Acute Effects of Statin Therapy on Coronary Atherosclerosis Following an Acute Coronary Syndrome

No data exist on the acute effects of statin therapy on human coronary atherosclerotic plaques. The objective of our study was to evaluate the early (<2 months) effects of newly initiated statin therapy on coronary atherosclerosis as evaluated by intravascular ultrasonography. The study population consisted of 74 patients (mean age 58 ± 8 years) who had been included in the ERASE trial (evaluating the effects of reconstituted high-density lipoprotein infusions). All patients underwent serial intravascular ultrasonographic (IVUS) evaluation at baseline (3 ± 2 days after an acute coronary syndrome [ACS]) and after 6 ± 1 weeks of follow-up. Statin therapy was initiated after ACS in 36 patients who received ≤1 dose of statins before baseline IVUS examination (newly initiated statin therapy group), and 38 patients were already on a stable statin dose before the ACS (long-term statin therapy group). Atorvastatin at a dose of 40 mg/day was the most common regimen in the 2 groups. Percent changes in atheroma volume (prespecified primary efficacy parameter) were −4.71 ± 0.96% in the newly initiated statin therapy group (p <0.0001) and −0.54 ± 0.89% in the long-term statin therapy group (p = 0.546; p = 0.002 for comparison between groups). Median nominal changes in atheroma volume were −9.10 mm³ (interquartile range −12.56 to −3.73, p <0.0001 vs baseline) and 1.21 mm³ (interquartile range −6.41 to 3.76, p = 0.429 vs baseline) in the newly initiated and long-term statin therapy groups, respectively (p = 0.003 for comparison between groups). Greater decreases in total cholesterol (r = 0.25, p = 0.035), ratio of total to high-density lipoprotein cholesterol (r = 0.28, p = 0.018), and high-sensitivity C-reactive protein (r = 0.31, p = 0.046, for patients with high-sensitivity C-reactive protein measurements within 7 days after IVUS examination) were associated with larger percent changes in atheroma volume. In conclusion, newly initiated statin therapy is associated with rapid regression of coronary atherosclerosis within 2 months. This effect was in part associated with decreases in atherogenic lipid and inflammatory parameters. These results provide insight into the rapid clinical benefits of statin therapy after an ACS.