Acute and chronic ischaemic diseases are among the main death reasons and civilized world menace. Branched chain amino acids (BCAAs): valine (Val), leucine (Leu), and isoleucine (Ile) are the main source of nitrogen to glutamine (Gln) and alanine (Ala) synthesis in muscles. In numerous cachexy-producing illnesses such as cancer, sepsis, diverse injuries and heart diseases increased consumption of BCAAs occurs. In myocardial ischemia BCAAs derived from the mobilization of muscle protein may be an important alternative energy substrate for the heart. BCAAs are oxidative energy substrates for the heart and may exert anabolic effects on myocardial protein (8). The aim of our study was to determine branched chain amino acids (BCAAs) concentrations in blood plasma of patients with chronic and acute ischeamic heart disease and to find out changes that those amino acids undergo during the first five days of patients' hospitalization.