EPIDEMIOLOGYThe leading cause of death in the United States is coronary heart disease. An estimated 15.4 million Americans have coronary heart disease, making them seven times more likely to suffer a heart attack than the general population(1). The annual incidence of myocardial infarction is estimated at 715,000, of which approximately 29% are ST-segment elevation MI (STEMI)(1). It is important to note that the mortality rate from STEMI has decreased over the years; however, there is still a considerable proportion of eligible STEMI patients who do not receive any form of reperfusion therapy. In an analysis of 10,954 STEMI patients enrolled in the Global Acute Coronary Events Registry, it was found that 33% of eligible patients did not receive any reperfusion therapy(2).PATHOPHYSIOLOGYUnder normal conditions, the coronary arteries deliver blood oxygenated to the myocardium in order to meet the oxygen needs of the heart muscle supplied by these arteries. In patients with coronary atherosclerosis, atherosclerotic plaque develops in the lumen of the coronary artery. When this plaque becomes vulnerable, its fibrous cap can rupture and stimulate platelet aggregation and thrombus formation(3). An occlusive thrombus forms and impedes blood flow in the coronary artery, thus leading to ischemia of the myocardium supplied by this artery. Evidence of this ischemia is reflected on the electrocardiogram as ST segment elevation. Due to lack of blood flow and oxygen supply, cardiac myocytes begin to die in a wave-like manner, from the endocardium to the epicardium, over several hours(3). Restoration of blood flow through the blocked coronary artery must occur quickly to prevent the formation of a large infarct. CLINICAL PRESENATION The most typical presentation of an acute myocardial infarction is chest pain. It is often described as a squeezing or crushing feeling in the central part of the chest. Unlike angina, chest pain due to myocardial infarction persists at rest and is generally not relieved by nitroglycerin (4). The pain frequently radiates to the shoulder, arm, neck, jaw, or back. However, some heart attack patients may not have any chest pain. A retrospective secondary analysis of 2,541 patients with cardiac ischemia found that women (P = 0.007), diabetics (P = 0.01), and older patients (P = 0.0001) were less likely to have cardiac ischemia. classic chest pain (5). . They may experience some of the associated symptoms, including nausea and vomiting, cold sweats, dizziness, shortness of breath, or feeling weak or apprehensive (4). Physical examination findings of patients with acute myocardial infarction vary widely.