Relationship between serum endothelin-1 and in-stent restenosis following vertebral artery stenting.

The study objective was to investigate the relations between serum endothelin-1 and in-stent restenosis in vertebral artery stenting. Sixty-eight patients undergoing re-examination of vertebral artery stenting in the Department of Cerebrovascular Disease, Hangzhou Third People's Hospital, between April 2019 and October 2022, were invited to participate. According to the presence of vertebral artery stenting, patients were divided into the restenosis (n = 19) or non-restenosis (n = 49) groups. General clinical data and endothelin-1 levels were compared between the groups. Logistic regression analysis was used to explore the relations between endothelin-1 level and risk for in-stent restenosis. Receiver operating characteristic curves were drawn to test the diagnostic value of serum endothelin-1 level for in-stent restenosis. Compared with the non-restenosis group, restenosis group levels of low-density lipoprotein, triglycerides, and endothelin-1 were significantly higher (p < 0.05) Multivariate logistic regression analysis showed that endothelin-1, stent length, and low-density lipoprotein were independently associated with in-stent restenosis (odds ratio = 1.502, 95% confidence interval: 0.042 ~ 0.212, p = 0.000; odds ratio = 1.899, 95% confidence interval: 1.116 ~ 2.237, p = 0.000; odds ratio = 1.899, 95% confidence interval: 1.228 ~ 3.337, p = 0.001, respectively). Area under the curve for serum endothelin-1 in the diagnosis of vertebral artery in-stent restenosis was 0.938. The best diagnostic cut-off value was 11.94 ng/L. Sensitivity was 89.5%. Specificity was 85.7%. These cumulative data indicate that endothelin-1 level is independently associated with in-stent restenosis.

Plasma Homocysteine and Prognosis of Patients with Recanalization after Acute Basilar Artery Occlusion: An Analysis from the Acute Basilar Artery Occlusion Study (BASILAR) Nationwide Prospective Registry.

BACKGROUND: Few studies have investigated the association between plasma Homocysteine (Hcy) levels in patients with recanalization after acute Basilar Artery Occlusion (BAO). OBJECTIVE: This study investigated the predictive value of Hcy on the clinical prognosis of patients with recanalization after acute BAO. METHODS: Altogether, 829 participants were recruited from the standard medical treatment plus endovascular treatment group of the Acute Basilar Artery Occlusion Study (BASILAR). Hcy levels were measured the morning after admission. The primary outcome was a combination of death and major disability (modified Rankin Scale score 4-6) at 90 days, and the secondary outcome was the mortality of patients with recanalization after acute BAO within 90 days. We used multivariable logistic regression modeling to estimate the association between Hcy and prognosis in our participants at 90 days. RESULTS: Altogether, 647 patients were assessed, and 302 patients were included in this study. The median was 12.88 µmol/L, and the mean Hcy concentration was 15.49 µmol/L. Elevated plasma Hcy levels (Hcy >12.88 µmol/L) were associated with poor functional outcomes (adjusted odds ratio 1.922, 95% confidence interval (CI) 1.048-3.528, P=0.035), but not with mortality (adjusted odds ratio 1.605, 95% CI 0.986-2.489, P=0.058). In further subgroup analysis, the conclusion was consistent in all predefined subgroups. CONCLUSION: Our analysis suggests that elevated plasma Hcy levels have a predictive value for functional outcomes in patients with recanalization after acute BAO during the 90-day follow-up period, but not for mortality.

[SERUM CONTENTS OF SUBSTANCE P, ENDOTHELIN-1 AND VASOACTIVE INTESTINAL PEPTIDE IN CHILDREN WITH RECURRENT BRONCHITIS AND VERTEBROBASILAR INSUFFICIENCY].

