[Recommendations on telestroke in Europe]. / Evropeiskie rekomendatsii po telemeditsine insul'ta.

INTRODUCTION: This paper is an adapted translation of recommendations on telestroke provided by the European Stroke Organization. Lack of stroke specialists determines that many European rural areas remain underserved. Use of telemedicine in stroke care has shown to be safe, increase use of evidence-based therapy and enable coverage of large areas of low population density. An aim of the study is to summarise the following recommendations of the Telestroke Committee of the European Stroke Organization on the setup of telestroke networks in Europe: Hospitals participating in telestroke networks should be chosen according to criteria that include population density, transportation distance, geographic specifics and in-hospital infrastructure and professional resources. Three hospital categories are identified to be part of a hub-and-spoke network: (1) the Telemedicine Stroke Centre (an European Stroke Organization stroke centre or equivalent with specific infrastructure and setup for network and telemedicine support), (2) the telemedicine-assisted stroke Unit (equivalent to an European Stroke Organization stroke unit but without 24 h onsite stroke expertise) and (3) the telemedicine-assisted stroke ready hospital (only covering hyperacute treatment in the emergency department and transferring all patients for further treatment).

Mechanical revascularization for acute ischemic stroke: a single-center, retrospective analysis.

BACKGROUND: Endovascular mechanical revascularization (thrombectomy) is an increasingly used method for intracranial large vessel recanalization in acute stroke. The purpose of the study was to analyze the recanalization rate, clinical outcome, and complication rate in our stroke patients treated with mechanical revascularization. METHODS: A total of 57 patients with large vessel stroke (within 3 h for anterior and 12 h for posterior circulation) were treated with mechanical revascularization at a single center during 24 months. The primary goal of endovascular treatment using different mechanical devices was recanalization of the occluded vessel. Recanalization rate (reported as thrombolysis in cerebral infarction [TICI] score), clinical outcome (reported as National Institutes of Health Stroke Scale [NIHSS] score and modified Rankin scale [mRS] score), as well as periprocedural complications were analyzed. RESULTS: The mean age of the patients was 63.1 ± 12.9 years, with baseline median NIHSS score of 14 (interquartile range, 9.5-19). Successful recanalization (TICI 2b or 3) was achieved in 41 (72 %) patients. Twenty patients (35 %) presented with favorable outcome (mRS ≤2) 30 days after stroke. Overall, significant neurological improvement (≥4 NIHSS point reduction) occurred in 36 (63 %) patients. A clinically significant procedure-related adverse events (vessel disruption, peri/postprocedural intracranial bleeding) defined with decline in NIHSS of ≥4 or death occurred in three (5 %) patients. CONCLUSIONS: The study showed a high recanalization rate with improved clinical outcome and a low rate of periprocedural complications in our stroke patients treated with mechanical revascularization. Therefore, we could conclude that endovascular revascularization (primary or in combination with a bridging thrombolysis) was an effective and safe procedure for intracranial large vessel recanalization in acute stroke.

Cerebrovascular reactivity to l-arginine in the anterior and posterior cerebral circulation in migraine patients.

OBJECTIVE - Cerebral infarction preferentially affects the posterior cerebral artery distribution in migraine patients. The results obtained from the few known studies that have compared the anterior and posterior cerebral endothelial function are contradictory. To the best of our knowledge, cerebrovascular reactivity to L-arginine (CVR), measured by transcranial Doppler sonography (TCD), has not been previously used to determine the posterior cerebral endothelial function in migraine patients with (MwA) and without aura (MwoA). MATERIALS AND METHODS - Forty migraine patients without comorbidities (20 MwA, 20 MwoA) and 20 healthy subjects were included. By employing strict inclusion criteria, we avoided the possible vascular risk factors. Mean arterial velocity in the middle cerebral artery (MCA) and the posterior cerebral artery (PCA) was measured by TCD before and after infusion of L-arginine, and CVR to L-arginine was then calculated. RESULTS - All migraine patients had lower CVR to L-arginine in PCA (P = 0.002) and similar in MCA (P = 0.29) compared to healthy subjects. This difference was also present in MwA and MwoA compared to healthy subjects (P = 0.003). CONCLUSIONS - Lower CVR to L-arginine in PCA in migraine patients could associate migraine and cerebral infarcts that are more common in the posterior cerebral artery distribution.

