Effect of combination of ezetimibe and a statin on coronary plaque regression in patients with acute coronary syndrome : ZEUS trial (eZEtimibe Ultrasound Study)

BackgroundMany trials have shown that statins can reduce plaque volume (PV) associated with the degree of LDL-C reduction.The goal of this study is to determine whether the combination of ezetimibe and a statin produces greater reductions in coronary plaque volume compared to statin monotherapy in patients with acute coronary syndrome (ACS).MethodsProspective serial intravascular ultrasound (IVUS) of non-culprit lesions of the target vessel was performed in 95 patients with ACS. Of these, 50 patients were administered combination of atorvastatin 20 mg/day and ezetimibe 10 mg/day. 45 subjects treated by atorvastatin 20 mg/day alone were the control group. At the beginning and 24 weeks after PCI, quantitative PV was accessed by IVUS. The primary end point was the percentage change in non-culprit coronary PV.ResultsLDL-C was significantly decreased by 49.8% in the ezetimibe/atorvastatin group compared with 34.6% in the atorvastatin group. Significant regression of plaque volume was observed from baseline to follow-up in both groups. The percentage changes in PV were greater in the ezetimibe/atorvastatin group than in the atorvastatin alone group (12.5% versus 7.6%, p = 0.06), but statistically not significant. In 34 diabetic patients, regression of PV was significantly greater in the ezetimibe/atorvastatin group than in the statin alone group (13.9% versus 5.1%, p = 0.04) and % change of PV significantly correlated with LDL-C reduction.ConclusionsAdditional LDL-C reduction with combination therapy tended to reduce more plaque regression compared to a statin alone in patients with ACS. In diabetic patients, further reduction of LDL-C was associated with a significantly greater reduction in PV.