The article deals with the results of a comparative analysis of the state of the lower-limb lymphatic bed depending on the method of exposing the great saphenous vein (GSV) during the operation of coronary artery bypass grafting (CABA). Pronounced lesions of the lower-limb lymphatic system after surgical aggression provoke the development of complication such as lymphorrhea, lymphocele, and secondary oedema. The chosen objective method of assessment was radionuclide lymphoscintigraphy allowing of dynamically evaluating the alterations in the lymphatic system. We examined a total of 205 patients presenting with coronary artery disease and subjected to CABA. The patients were subdivided into two groups depending on the method used to expose the vein, including 109 patients with endoscopic exposure of the vein and group two consisting of 96 patients undergoing open exposure of the vein. Lymphoscintigraphy was performed in 18 patients with open exposure of the vein and in 23 patients with endoscopic exposure before and after the operation. Analysing the obtained findings revealed that according to the results of lymphoscintigraphy endoscopic exposure of the GSV was accompanied predominantly by an insignificant degree of impairment of the lymphatic drainage in 34.4%, whereas 94.4% were found to have mainly moderate-to-severe impairments. The lymphatic complications rate in the group with open exposure of the GSV was considerably higher which was mainly associated with the development of early oedema confirmed by an increased volume of the lower third of the crus of the operated limb. Radionuclide lymphoscintigraphy may be recommended as a method of early preclinical diagnosis of impairments of lower-limb lymphatic drainage in patients after exposure of the GSV in order to predict the development of clinically significant complications.