Effect of generalized sympathetic activation by cold pressor test on cerebral hemodynamics in diabetics with autonomic dysfunction.

BACKGROUND: We examined the effects of the cold pressor test on the cerebral circulation in diabetics with autonomic dysfunction without orthostatic hypotension using transcranial Doppler. METHODS: Twenty diabetics with autonomic dysfunction and 19 age-matched healthy controls participated in the study. The mean arterial blood velocity was measured in the middle cerebral artery during the cold pressor test together with the mean arterial blood pressure. RESULTS: The mean arterial blood velocity significantly (p < 0.01) increased during the 1st, 2nd, and 3rd min of the cold pressor test by 10.6, 14.1, and 13.4%, respectively, in the control subjects and by 5.8, 7.2, and 6.8%, respectively, in the diabetics. Simultaneously, the mean arterial blood pressure significantly (p < 0.01) increased by 12, 26, and 23%, respectively, in the controls and by 9.4, 12.4 and 12.9%, respectively, in the diabetics. The increases in the mean arterial velocity as well as in the mean arterial blood pressure were significantly higher in the controls than in the diabetics (p < 0.01). The change in the mean arterial blood pressure related significantly to the change in the mean arterial blood velocity both in the controls (p < 0.01, r = 0.76) and in the diabetics (p < 0.01; r = 0.59). The slope of the regression line was significantly steeper in the controls (b = 0.42, SE = 0.05) as compared with the diabetics with autonomic dysfunction (b = 0.27, SE = 0.05; p = 0.02). Moreover, also the relative increase in the cerebrovascular resistance index was higher in the controls than in the diabetics (p < 0.05). CONCLUSION: These findings in the diabetics with autonomic neuropathy, but without orthostatic hypotension, suggest a failure in the cerebral autoregulation due to impaired cerebrovascular neurogenic control.

Testing of cerebral endothelium function with L-arginine after stroke.

BACKGROUND: Endothelium-dependent vasodilatation could be impaired during hypoperfusion. L-arginine (L-A), a precursor of nitric oxide, is able to elicit endothelium-dependent vasodilatation. To determine cerebral vascular endothelial function in the early stages after ischemic stroke, we studied cerebrovascular reactivity to L-A with transcranial Doppler (TCD). METHODS: The study group consisted of 15 patients with the middle cerebral artery syndrome, aged 57.6+/-9.8 years. They were investigated on days 7 to 10 after ischemic stroke. The control group consisted of 15 healthy volunteers, aged 58+/-10.7 years. All subjects received an intravenous infusion of L-A over 20 min at a rate of 1.5 g/min. The mean arterial velocity (vm) was measured in both middle cerebral arteries by using a bitemporal monitoring system (Multi-Dop X4, DWL). At the same time, the mean arterial pressure (MAP) and heart rate (HR) were measured by Finapres and ECG. The end-tidal CO2 (Et-Co2) was monitored by capnograph. The Vm over 5-min intervals at rest and during the infusion of L-A was determined by using the DWL TCD8 software. RESULTS: The Vm significantly increased in both hemispheres of both groups (p=0.00). Vm differences between rest and L-A stimulation were lower in the ischemic hemispheres compared to the healthy ones (p=0.00), but did not differ between the ischemic hemispheres and hemispheres of the healthy group (p>0.05). MAP, HR and Et-Co2 did not change during the infusion (p>0.05). CONCLUSIONS: Cerebrovascular reactivity to L-A is impaired in patients with recent stroke. The amino acid could thus be useful in testing endothelium function both in healthy persons and in stroke patients since endothelium dysfunction seems to be an important factor in reperfusion injury.

The effect of age on cerebrovascular reactivity to cold pressor test and head-up tilt.

