The aim of the study was to increase the efficiency of treatment of patients with Acute Miocardial Infarction by incorporating the protocol therapy for the course of parenteral use of L-arginine and L-carnitine.Material and methods.A total of 45 patients with acute coronary syndrome with ST segment elevation were investigated, who had undergone urgent balloon angioplasty and stenting of a heart attack-dependent coronary artery. The study selected patients aged on average (59,57 ± 8,07) years. The experimental group consisted of 30 patients, who received standard protocol treatment of ACS (MI) and additionally were prescribed 4.2 g L-arginine and 2.0 g L-carnitine in the 100 ml solution for infusion once daily for 5 days intravenously. The control group included 15 patients with ACS (MI) who also had percutaneous coronary intervention, but this group received only standard protocol treatment.In addition to general clinical, instrumental and laboratory methods (general blood test, MB Creatinephosphokinase fraction (CFC-MB), Troponin T, oxygen saturation of arterial blood (SpO2), ECG in 12 standard leads, etc.), performed an echocardiography in the B-mode with the definition of linear and volume indicators of the left ventricle, as well as the global (by the ejection fraction (EF) and local contractile activity of the myocardium by the Simpson method. The functional state of the vascular endothelium was determined by the concentration of endothelin-1 (ET-1) in the blood plasma and the content of stable NO metabolites [5]. The determination of endothelin-1 (ET-1) in serum was carried out using for determining the ultimate stable metabolites of NO in the blood. Results. It has been established that patients with ACS (MI) after percutaneous coronary intervention often develop reperfusion syndrome with manifestations of left ventricular insufficiency and rhythm disturbances. Substantial clinical and functional improvement was noted under the influence of standard medical treatment in patients of control group. At the same time postinfarction remodeling with systolic and diastolic function of the heart, with the development of heart failure syndrome and endothelial dysfunction of blood vessels, and also remained resistant to extrasystole therapy, progressed.Patients in the experimental group under the influence of complex medical treatment with the inclusion of L-arginine and L-carnitine marked a significant decrease in the frequency of violations of rhythm and conduction for the second day of observation, as well as a decrease in the manifestations of post-infarction remodeling of LV, which ultimately manifested a significant improvement in myocardial contractility (EF increased by 13%) and decreased diastolic dysfunction. Improvement of the inotropic function of the heart and a significant reduction in the frequency and severity of reperfusion arrhythmias was achieved precisely due to cardiometabolic effects of L-carnitine. In addition, in patients undergoing additional treatment with L-arginine and L-carnitine after 10 days of treatment, the activity of ET-1 was significantly lowered and the concentration of nitrogen oxide metabolites in the blood plasma increased and reach the level of healthy subjects (P> 0,05). So, they recovered the endothelial function of the vessels.Conclusions: In the first day after percutaneous coronary intervention on the background of standard drug therapy was most often diagnosed with reperfusion syndrome with manifestations of acute left ventricular failure and arrhythmias and conduction.The use of complex drug therapy with the inclusion of L-arginine and L-carnitine on the background of an individualized cardiorehabilitation program led to a significant improvement in the parameters of central cardiohemodynamics and restoration of vascular endothelial function, was accompanied by a significant decrease in the frequency of development and severity of such complications of ACS (MI) as reperfusion arrhythmias and acute left ventricular failure.