Effect of Nicorandil for the Patients of Acute ST Segment Elevation Myocardial Infarction

Effect of Early Administration of Intracoronary Nicorandil Via Thrombus Aspiration Catheter Device During Primary Percutaneous Coronary Intervention for the Patients of Acute ST Segment Elevation Myocardial Infarction

To evaluate whether nicorandil as an adjunctive therapy for acute myocardial infarction (AMI) reduces reperfusion injury.

Reperfusion injury might occur in patients with acute ST segment elevation myocardial infarction undergoing the primary percutaneous coronary intervention(P-PCI),characterized by myocardial stunning, reperfusion-induced arrhythmia, microvascular dysfunction and myocardial cellular apoptosis, etc.

Nicorandil is an antianginal agent with a dual mechanism of action: nitrate and K+ATP channel opener. The nitrate action causes vasodilation of systemic veins and epicardial coronary arteries, while the adenosine triphosphate (ATP)-sensitive potassium channel opener action causes vasodilation of peripheral and coronary resistance arterioles. Nicorandil not only decreases preload and afterload but also increases coronary blood flow.

The study will compare the effectiveness between nicorandil and placebo of preventing the reperfusion injury and left ventricle remodeling in patients with acute ST segment elevation myocardial infarction undergoing the P-PCI.It is intended that before reperfusion injury ,nicorandil which was early used by intracoronary injection could prevent and release the microcirculatory spasm, release the coronary microvascular endothelial swelling,decrease embolism of atherosclerotic debris and thrombus formation.So,it could decrease the phenomenon of no-reflow/slow reflow,reperfusion-induced arrhythmia and worsening of chest pain.

Inclusion Criteria:

• Acute ST Segment Elevation Myocardial Infarction (ASTEMI) defined as typical chest pain lasting >30min within the previous 12 h, with a clear ST-segment elevation of >0.1millivolt(mV) in ≥2 contiguous electrocardiographic leads, and the value of troponin I(TNI) above the maximum peak in the normal range.
• Age20-80,All genders
• The first myocardial infarction, and there is no history of PCI therapy and coronary artery bypass grafting
• The infarct-related artery(IRA) is totally occlusive
• Blood pressure is higher than 90/60 millimeters of mercury（mmHg）
• The time from myocardial infarction onset to reach the hospital is less than 12 hs
• Successful interventional treatment, the residual stenosis of IRA is less than 30% ,
• TIMI flow grade 3

Exclusion Criteria:

• kidney dysfunction (creatinine >2 mg/dl),
• History of previous liver disease,
• Cardiogenic shock,
• History of myocardial infarction (MI)
• History of coronary artery bypass grafting
• History of allergic response to drugs
• Right ventricular infarction
• Severe hypovolemia