Cardiovascular diseases are the primary death factors of people in the world. Myocardial infarctions and strokes are the most predominant among them. Securing a patient with myocardial infarction requires a rapid pre-hospital procedure and a fast cardiac intervention at an invasive cardiology centre. The paper describes a case of a 55-year-old man diagnosed with acute coronary syndrome with ST-segment elevation myocardial infarction (STEMI), i.e. myocardial infarction of the bottom wall. The operative procedure requires following the MONA algorithm (M – morphine, O – oxygen, N – nitroglycerin, A – aspirin). The process of data tele-transmission is an important element of the pre-hospital proceedings at the level of Medical Emergency Team. It makes it possible to send quickly the ECG record from the ambulance or patient’s home to a cardiology centre.