Cardiology is a medical specialization which deals with the diagnostics and treatment of diseases of the heart and cardiovascular system. The most common diseases group in that field includes: coronary artery disease (primarily due to atherosclerosis of the coronary arteries feeding the heart), myocardial infarction, hypertension, heart failure, atrial fibrillation. In addition, cardiologist treats congenital heart disease, valvular defects, cardiomyopathies, arrhythmias, and many other diseases related to the heart and  cardiologist work.

Cardiologists have extensive knowledge of internal medicine, which is invaluable to the management of patients with other diseases associated with heart disease, such as diabetes, hypercholesterolemia, or kidney disease, which often have a very significant impact on the course of the disease. They order and carry out a number of specialized studies: electrocardiography (ECG), echocardiography – the ultrasound (ECHO), heart rate, exercise tests, coronary angiography, 24-hour ECG or blood pressure (Holter).