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

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.