| Abstract [eng] |
Atherosclerosis of extracranial arteries is a widely acknowledged risk factor of cerebral stroke; the changes narrowing these arteries cause 15 – 20% of all ischemic strokes. The carotid endarterectomy is method of treatment aimed to prevent recurrent ischemic events and severe stroke in presence of symptomatic significant stenosis of internal carotid artery. Although the benefits and efficacy of CAE are undoubted, the time since ischemic event till endarterectomy remains an object of discussions. Despite the carotid endarterectomy is recommended within 2 weeks of the symptomatic event, only a minority of patients undergoes surgery within the recommended time and this is related not only to logistic factors, but also to a traditional conviction, that operation after a symptomatic cerebrovascular event has higher incidence of complications. The majority of studies evaluating CAE outcomes are based on criteria of mortality, repeated strokes and duration of hospitalization. There are no data regarding changes of patient neurological status and factors, influencing neurological outcomes of symptomatic patients who were operated on because of significant stenosis of ICA. The indications for surgery of asymptomatic internal carotid artery after ischemic stroke of vertebrobasilar or contra-lateral arterial territory are based on small observational studies or presentations of postoperative results only. The impact of operative treatment of these patients on functional neurological state and outcomes is not evaluated. Objective of the thesis: to assess changes of neurological status of patients after brain ischemia before and after internal carotid artery endarterectomy and identify outcome-related factors. The study included 75 symptomatic patients and 26 patients with ischemia of another artery territory. Symptomatic patients are at high risk of recurrent ischemia before operation. After the first ischemic event 52% of patients suffer recurrent ischemia events before operation. The highest risk of recurrent ischemic event occurs within first two weeks. The patients with repeated ischemia differ from the patients with a stable course of the disease: during the first occurrence the stroke’s predictive scale (ABCD2) score are higher and this group contains a larger number of patients with critical stenosis and hypoechogenic atherosclerotic plaques (type 1 and 2), these patients are more likely to have collateral blood flow through the ophthalmic artery and anterior communicating artery as well as lower ipsilateral MCA pulsatility indices. The patients suffering from recurrent ischemic events have worse neurological status before surgery. This group of patients included a smaller number of patients with excellent outcome (mRS<2) 3 months and 1 year after operation. The comparison of the patients operated on at different time-points after ischemic event showed that the risk of surgery seemed to be similar and the differences of neurological outcomes depended on both initial and preoperative status of the patient. The patients with symptomatic TIA or stroke operated on within 2 weeks have good prognosis: 75.8% and 77.4% of the patients were disability-free (mRS<2) after 3 months and 1 year, respectively. Furthermore, 97.0% and 96.8% of the patients became functionally independent (mRS≤2) after 3 months and 1 year, respectively. The patients suffering from ischemia of another artery territory had different clinic factors resulting in statistically significant higher operative risk. This group included a smaller number of patients with excellent outcomes (mRS<2) after 3 months and 1 year compared with symptomatic patients. The outcomes after 3 months of symptomatic patients (mRS>2) are predicted by preoperative status (evaluated by mRS) and surgery complications, after 1 year – by the same factors as well as echogenicity of the plaque in operated symptomatic artery. The outcomes of all operated patients after 3 months are predicted by preoperative mRS and surgery complications and after 1 year – by the same factors and the patient’s age. |
