The main aim of the study was to investigate the effect of carotid endarterectomy on the prognosis of chronic cerebral ischemia in patients with symptomatic occlusions of the contralateral internal carotid artery, assess risks of surgical complications, and substantiate the staged surgical approach for treatment of patients with this pathology. The article analyzes the experience in surgical treatment of 83 patients with symptomatic ICA occlusions who underwent surgery for contralateral carotid artery stenosis. In 40 patients, only carotid endarterectomy (CEA) was performed on the side of hemodynamically significant stenosis (group 1). In 43 (52%) cases, apart from CEA, extracranial-intracranial (EC-IC) bypass was performed at the second stage (23 cases, group 2) or the first stage (19 cases, group 3). A surgical treatment approach was chosen based on clinical symptoms, severity of contralateral carotid artery stenosis, and the magnitude of perfusion deficiency in the territory of carotid occlusion. The conducted analysis revealed that patients with symptomatic occlusions and contralateral carotid artery stenoses represented a heterogeneous group with a different efficacy of carotid endarterectomy and with risks of perioperative complications. As cerebrovascular insufficiency in the territory of carotid occlusion and a related neurological deficit worsen, the risks of complications of contralateral carotid endarterectomy increase, and its clinical efficacy decreases. In these cases, cerebral revascularization on the ICA occlusion side should be performed at the first stage.