bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Nitroglycerin on Vasospasm and Cyclic Nucleotides in a Primate Model of Subarachnoid Hemorrhage
Authors: Nakao Koji , Murata Hiroto , Kanamaru Kenji , Waga Shiro
Published: June 2011

Background and Purpose
Nitroglycerin, as well as nitric oxide, causes hyperpolarization and cGMP elevation in vascular smooth muscle cells. It is unknown whether nitroglycerin ameliorates vasospasm by an increase in cGMP levels after subarachnoid hemorrhage (SAH). The purpose of the present study was to measure the levels of both cGMP and cAMP in the cerebral arteries and parietal cerebral cortices in a primate model and to determine the effect of nitroglycerin on vasospasm after SAH.

Methods
Chronic vasospasm was induced by clot placement around the right middle cerebral artery (MCA). Seven days after the surgery, angiography was repeated and either nitroglycerin (3 μg/kg per hour) or saline was administered intravenously. Angiography and regional cerebral blood flow (rCBF) measurements in the bilateral parietal cortices were performed before and after each treatment. Both cGMP and cAMP levels were measured in the cerebral arteries and bilateral parietal cortices.

Results
A significant vasospasm occurred in the cerebral arteries on both sides, more prominently on the right side. Concomitantly, rCBF on the right side was significantly decreased (
P
<.05). In the right MCA, cGMP levels were significantly lower than in the normal MCA (
P
<.05). After the administration of nitroglycerin for 3 hours, the cerebral vessels were significantly dilated on both sides (
P
<.05), and rCBF was significantly increased on the right side (
P
<.05) but not on the left side. Although depressed cGMP levels in the right MCA were not recovered by nitroglycerin, a significant increase in cGMP levels was observed in the basilar artery (
P
<.05). In both parietal cortices, cGMP levels were significantly decreased after SAH (
P
<.05) and unchanged after nitroglycerin treatment. There were no significant changes in cAMP levels in SAH and after nitroglycerin treatment.

Conclusions
The vasodilator effect of nitroglycerin in spastic MCA may not be mediated by an increase in cGMP levels, suggesting an involvement of hyperpolarization of the smooth muscle cells. Given the increase in rCBF, nitroglycerin may be therapeutic for the treatment of vasospasm.
What Role Do Neurologists Play in Determining the Costs and Outcomes of Stroke Patients?
Authors: Mitchell Janet B. , Ballard David J. , Whisnant Jack P. , Ammering Carol J. , Samsa Gregory P. , Matchar David B.
Published: June 2011

Background and Purpose
Despite growing concern over the large numbers of specialists in the United States, little information is available on how stroke treatment varies by the specialty of the attending physician. This study compares the costs and outcomes of acute stroke patients by physician specialty, especially between neurologists and other specialists.

Methods
We selected a random sample of Medicare patients aged 65 years and older admitted with cerebral infarction between January 1 and September 30, 1991, identified from the principal diagnosis on Medicare Provider Analysis and Review records. All Medicare claims for these patients were extracted from the date of admission through 90 days. The attending physician was identified as that physician billing for routine hospital visits during the first 7 days of the stay.

Results
Neurologists treating stroke patients were significantly more expensive than other physicians but obtained better outcomes. Ninety-day mortality rates for patients treated by neurologists were significantly lower than those for other specialists. These cost and outcome differences persisted even after adjustment for patient age, comorbidity, hospital teaching status, and other characteristics. Compared with other attending physicians, neurologists were significantly more likely to order diagnostic cerebrovascular tests (especially brain MRI scans), more likely to prescribe warfarin, and more likely to discharge patients to inpatient rehabilitation facilities.

Conclusions
Systematic triaging to neurologists based on clinical characteristics unmeasured by administrative data might explain these observed differences between neurologists and other physicians. Alternatively, these specialists may have been better able to identify the mechanism of stroke, information that then affected the course of treatment. Given current pressures to substitute generalists for specialists, however, more research is needed on these stroke treatment differences.
Hospital Services for Stroke Care
Authors: Beech Roger , Ratcliffe Mark , Tilling Kate , Wolfe Charles
Published: June 2011

Background and Purpose
Stroke is a common cause of mortality and morbidity in Europe and a major consumer of healthcare costs. However, outcomes from stroke vary significantly across Europe, raising the issue of the extent to which the delivery of care varies across Europe.

Methods
A multicenter, multinational study collected data on hospital admissions for stroke. These included patient baseline characteristics, clinical status, and use of inpatient services.

Results
Initial results examined inpatient services in nine hospitals in six countries. Statistically significant differences existed between hospitals in key processes of care, most notably in the areas of (1) mean length of stay (11 to 39 days) and median length of stay (8 to 21 days), (2) percentage of admissions receiving brain imaging (30% to 98%) and neurosurgery (0% to 31%), and (3) percentage of admissions with an identified “need” who received physiotherapy (44% to 90%) and occupational (0% to 65%) and speech (0% to 59%) therapy. Although there were significant hospital differences (
P
<.001) in the case mix of admissions in terms of level of consciousness, presence of incontinence, prestroke Rankin Scale score, and age, these did not explain the differences in care across sites.