The recurrent bronchitis (RB) course is caused by the bronchi secretory-evacuation mechanisms state, which provide clearance from pathogens. This mechanism can be disrupted by vegetative reflexes and neuropeptides imbalance that develops in children with the syndrome of the vertebrobasilar arterial system (SVBAS). The objective: study of the neurogenic maintenance of the RB pathogenesis in children with SVBAS by studying the serum content of substances affecting of the bronchial mucosa secretory-evacuation function and inflammatory activity (substance P, vasoactive intestinal peptide - VIP and endothelin-1 - ET-1). 90 children aged 7 to 11 years were examined, 3 observation groups were formed: Group 1 - children with RB and SVBAS (n=30); Group 2 - children with SVBAS without RB (n=30); Group 3 - children with RB without SVBAS (n=30). In the Group 1, compared with the 2nd and 3rd, there was an increase in the children number with high serum content of substance P (by 66.7% and 50.0%, respectively, p<0.05) and ET -1 (by 23.3% and 40.0%, respectively, p<0.05), low content of VIP (by 46.7% and 23.4%, respectively, p<0.05). Children with RB and SVBAS have serum level imbalance of the pro-inflammatory substance P, ET-1 and anti-inflammatory VIP as the bronchitis severe course basis.

Total and differential leukocyte counts in ischemic stroke caused by vertebrobasilar artery dissection.

INTRODUCTION: Vertebrobasilar artery dissection(VBD) is a common etiology of posterior circulation stroke(PCS). However, the etiology of VBD itself remains unclear. The present study aimed to test whether inflammation is involved in the mechanism of VBD by evaluating its relationship with total and differential leukocyte counts. METHODS: Patients with PCS caused by VBD or by large artery atherosclerosis(LAA) were recruited between January 1, 2012 and December 31, 2014 from the Taipei Veterans General Hospital. Age- and sex-matched non-stroke(NS) volunteers were also included. Univariate and multivariate analyses were performed to compare total/differential leukocyte counts among VBD, LAA, and NS groups. RESULTS: One-hundred-one patients with VBD [average age: 64.8(15.1) years; 77(76.2%) males], 70 with LAA [average age: 73.9(10.6) years; 44(62.9%) males], and 202 NS [average age: 64.8(15.1) years; 77(76.2%) males] patients were included in the present study. Compared with the NS and LAA groups, respectively, the VBD group had significantly higher total leukocyte and neutrophil counts and frequency of high leukocyte (>10,000 × 106/L) and high neutrophil (>8000 × 106/L) counts. Multivariate analyses, adjusted for age, sex, and vascular risk factors, showed that the VBD group, compared with the other groups, had an odds-ratio of 5.04 (95% confidence interval:2.43-10.43) and 5.90 (2.70-12.92) with respect to the prevalence of high leukocyte and high neutrophil counts. CONCLUSION: VBD was associated with high leukocyte and neutrophil counts. Our results support that inflammation and neutrophil-related pathophysiology might be involved in the mechanism of VBD; however, the causal relationship would need further investigations.

Cardiac Biomarkers Predict Large Vessel Occlusion in Patients with Ischemic Stroke.

BACKGROUND AND PURPOSE: Cardiac biomarkers may help identify stroke mechanisms and may aid in improving stroke prevention strategies. There is limited data on the association between these biomarkers and acute ischemic stroke (AIS) caused by large vessel occlusion (LVO). We hypothesized that cardiac biomarkers (cardiac troponin and left atrial diameter [LAD]) would be associated with the presence of LVO. METHODS: Data were abstracted from a single center prospective AIS database over 18 months and included all patients with AIS with CT angiography of the head and neck. The presence of LVO was defined as proximal LVO of the internal carotid artery terminus, middle cerebral artery (M1 or proximal M2), or basilar artery. Univariate analyses and predefined multivariable models were performed to determine the association between cardiac biomarkers (positive troponin [troponin ≥0.1 ng/mL] and LAD on transthoracic echocardiogram) and LVO adjusting for demographic factors (age and sex), risk factors (hypertension, diabetes, hyperlipidemia, history of stroke, congestive heart failure, coronary heart disease, and smoking), and atrial fibrillation (AF). RESULTS: We identified 1234 patients admitted with AIS; 886 patients (71.8%) had vascular imaging to detect LVO. Of those with imaging available, 374 patients (42.2%) had LVO and 207 patients (23.4%) underwent thrombectomy. There was an association between positive troponin and LVO after adjusting for age, sex and other risk factors (adjusted OR 1.69 [1.08-2.63], P = .022) and this association persisted after including AF in the model (adjusted OR 1.60 [1.02-2.53], P = 0.043). There was an association between LAD and LVO after adjusting for age, sex, and risk factors (adjusted OR per mm 1.03 [1.01-1.05], P = 0.013) but this association was not present when AF was added to the model (adjusted OR 1.01 [0.99-1.04], P = .346). Sensitivity analyses using thrombectomy as an outcome yielded similar findings. CONCLUSIONS: Cardiac biomarkers, particularly serum troponin levels, are associated with acute LVO in patients with ischemic stroke. Prospective studies are ongoing to confirm this association and to test whether anticoagulation reduces the risk of recurrent embolism in this patient population.

