either an intensive lipid-lowering treatment group (ezetimibe/simvastatin 10/40 mg, n=34) or a control statin treatment group (pravastatin 20 mg, n=36). Using virtual histology intravascular ultrasound, plaque was characterized as fibrous, fibro-fatty, dense calcium, or necrotic core. Changes in plaque components during the three-month lipid-lowering treatment were compared between the two groups. RESULTS: Compared with the control statin treatment group, there was a significant reduction in low-density lipoprotein cholesterol in the intensive lipid-lowering treatment group (-20.4±17.1 mg/dL vs. -36.8±17.4 mg/dL, respectively; p<0.001). There were no statistically significant differences in baseline, three-month follow-up, or serial changes of gray-scale intravascular ultrasound parameters between the two groups. The absolute volume of fibro-fatty plaque was significantly reduced in the intensive lipid-lowering treatment group compared with the control group (-1.5±3.4 mm3 vs. 0.8±4.7 mm3, respectively; p=0.024). A linear correlation was found between changes in low-density lipoprotein cholesterol levels and changes in the absolute volumes of fibro-fatty plaque (p<0.001, R2=0.209). CONCLUSION: Modification of coronary plaque may be attainable after only three months of intensive lipid-lowering treatment.