 This is a prospective, open-label, parallel group study to evaluate the efficacy of rosuvastatin 10mgd or 20mgd on critical coronary atherosclerosis in Chinese ACS patients. The anticipated duration of the study is approximately 36 weeks, Patients with angiographic luminal diameter narrowing in any non-culprit site between 40-70 will be enrolled from the study site. The primary efficacy parameter is the percent change of Total Atheroma Volume TAV of critical coronary atherosclerosis after 36 weeks of treatment. 