Clinical research of persimmon leaf extract and ginkgo biloba extract in the treatment of vertebrobasilar insufficiency.

This paper aims to compare the curative effects of persimmon leaf extract and ginkgo biloba extract in the treatment of headache and dizziness caused by vertebrobasilar insufficiency. Sixty patients were observed, who underwent therapy with persimmon leaf extract and ginkgo biloba extract based on the treatment of nimodipine and aspirin. After 30 days, 30 patients treated with persimmon leaf extract and 30 patients with ginkgo biloba extract were examined for changes in hemodynamic indexes and symptoms, such as headache and dizziness. The results showed statistically significant differences of 88.3% for the persimmon leaf extract and 73.1% for the ginkgo biloba extract, P < 0.05. Compared to the group of ginkgo biloba extract, the group of persimmon leaf extract had more apparent improvement in the whole blood viscosity, plasma viscosity, fibrinogen, hematokrit, and platelet adhesion rate, and the difference was statistically significant (P < 0.05 or P < 0.01). Based on these analyses, it can be concluded that persimmon leaf extract is better than ginkgo biloba extract in many aspects, such as cerebral circulation improvement, cerebral vascular expansion, hypercoagulable state lowering and vertebrobasilar insufficiency-induced headache and dizziness relief.

Efficacy and safety of intensive statin therapy in Chinese patients with atherosclerotic intracranial arterial stenosis: a single-center, randomized, single-blind, parallel-group study with one-year follow-up.

OBJECTIVES: The purpose of this study is to validate the efficacy of intensive statin therapy for patients with atherosclerotic intracranial arterial stenosis (AICAS). METHODS: In this study, we performed a single-center, randomized, single-blind, parallel-group clinical trial. A total of 120 Chinese patients with AICAS were enrolled and randomly divided into three groups [low-dose atorvastatin therapy (LAT, 10mg/day), standard-dose atorvastatin therapy (SAT, 20mg/day), and intensive-dose atorvastatin therapy (IAT, 40mg/day) groups] in a 1:1:1 ratio. Evaluation variables, including changes in serum lipid profiles, degree of stenosis, and perfusion-related parameters derived from computed tomography perfusion (CTP) imaging from baseline to weeks 26 and 52, as well as the occurrence of cerebrovascular events during the study period, were used to compare the benefits of these three statin therapies. RESULTS: After 52 weeks of treatment, improvement of serum lipid profiles, degree of stenosis, and perfusion-related parameters were all significantly better in the IAT group. In addition, the cumulative probability of cerebrovascular events at 52 weeks was significantly lower in the IAT group than in the LAT group, although there was no statistical difference between the IAT group and the SAT group. The proportion of patients experiencing any adverse event was similar among the three treatment groups. Adverse events caused by IAT were generally mild; no serious adverse events occurred throughout the entire period of study. CONCLUSION: In conclusion, long-term use of IAT appears to be a safe and effective treatment at least for Chinese patients with AICAS.

Vasculitis revealed by posterior stroke.

Posterior ischaemic stroke is relatively uncommon, and its occurrence should alert clinicians to possible uncommon underlying disease. We report a patient with occipital brain infarction. The combination of age, gender, general malaise and elevated erythrocyte sedimentation rate led to the clinical suspicion of giant cell arteritis. Vertebral artery vasculitis was confirmed by 18-FD G positron emission tomography, combined with CT angiography, and immediate immunosuppressive therapy was started. Symptoms of stroke should, in a particular clinical context, raise suspicion of giant cell arteritis.

Deep white matter hyperintensities, decreased serum low-density lipoprotein, and dilative large arteriopathy.

