[Predictors of acute cerebral embolic lesions during carotid artery stenting]. / Prediktory ostrykh tserebral'nykh émbolicheskikh povrezhdenii pri stentirovanii sonnoi arterii.

The authors carried out a prospective study aimed at revealing predictors of acute embolic lesions of cerebral vessels during angioplasty with stenting of the internal carotid artery. The study enrolled a total of 54 patients who between May 2015 and December 2018 underwent carotid angioplasty with stenting performed at the Department of Vascular and Endovascular Surgery of the Research Centre of Neurology. The procedure of internal carotid artery stenting may be accompanied by intraoperative acute embolic lesions. In order to reveal intraoperative acute embolic lesions of cerebral vessels all patients before and 24 hours after the intervention were subjected to diffusion-weighted magnetic resonance imaging. Thirty-six patients received classical carotid stents (Xact and Acculink) and 18 patients received Casper stents. The patients of both groups were comparable by 24 characteristics studied, including the incidence of intraoperative acute cerebral embolic lesions (18/36 for the classical stents and 10/18 for the Casper stent), which made it possible to unite them into one group in order to increase the power of the study. All acute embolic lesions detected by the diffusion-weighted magnetic resonance imaging (prior to stenting and 24 hours thereafter) were clinically, asymptomatic with no perioperative stroke observed. In order to reveal predictors of intraoperative acute embolic lesions of cerebral vessels we analysed 22 characteristics of the patients, with the obtained findings demonstrating the following signs: a low-intensity (below 20 dB) ultrasonographic signal reflected from fragments of an atherosclerotic plaque during ultrasound examination prior to stenting (p=0.001) - a sign strongly associated with acute embolic lesions (sensitivity - 75%, specificity - 92%); symptomatic stenosis according to the anamnestic data (p=0.02) - a sign significantly associated with acute embolic lesions; female gender (p=0.06) - a sign moderately associated with acute embolic lesions; a history previously endured (according to the anamnestic data) operations on coronary and/or carotid arteries (p=0.09) - a sign weakly associated with acute embolic lesions. Based on the obtained findings we proposed a prognostic scale to assess the risk of acute embolic lesions of cerebral vessels during internal carotid artery stenting. Knowing the factors associated with intraoperative acute embolic lesions will allow the endovascular surgeon to single out the patients at increased risk of acute embolic lesions.

[Brainstem auditory evoked potentials in neurophysiological assessment of brain stem dysfunction in patients with atherostenosis of vertebral arteries]. / Akusticheskie stvolovye vyzvannye potentsialy v neirofiziologicheskoi otsenke disfunktsii stvola mozga u patsientov s aterostenozom pozvonochnykh arterii.

AIM: To assess brain stem dysfunction in patients with hemodynamically significant stenosis of vertebral arteries (VA) using short latency brainstem auditory evoked potentials (BAEP). MATERIAL AND METHODS: The study group included 50 patients (mean age 64±6 years) with hemodynamically significant extracranial VA stenosis. RESULTS: Patients with hemodynamically significant extracranial VA stenosis had BAEP abnormalities including the elongation of interpeak intervals I-V and peak V latency as well as the reduction of peak I amplitude. After transluminal balloon angioplasty with stenting of VA stenoses, there was a shortening of peak V latency compared to the preoperative period that reflected the improvement of brain stem conductive functions. CONCLUSION: Atherostenosis of vertebral arteries is characterized by the signs of brain stem dysfunction, predominantly in the pontomesencephal brain stem. After transluminal balloon angioplasty with stenting of VA, the improvement of brain stem conductive functions was observed.

[Intraoperative monitoring of cerebral blood-flow and condition of cerebral at open and endovascular interventions in carotid system].

