Features of Cerebral Hemodynamics and Cognitive Status in Patients with Chronic Ischemia of the Brain on the Background of Stenosing Atherosclerosis of the Brachiocephalic Arteries

Abstract

Aim. To study the state of cerebral circulation and cognitive status (CS) in patients with chronic cerebral ischemia (CCI) associated with atherosclerotic lesions of the brachiocephalic arteries (BCA).

Materials and Methods. A total of 128 individuals aged 42 to 60 years were examined, including patients with CCI in the compensated (Group I, n=24) and subcompensated (Group II, n=38) stages, as well as 46 patients (Group III) with decompensated CСI, who had a history of an ischemic stroke (IS). The state of the carotid (CA), and vertebral (VA) arteries was assessed, as well as the time-averaged maximum blood flow velocity (TAMX) in the cerebral arteries, as well as in the vertebral (VA, segment V4) and basilar (BA) arteries, the functioning of the anterior (AComA) and posterior (PComA) communicating arteries. The assessment of CS was performed using the Mini-Mental State Examination (MMSE), Frontal Assessment Battery (FAB), and a 10-word recall test.

Results. In Group I, isolated lesions of the CA or VA were observed, whereas in Groups II and III, multiple lesions predominated. The severity of CCI correlated with a decrease in TAMX, most pronounced in the middle cerebral artery (MCA) in Group II (p < 0.05) and Group III (p < 0.01). Such vascular ischemia was clinically accompanied by an increase in ataxic, pseudobulbar, dysmnestic, and pyramidal syndromes. In patients with a non-functioning AComA and hemodynamically significant BCA lesions, a decline in memory, intelligence, and behavioural stability was noted. In cases of non-functioning PComA, a decrease in TAMX in the posterior cerebral (PCA), basilar (BA), and vertebral (VA, V4) arteries was associated with more severe vestibular and ataxic symptoms. According to the MMSE, the average score indicated mild cognitive reduction (CR) in Group I (25.5 ± 0.6 points) and mild dementia in Groups II and III (23.6 ± 0.2 and 20.9 ± 0.4 points, respectively). In Group III, these values approached the threshold of moderate dementia. In the FAB test, moderate CR with impaired praxis and spatial activity was noted in Group I, severe CR with impaired praxis and object function in Group II, and dementia in Group III.

Conclusions. In patients with decompensated CCI, hemodynamically significant stenoses of the CA were often combined with VA lesions. The functional state of the AComA and PComA plays an important role in the development of clinical manifestations of CCI. Patients with compensated CCI exhibited moderate cognitive impairment, those with subcompensated CCI demonstrated severe cognitive impairment, while patients with decompensated CCI and a history of IS showed signs of vascular dementia.