Deep white matter hyperintensities (DWMHs) seen on magnetic resonance imaging (MRI) are thought to reflect small-vessel diseases (SVDs) and may have a background that differs from that of stenotic large-vessel diseases. We assessed risk factors for DWMHs and investigated the association between DWMHs and dilative changes in the basilar artery (BA) on MRI in nonstroke patients. We reviewed clinical information and MRI findings for 149 outpatients aged 46-90 years, excluding those with a previous symptomatic cerebrovascular event. DWMHs were graded 0-3, and the maximal BA diameter and area were measured from the flow void on axial T2-weighted MRI to assess dilatation. We divided the patients into groups with and without DWMH grade 2 or 3, and compared clinical information and BA parameters in these groups. The two groups demonstrated significant differences in age, serum low-density lipoprotein (LDL) level, estimated glomerular filtration rate (eGFR), and BA parameters. An adjusted logistic regression analysis including BA diameter found that age (odds ratio [OR], 1.974 per 10 years; 95% confidence interval [CI], 1.030-1.112; P = .0006), LDL (OR, 0.811 per 10 mg/dL; 95% CI, 0.964-0.965; P = .0085), eGFR (OR, 0.835 per 10 mL/min/1.73 m(2); 95% CI, 0.967-0.998; P = .0229), and BA diameter (OR, 2.515 per 1 mm; 95% CI, 1.191-4.098; P = .0119) were independently associated with the presence of DWMHs. An analysis including the BA area yielded similar results. DWMHs are manifestations of SVDs and show a strong association with lower serum LDL level, lower eGFR, and BA dilatation.

The triglyceride:high-density lipoprotein-cholesterol ratio and steno-occlusive disease in the intracranial arteries.

The extent of carotid artery atherosclerosis correlates with increased plasma concentrations of total cholesterol (TC) and low-density lipoprotein-cholesterol (LDL-C) and with a decreased plasma concentration of high-density lipoprotein-cholesterol (HDL-C). However, emerging data suggest that a triglyceride (TG):HDL-C ratio may be a better predictor of vascular risk than the traditional lipid measures such as TC and LDL-C. The purpose of this study was to evaluate the association between TC, LDL-C, TG, HDL-C, and the TG:HDL-C ratio with steno-occlusive disease in the intracranial cerebral arteries. We analyzed the records of 361 stroke-free subjects who underwent brain magnetic resonance angiography as part of their voluntary health checks. The presence of a steno-occlusive lesion in the basilar artery (BA) and in the horizontal portion of the middle cerebral artery (MCA) was assessed using brain 3D time of flight magnetic resonance angiography. All patients had fasting lipid panels drawn. We categorized serum lipid indices into quartiles and logistic regression analyses were performed. No serum lipid index was associated with the prevalence of MCA disease; TC, LDL-C, and HDL-C concentrations were not correlated with the prevalence of BA disease. A TG concentration in the third quartile compared with the lowest quartile was associated with increased prevalence of BA disease. The TG:HDL-C ratios in the upper three quartiles compared with the lowest quartile were associated with increased prevalence of BA disease. In conclusion, the TG:HDL-C ratio is more highly associated with the intracranial steno-occlusive disease than any standard lipid measure.

Association of testosterone and sex hormone-binding globulin with metabolic syndrome and insulin resistance in men.

OBJECTIVE: We sought to assess the associations of testosterones and sex hormone-binding globulin (SHBG) with metabolic syndrome and insulin resistance in men. RESEARCH DESIGN AND METHODS: We defined metabolic syndrome according to the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults. Among men aged >or=20 years who participated in the Third National Health and Nutrition Examination Survey (n = 1,226), the Cox proportional hazards model was used to estimate the prevalence ratio and 95% CI of metabolic syndrome according to circulating concentrations of testosterones and SHBG. RESULTS: After adjustment for age, race/ethnicity, smoking status, alcohol intake, physical activity level, LDL cholesterol, C-reactive protein, and insulin resistance, men in the first quartile (lowest) (prevalence ratio 2.16 [95% CI 1.53-3.06]) and second quartile of total testosterone (2.51 [1.86-3.37]) were more likely to have metabolic syndrome than men in the fourth quartile (highest, referent group) (P < 0.001 for linear trend). Similarly, men in the first quartile of SHBG (2.17 [1.32-3.56]) were more likely to have metabolic syndrome than men in the fourth quartile (P = 0.02 for linear trend). No significant associations of calculated free testosterone (P = 0.31 for linear trend) and bioavailable testosterone (P = 0.11 for linear trend) with metabolic syndrome were detected after adjustment for all possible confounders. CONCLUSIONS: Low concentrations of total testosterone and SHBG were strongly associated with increased likelihood of having metabolic syndrome, independent of traditional cardiovascular risk factors and insulin resistance.

