Acute coronary syndrome occurs due to a sudden decrease in flow in the coronary arteries, and as a result, severe ischemia of the affected part of the heart muscle develops. Acute coronary syndrome includes unstable angina pectoris, myocardial infarction without ST segment elevation, and myocardial infarction with ST segment elevation in the electrocardiogram. Given that these are high-risk patients who require immediate treatment, early recognition and treatment are extremely important. Emergency medical service is an integral part of the care of these patients. The aim of this paper is to describe hypoxic damage to the heart and its division, and the concept of acute myocardial infarction with and without ST junction elevation will be explained, as well as the concept of angina pectoris. The paper will also describe the anatomy and physiology of the heart and the electrocardiogram as a basic diagnostic indicator. As an important factor, the paper will describe the approach of the emergency medical aid team to the patient and the way of treating the patient at the scene and during transport to the hospital. The paper will present statistical data on interventions related to acute coronary syndrome from the "eHitna" program database in the period from 2019-2021. years.