acute coronary syndrome and tend not to have full occlusion of a coronary artery. If there is evidence of myocardial cell death (especially elevated cardiac biomarkers) they are considered to have a non-ST-elevation myocardial infarction (NSTEMI); otherwise they are classified with unstable angina. Their management is based on the estimation of their risk for adverse events. Patients at low risk can be adequately treated with medical therapy, in many ways similar to the one used for STEMI (but excluding thrombolytics). Those at moderate to high risk benefit from an early invasive strategy, which includes coronary angiography and, if necessary, revascularization with percutaneous coronary intervention or coronary artery bypass surgery. Medical therapy for acute coronary syndromes is based on drugs that act against ischemia and resultant angina and limit the infarct size (i.e., the area of myocardium that is affected), as well as drugs that inhibit clot formation. The latter include antiplatelet agents, which block the activation and aggregation of platelets (cellular blood components that contribute to clot formation), and anticoagulant agents (which attenuate the coagulation cascade). Long-term therapy in acute coronary syndrome survivors is targeted against recurrence and long-term complications (secondary prevention). Women are taken less seriously than men when they have a heart attack leading to higher mortality among women. Patient-dependent initial measures Because of the relationship between the duration of myocardial ischemia and the extent of damage to heart muscle, public health services encourage people experiencing possible acute coronary syndrome symptoms or those around them to immediately call emergency medical services. Patients with known coronary artery disease who have been prescribed nitroglycerin should promptly take one dose, and call emergency medical services if their symptoms do not improve within 2–5 minutes. Patients should not be transported to hospital by private vehicles instead of an ambulance, unless evacuation by land or air ambulance is impossible (e.g., dangerous weather in a very remote area), and if they must be, it should be done if possible with someone trained in cardiac first aid. Chewing non−enteric-coated aspirin is encouraged (unless there are contraindications). Health care professionals are responsible for teaching their patients at risk of acute coronary syndrome what the symptoms of this condition are, and that it is imperative to seek urgent medical attention in case they present. Emergency services Emergency Medical Services (EMS) Systems vary considerably in their ability to evaluate and treat patients with suspected acute myocardial infarction. Some