[Arterial blood gas abnormalities during attacks of dizziness]. / Bas dönmesi ataklari sirasinda arteryel kan gazi anormallikleri.

OBJECTIVES: We investigated arterial blood gas abnormalities in patients presenting with dizziness. PATIENTS AND METHODS: The study included 58 patients (39 females, 19 males; mean age 46 years; range 22 to 74 years) who presented during attacks of dizziness. The duration of vertigo complaints ranged from one day to 30 years. Arterial gas measurements were performed at presentation and one month after treatment. The patients were examined in five groups according to the diagnoses: Meniere's disease (n=14), benign paroxysmal positional vertigo (n=13), vertebrobasilar insufficiency (n=12), vestibular neuritis (n=4), and craniocervical myofascial syndromes (n=15). RESULTS: At presentation, pH was low (acidosis) in two patients (3.5%), and high (alkalosis) in 15 patients (25.9%). After treatment, all abnormal pH values returned to normal. Twenty-four patients had high or low HCO3- values. High HCO3- values persisted in three patients together with dizziness. Patients with vestibular neuritis had significantly higher PO2 values compared to those with craniocervical myofascial syndrome and vertebrobasilar insufficiency (p<0.05). However, one month after treatment, there were no significant differences between five groups with respect to PO2 levels (p>0.05). Consecutive blood gas measurements did not differ significantly within each diagnosis group (p>0.05). CONCLUSION: Our results suggest that arterial blood gas abnormalities may be related to vertigo attacks.

Effects of blood hyperviscosity on functional integrity in the brain stem: a brain stem evoked auditory potential study.

Clinical hemorheological and brain stem auditory evoked potential (BAEP) investigations were performed in patients with ischaemic brain stem stroke. Lesions were verified by MRI. 55 healthy persons with negative rheological and BAEP findings were used as controls (group A/1). 33 stroke patients with negative rheological parameters (group A/2) and 34 patients with hyperviscosity (group A/3) were also enrolled. In group A/3 bilateral pathological BAEP patterns were found, that could be explained by microcirculatory disturbances. 36 persons with verified blood hyperviscosity, but without neurological signs were also examined (group A/4). In this group, as in group A/3, either total lack of any waveforms, or a bilateral prolongation of wave III was observed. In 31 cases of group A/4, control BAEP was performed after effective haemodilution therapy, and 6-12 months later (group B/1). Here, normalization of rheological profile had a temporary beneficial effect on BAEP in 14 of 18 cases with former wave III prolongation, but had no effect on BAEP patterns in 13 cases, where lack of waves had been verified by the first investigation. These data suggest that hyperviscosity can result in subclinical pathological symmetric BAEP patterns, both in ischaemic stroke patients and in hyperviscosity patients without neurological symptoms.

Tissue plasminogen activator and plasminogen activator inhibitor in patients with acute ischemic stroke: relation to stroke etiology.

Recent studies suggest that high plasma levels of tissue-type plasminogen activator (tPA) and its inhibitor (plasminogen activator inhibitor-1, PAI-1) are markers of an increased risk of atherothrombotic ischemic events such as stroke and myocardial infarction. In this prospective study, we measured tPA antigen, PAI-1 antigen and activity, as well as tPA/PAI-1 complex in patients with acute stroke. Stroke subtypes were classified according to the TOAST criteria. From 132 consecutively screened patients, 89 (100%) were enrolled in this study, including 42 patients (47%) with large artery atherosclerosis (LAA), 32 (36%) with small vessel occlusion (SVO), and 15 (17%) with cardioembolism (CE). Nineteen age-matched neurologic patients without manifestations of cerebrovascular disease served as control subjects (CS). Patients with acute stroke had significantly higher plasma levels of tPA antigen (p < 0.001), PAI-1 antigen (p < 0.05) and PAI activity (p < 0.05) than patients in the control group. t-PA antigen, PAI activity and tPA/PAI-1 complex levels were similar regardless of stroke etiology. Only PAI-1 antigen was lower in patients with cardioembolic stroke than in stroke patients with LAA (p < 0.05). Plasma tPA antigen, PAI-1 antigen, and PAI activity are significantly increased in patients with acute ischemic stroke. Except for PAI-1 antigen, this increase appears not to be related to the underlying stroke etiology.

