Венозный отток по внутренним яремным венам при различной степени стеноза внутренних сонных артерий по данным ультразвукового исследования

Introduction. Type 2 diabetes is the most common form of endocrine disease. Diabetes is a well-established risk factor for stroke. Carotid endarterectomy (CEE) is the main method of preventing a serious complication of stroke in patients with carotid stenosis. Consequently, the assess of type 2 diabetes on the results of CEE is an urgent problem of angiosurgery.Aim: To assess effect of type 2 diabetes on cerebrovascular reserve capacity and brain structure in patients with carotid atherosclerosis by ultrasound and magnetic resonance diagnostic.Material and Methods. 44 patients with hemodynamically significant stenosis of the internal carotid arteries (ICA), who underwent ultrasound and magnetic resonance examinations of the carotid arteries at the pre- and postoperative stages were included in this study. Two groups were formed: group I (n =15) – with a verified diagnosis of type 2 diabetes, group II (n = 29) – without diabetes. To assess the cerebrovascular reserve, functional hypercapnic and hyperoxic tests were performed.Results. The analysis of the results showed statistically significant differences in the ICA blood flow in both groups. Intergroup comparison before surgery in the middle cerebral artery on the side of hemodynamically significant stenosis revealed a statistically significant difference in pulsation and peripheral resistance index. In the common carotid arteries on both sides, significant intergroup differences were found in the velocity parameters of blood flow after the CEE operation. The reactivity index in patients with surgical stenosis with type 2 diabetes in the hyperoxic test was statistically significantly different on the side of the stenosis compared to the same indicator in the group without diabetes. There were no statistically significant differences in the hypercapnic test. The value of reactivity index indicates a negative or paradoxical reaction.Conclusion. The use of simple and accessible functional tests to assess cerebrovascular reserve, plaque structure and changes in the brain in patients with type 2 diabetes at the stage of preoperative preparation according to ultrasound and MRI studies allows us to correct the treatment and subsequent protection of the brain at the stage of surgery to prevent possible complications.

Intermittent hypoxia-hyperoxia (IHH) is considered a method for inducing an organ-protective phenotype and acute stress response. The effect of short IHH on cerebral blood flow remains poorly studied. Objective. To examine the short-term impact of intermittent hypoxia-hyperoxia on cerebral hemodynamic parameters using ultrasound data. Materials and methods. The study included 20 volunteers aged 60—74 years. Individuals in the study group (n=10) underwent IHH sessions, while those in the control group (n=10) received a placebo. Ultrasound examination of the cerebral vessels was performed before the first procedure and 24 hours after the last. Hemodynamic assessment was done at rest, during a hypercapnic test and after IHH using B-mode, color and pulsed wave Doppler mapping. All participants underwent magnetic resonance imaging and magnetic resonance angiography. Results. In the study group, two subgroups were identified: with a positive reaction (n=7; increase in the reactivity index (RI) to 1.3—1.4) and a paradoxical reaction (n=3; decrease in RI to 0.8—0.9). All participants experienced reductions in systolic and diastolic blood pressure and heart rate; venous and central venous pressure remained unchanged. In a positive reaction, a statistically significant increase in the venous outflow velocity was observed, while in a paradoxical reaction, a decrease was noted. Arterial inflow parameters did not change significantly, and RI remained positive. No changes in the studied indicators were detected in the control group. Conclusion. Intermittent hypoxia-hyperoxia improves venous outflow in the majority of elderly patients without severe somatic pathology. Short-term assessment of the impact of this method on cerebral hemodynamics may be important for monitoring during intermittent hypoxia-hyperoxia sessions.

Aim. To study changes of geometric and hemodynamic characteristics of internal jugular veins (IJVs) using ultrasound in patients with atrial fibrillation (AF). Today, we have quite a lot of data on changes in cerebral arteries. There is much less information about venous changes using such a simple and accessible method as ultrasound, and data on cerebral venous outflow in AF are insufficient.Material and methods. This observational study included patients with permanent AF and patients with sinus rhythm and no history of arrhythmias. The AF group included 29 patients with AF, while the control group — 41 patients without arrhythmias. All patients underwent ultrasound of the following vessels: extracranial — IJV and common carotid artery (CCA), intracranial — basal vein of Rosenthal and middle cerebral artery. Arterial pressure and venous pressure (VP) in the bra­chial vein were measured.Results. According to the clinical characteristics of VP and central VP, patients in the AF group and the control group did not differ significantly. The area of the IJV was larger in the AF group as follows: on the right — 2,1±0,66 and 1,32±0,35 cm² in the AF group and in the control group with sinus rhythm, respectively (p=0,001); on the left — 1,59±0,55 and 1,22±0,43 cm² in the group with AF and in the control group, respectively (p=0,01). Moreover, time-averaged maximum (TAMAX) and mean (TAMEAN) velocities of IJVs in the AF group were significantly lower than in patients with sinus rhythm (on the right, TAMAX was 7,86±2,32 and 12,48±6,15 cm/sec in the AF group and in the control group, respectively (p=0,01); on the left — 7,40±2,35 and 11,37±5,24 cm/sec in the AF group and in the control group, respectively (p=0,01); on the right, TAMEAN was 4,82±1,65 and 7,70±3,22 cm/sec in the AF group and in the control group, respectively (p=0,01); on the left — 4,42±1,58 and 7,25±3,10 cm/sec in the AF group and in the control group, respectively (p>0,01). However, the velocity characteristics in the AF group remained within the lower reference limit. Similar velocity values by groups were obtained regarding basal veins of Rosenthal.Conclusion. Evaluation of the geometric and hemodynamic chara­cteristics of the IJV during a comprehensive ultrasound examination is necessary in patients with AF, since they are characterized by dilated IJV and decreased velocity parameters to lower reference limit. The ultrasound data of the IJV in patients with AF reflect the initial signs of venous outflow impairment. This can lead to an increase in peripheral resistance in the arterioles, and as a consequence, to impaired cerebral perfusion and cognitive dysfunction.