The aim of our research is to study hemodynamic and embolic situation during the carotid endarterectomy (CEA), carotid angioplastic and stenting (CAS), and to reveal the prognostic significance of the data provided by intraoperative monitoring of the brain blood flow in exposing acute ischemic lesions in brain. Intraoperative monitoring of blood flow in artery ophthalmic vas carried out with 60% of patients, in the middle cerebral artery-with 40% during the main stages of CEA, and with 64 patients in the middle cerebral artery during CAS. The comparison of the data of intraoperative monitoring of blood flow in middle cerebral artery with the result of brain diffusion-weighted magnetic resonance imaging (DW-MRI) 24 hours after the operation shows, that solid microembolic signals and vasospasm are prognostic signals (sensibility and specifics make up 95%) in the development of acute ischemic cerebral lesions. The monitoring of blood flow in artery ophthalmic is of the greatest diagnostic value in estimation of the hemodynamic situation, but it is of the lowest practical value in detecting microembolic signals. According to the data of the intraoperative blood flow monitoring in middle cerebral artery in group CEA the development of acute ischemic cerebral lesions were predicted with 11,1% of patients and the cause of postoperative stroke, developed by 2,9% of the patients, was specified. According to the result of DW-MRI, acute ischemic cerebral lesions were diagnosed with 21% of patients, that is, 18% of ischemic cerebral lesions were asymptomatic. In group CAS ischemic cerebral lesions were prognosed with 30% of patients, actually they were later detected with 40,6% of cases by means of DW-MRI. According to the data of intraoperative of blood flow monitoring the cause of the development of postoperative stroke was specified in 6,2% of cause; in 34,4% of cause the acute ischemic cerebral lesions were asymptomatic.

[Ultrastructural changes of skin arteries in patients with spontaneous cerebral artery dissection].

Spontaneous cerebral artery dissection is a common cause of ischemic stroke in young adults and children. Dissection is often related to arterial wall weakness the cause of which is unknown. An aim of the present paper was to carry out an electron microscopic study of skin arteries and arterioles in patients with ischemic stroke caused by cerebral artery dissection. Skin biopsy samples from 3 patients (2 men and one women, 15, 25 and 43 years of age, respectively) were studied. Electron microscopy revealed changes of endothelial, smooth muscle cells and fibroblasts in the skin microvessels. These changes included the decrease in the number of mitochondria and their alterations (vacuolization, destruction of the cristae, the presence of the needle-shaped crystals and crystal-like inclusions) and swelling of the endoplasmic reticulum. Some of these changes were characteristic of mitochondrial diseases. The changes in the extracellular matrix (thickening of the subendothelial layer and deposition of microcalcificats) were also detected. It is assumed that the mitochondrial cytopathy found in the skin microvessels may be also present in large cerebral arteries. This could underlie dysplastic changes in the cerebral artery wall and predispose to its dissection.

[Results of proximal vertebral arteries endovascular interventions].

OBJECTIVE: To evaluate immediate and long-term clinical and ultrasound efficacy of proximal vertebral arteries stenting. We studied 74 subjects (age 61+/-10 years) who underwent transluminal balloon angioplasty with stenting of vertebral arteries (77 vessels). Technical success (i.e., residual stenosis < 20%) was achieved in 95% patients. No events (acute stroke, myocardial infarction, or death) were recorded during the procedure or in early postoperative period. Clinical improvement was seen in 81% patients presented with symptoms of vetebrobasilar insufficiency at the baseline (n = 52). Sixty six patients (89%) were followed up in the late postoperative period (6 to 54 months after the intervention). No events of acute stroke were recorded in the vertebrobasilar circulation. Relapse of vertebrobasilar symptoms after temporary improvement was seen in 13% patients. Stent restenosis/occlusion was diagnosed in 36% patients although no relationship was revealed between the alteration of stent patency and relapse of clinical symptoms. Restenosis correlated with initial stenosis of > or = 70% (p < 0.05) and type of stent material. Use of cobalt chromium stents was associated with 2-fold decrease of restenosis rate vs non cobalt chromium stents (24% vs 50%, respectively, p < 0.05). Therefore, stenting of proximal vertebral arteries yields good technical and clinical results. High restenosis rate is a major problem of endovascular treatment of atherosclerosis and needs further evaluation.