Objective: To investigate mechanism on the restenosis after percutaneous transluminal coronary angioplasty (PTCA) with FSZ (Hirudo, Rhizoma Coptidis, Radix et Rhizoma Rhei, Radix Curcumae, Rhizoma Polygonati Odoroti, etc) by studying the protective effects of FSZ on arrhythmia and injury induced by ischemia and reperfusion.Methods:Rats were randomly divided into four groups and administered orally with FSZ. Left coronary artery ligature was used to form ischemia and reperfusion model. Lipid peroxidation (LPO), superoxide dismutase (SOD), cyclic adenosine monophosphate (cAMP), area of myocardial infarction, myocyte ultrastructural injury and occurrence of arrhymia were investigated.Results: FSZ could improve the changes in ST segment. In rats treated with FSZ, the levels of SOD were elevated while cAMP, LPO, and the specific viscosity of whole blood or plasma and the aggregation of the platelet were lowered, keep to improving the hemorheological changes. It also could antagonize the myocardial damage by myocardial ischemia or reperfusion reduced the area of myocardial infarction. Especially, Fufangshuizhijing Capsule reduced the area of left ventricular (LV) compared with the control group remarkably.Conclusion: FSZ could obviously antagonize arrhythmia and the injury induced by the ischemia and reperfusion, FSZ may scavenge oxygen free radical, regulate the second messenger, remarkably improve the local circulation to reduce the specific viscosity of whole blood of plasma and the aggregation of the platelet in rats, protect mitochondria safeguard the cardiac myocyte to treat PTCA.