OBJECTIVE: To compare the cold pressor test (CPT) and head-up tilt (HUT) responses of the older and younger healthy individuals by transcranial Doppler. SUBJECTS AND METHODS: Forty healthy volunteers were divided into two age groups (18-39 years, 40-69 years). Mean blood velocity (v(m)) in both middle cerebral arteries was monitored during CPT and HUT. Mean arterial blood pressure, heart rate and end-tidal CO(2) (Et-CO(2)) were measured simultaneously. RESULTS: The v(m) increased by 7.1% during CPT and decreased by 10.1% during HUT. The v(m) responses were significantly lower in the older group (P < 0.01). Linear regression analysis showed a significant effect of age on dv(m) during both CPT (P < 0.01) as well as HUT (P < 0.01). CONCLUSION: The age affected the v(m) responses to CPT and HUT in the group of older subjects.

Influence of the cold pressor test on the middle cerebral artery circulation.

Cold pressor test (CPT) evokes generalized activation of the sympathetic nervous system (SNS). The activity of SNS may be estimated by monitoring the mean blood velocity (v(m)) in the middle cerebral artery (MCA) by using a transcranial Doppler monitoring system (TCD). To determine the response of SNS, we studied the v(m) during CPT. Thirty-four healthy volunteers, 13 female and 21 male (mean age 34 +/- 9.5 years, range 18 to 55 years) participated in our study. The experiment consisted of a 5-min baseline period followed by a 3-min immersion of the right hand in ice water. Blood velocity in both MCA's was monitored by bitemporal 2 MHz probes by using a Multi-Dop X4. MAP and heart rate (HR) were measured simultaneously by a Finapres non-invasive blood pressure monitor and a computerized ECG system. End-tidal CO2 (Et-CO2) was measured with an infrared capnograph. To determine v(m) over a chosen time interval the TCD-8 software was utilized. The results showed that during CPT v(m), MAP, and HR increased significantly (P < 0.01) for 9.8%, 18.5%, and 3.6%, respectively. Et-CO2 did not change significantly (P > 0.05). The increase of v(m) was also significantly higher in the stimulated hemispheres (P = 0.005) regarding to unstimulated ones. The increase of v(m) during CPT was not gender dependent. To establish the association between variables the models of multivariate regression were used. Multiple regression CPT model was significant (P < 0.01) and fitted data moderately well (R2 = 0.28). MAP and Et-CO2 were significant in the model (P < 0.01). It seems that the reactivity of the SNS can be estimated by measuring v(m) with TCD during CPT.

Transient ischemic attacks, risk factors, and precerebral color doppler angiosonography.

The aim of this study was to ascertain the importance of color-coded Doppler sonography (CCDS), a noninvasive examination technique, in early detection of atherosclerotic lesions in precerebral arteries. CCDS was utilized in a group of patients with one or several transient ischemic attacks (TIA) and in a group of non-TIA (NTIA) cases, so that the degree of atherosclerotic lesions of precerebral vessies in TIA and NTIA patients might be compared. The presence of risk factors for cerebrovascular disease (CVD) was compared in both groups as well. We examined 87 patients with TIA (38 women and 49 men), aged 19-86 years (mean, 60.97 ± 11.97 years) and 48 NTIA patients (22 women and 26 men), aged 35-85 years (mean,60.04 ± 9.37years). No statistically significant differences in age and gender were found between the groups. A significant difference was found between the common carotid artery intimal-medial thickness (CCA IMT) in TIA patients (CCA IMT right + left = 1.12 ± 0.44 mm) and NTIA patients (CCA IMT right + left = 0.91 ± 0.32 mm) (p < 0.0001). A positive significant association was found between both groups in the number of different plaques (p < 0.0001) and the number of stenoses (p < 0.0001). When risk factors were compared, the difference between TIA and NTIA groups was statistically significant in regard to high-density lipoproteins (p < 0.002), total cholesterol (p < 0.004), and blood glucose concentrations (p < 0.013), as well as systolic blood pressure (p < 0.011). In conclusion, Doppler sonographic changes in precerebral arteries were present in the TIA group in spite of the fact that both groups had identical risk factors for CVD. CCDS is a valuable aid for early detection of TIA patients who have a significant risk of developing brain infarction.