The article deals with intraoperative assessment of the blood flow in the coronary arteries and internal thoracic artery before and after myocardial revascularization. This is accompanied and followed by ultrasonographic characteristics of the coronary blood flow before and after surgical intervention, as well as competence of anastomoses and functional state of revascularization depending on the degree of the atherosclerotic lesion and the diameter of coronary arteries. The average linear and volumetric velocities of the blood flow in the coronary arteries were found to depend upon the degree of the lesion of coronary arteries, the diameter and capacity of the coronary bed. The work was based on studying a total of forty-eight patients presenting with coronary artery disease and subjected to myocardial revascularization using the internal thoracic artery (ITA). Also determined was efficacy of myocardial revascularization in different diameters of the coronary arteries and parameters of the ITA blood flow.