[A pain syndrome of compression-reflex origin: the mechanisms of its development and the means for its therapeutic management]. / Bolevoi sindrom kompressionno-reflektornogo geneza: mekhanizmy razvitiia i puti terapevticheskogo vozdeistviia.

Complex observation and treatment of 112 patients with compressive-reflex syndromes of cervical osteochondrosis with pain as the leading clinical manifestation resulted in elaboration of the scheme of its pathogenesis. The main links of pathological process development as well as their relationships were described. The main means and methods of the correction of algesic syndrome development were determined on the basis of both own investigations and literary data. The peculiarity of this study was the inclusion of Xydiphone (the Russian-made drug from complexons group) in pathogenetic therapy. Its positive medical effect in treatment of the disease described was established.

[Pathogenetic, diagnostic and treatment problems in the cerebral ischemic form of arterial hypertension]. / Nekotorye voprosy patogeneza, diagnostiki i lecheniia tserebro-ishemicheskoi formy arterial'noi gipertenzii.

By means of complex investigations we studied the influence of certain brain structures' ischemia caused by disorders of the blood flow through the extracranial arteries on the arterial pressure. We established close correlative dependence between degree of brachycephalic arteries occlusion, contents of biologically active agents in the blood outflowing from the brain (angiotonin-2, vasopressin, prostanoids, catecholamines) and value of systemic arterial pressure. We worked out diagnostic criteria of arterial hypertension cerebroischemic using angio- and dopplerography. We have also substantiated the principles of therapy including inhibitors of angiotonin-converting enzyme and selective blockaders of calcium canals.

[The use of xidifon in the vertebral artery syndrome during exacerbation]. / Primenenie ksidifona pri sindrome pozvonochnoi arterii v period obostreniia.

To remove painful attacks in patients with the vertebral artery syndrome, use was made of xidiphon. The two methods of its administration were developed: application and electrophoretic. 27 patients in the stage of the disease exacerbation were examined and then treated. Vertebrobasilar vessels were examined over time by REG. A study was made of the content of macroelements and trace elements in the area of the impaired vessel, of the status of the bulbar conjunctival vessels using a "ShchL-2" lamp, and of the changes in the psychovolitional sphere and lipid peroxidation. A positive analgesic effect was attained in 25 patients, making it possible to eliminate or diminish to a considerable measure the doses of analgesics.

Abnormal hemorheological parameters in vertebrobasilar-insufficiency.

Thirty-seven patients, aged 47 +/- 22 years, diagnosed suffering from vertebrobasilar insufficiency (VBI), underwent a hemorheological examination; 20% of these patients had no vascular risk-factor but none showed complete normal hemorheological findings. The distribution of hemorheological parameters was comparable to those in patients suffering from stroke or TIA. Abnormal were platelet-reactivity in 78%, plasma-viscosity in 57%, fibrinogen in 23%, red-blood-cell-aggregation in 13% and hematocrit in 11% of all cases. To obtain more information on how to classify common clinical symptoms i.e. headache in combination with vertigo it may be useful to introduce hemorheological parameters as platelet-reactivity, plasma-viscosity, fibrinogen, in the further laboratory examination of those patients.

[Angiographic diagnosis and rheologic properties of blood in vertebrobasilar insufficiency caused by scalenus anticus syndrome]. / Angiograficheskaia diagnostika i reologicheskie svoistva krovi pri vertebrobaziliarnoi nedostatochnosti, obuslovlennoi skalenus-sindromom.

A study of 132 patients, aged 15 to 40 years, with bilateral scalenus syndrome, accompanied by vertebrobasilar insufficiency, is reported. The diagnostic value was assessed on the basis of 164 angiograms and 408 blood rheologic parameters. Selective arteriography, conducted simultaneously with the compression test and endovascular pressure gradient measurement, yields the most exhaustive and reliable data on the topical cause of the circulatory disturbance within the subclavian artery and its branches. The scalenus syndrome is an important etiologic factor of vertebrobasilar insufficiency. Intermittent flow through the vertebral artery results from ostium compression, spasm or increased flow in one of the vertebral arteries that may be due to an abnormal flexure, local pressure rise or high arcuation of the subclavian arterial segments I and II. Regional disorders of blood rheologic properties are also in evidence. Surgical treatment produces stable good results.