Background:It has been shown that administration of statins reduced the risk of peri-procedural myocardial damage.However,it remains unclear whether Chinese medicine Danlou Tablet(丹蒌片),similar to statins,may protect patients undergoing percutaneous coronary intervention(PCI)from peri-procedural myocardial damage.Objective:To demonstrate the hypothesis whether treatment with Danlou Tablet would improve clinical outcome in patients undergoing selective PCI with non-ST elevation acute coronary syndrome(NSTE-ACS)in China.Methods:Approximately 220 patients with unstable angina or non-ST-segment elevation myocardial infarction undergoing PCI will be enrolled and randomized to Danlou Tablet treatment(4.5 g/day for 2 days before intervention,with a further 4.5 g/day for 90 days thereafter)or placebo.All patients will not receive Danlou Tablet before procedure.The primary end point is to evaluate the incidence of cardiac death,myocardial infarction or unplanned re-hospitalization and revascularization after 30 days in patients undergoing selective PCI treated with Danlou Tablet compared with placebo.Secondary endpoints include the incidence of peri-procedural myocardial injury,3-month clinical outcomes,the quality of life and Chinese medicine syndromes assessment.Conclusion:This study protocol will provide important evidence of Danlou Tablet treatment on the peri-procedural myocardial injury in patients with NSTE-ACS undergoing selective PCI,which may support a strategy of routine Danlou Tablet therapy to improve the clinical outcomes.