Conclusions
There is geographic inequity across Europe in the care a stroke patient can expect to receive. Ongoing analysis will examine the link between European variations in service use and outcomes, in terms of mortality, handicap, and functional ability, as a means of indicating which patterns of care are the most effective.
Angioplasty and Stenting for Restenosis After Carotid Endarterectomy
Authors: Yadav Jay S. , Roubin Gary S. , King Peter , Iyer Sriram , Vitek Jiri
Published: June 2011

Background and Purpose
Endarterectomy for recurrent carotid stenosis after endarterectomy has a significantly higher complication rate than the original operation. Angioplasty and stenting may offer a useful alternative treatment for these patients.

Methods
Between September 1994 and April 1996, 22 patients had 25 carotid arteries treated with angioplasty and stenting for postendarterectomy restenosis. All patients had an independent neurological examination and National Institutes of Health Stroke Scale evaluation before and after the procedure. Patients were treated with aspirin and ticlopidine. All patients were requested to return at 6 months for follow-up angiography. The mean patient age was 69±7 years, and the mean elapsed time from endarterectomy was 73±69 months. Seventy-seven percent of the patients were symptomatic.

Results
Mean stenosis was reduced from 79±13% before the procedure to 1.8±3.6% after stenting. One patient had a minor stroke, for a complication rate of 4% per treated artery. In the eight patients who returned for 6-month angiography, mean stenosis was 19.4±4.4% and restenosis (≥50% stenosis) did not occur.

Conclusions
In a small series, angioplasty and stenting appear to be safe and well tolerated for the treatment of postendarterectomy restenosis.
PPBP [4-Phenyl-1-(4-phenylbutyl) Piperidine] Decreases Brain Injury After Transient Focal Ischemia in Rats
Authors: Takahashi Hiroshi , Kirsch Jeffrey R. , Hashimoto Kenji , London Edythe D. , Koehler Raymond C. , Traystman Richard J.
Published: June 2011

Background and Purpose
We tested the hypothesis that intravenous administration of the potent σ-receptor ligand 4-phenyl-1-(4-phenylbutyl) piperidine (PPBP) during transient focal ischemia would decrease postischemic brain infarction volume in rats.

Methods
Rats underwent intravascular focal ischemia for 2 hours followed by 22 hours of reperfusion. Halothane anesthesia was used only during initiation and cessation of ischemia. Rats received saline (n=10) or 1 μmol/kg per hour PPBP (n=10) by continuous intravenous infusion starting 1 hour after the initiation of ischemia and continuing through 22 hours of reperfusion.

Results
There was no difference between groups in blood pressure, arterial blood gas values, and body temperature. Triphenyltetrazolium-determined infarction volume of ipsilateral cerebral cortex (saline, 39±6%; PPBP, 21±7% of ipsilateral hemisphere; mean±SEM) and striatum (saline, 68±6%; PPBP, 33±8% of ipsilateral striatum) was smaller in rats treated with PPBP than in rats treated with saline.

Conclusions
These data indicate that σ-receptors may play an important role in the mechanism of injury both in cortex and striatum after 2 hours of transient focal ischemia in rats. Because PPBP afforded protection when administered at the end of ischemia and during reperfusion, σ-receptors may influence the progression of injury in ischemic border regions.
Selective N-Type Calcium Channel Antagonist Omega Conotoxin MVIIA Is Neuroprotective Against Hypoxic Neurodegeneration in Organotypic Hippocampal-Slice Cultures
Authors: Pringle A.K. , Benham C.D. , Sim L. , Kennedy J. , Iannotti F. , Sundstrom L.E.
Published: June 2011

Background and Purpose
Neuroprotection by antagonists of both L-type and N-type calcium channels occurs in in vivo models of ischemia. The site of action of calcium channel antagonists is unclear, however, and it is likely that a combination of vascular and direct neuronal actions occurs. We have investigated the effects of blocking neuronal calcium channels using an organotypic hippocampal-slice model of ischemia.

Methods
Organotypic hippocampal-slice cultures prepared from 10-day-old rats were maintained in vitro for 14 days. Cultures were exposed to either 3 hours of oxygen deprivation (hypoxia) or 1 hour of combined oxygen and glucose deprivation (ischemia). Neuronal damage was quantified after 24 hours by propidium iodide fluorescence.

Results
Three hours of anoxia produced damage exclusively in CA1 pyramidal cells. This damage was prevented by preincubation with omega conotoxin MVIIA, a selective N-type calcium channel blocker, and omega conotoxin MVIIC, which blocks N-type and other presynaptic neuronal calcium channels. The dihydropyridine nifedipine and the mixed calcium channel blocker
SB201823
-A were not protective. Furthermore, if addition of conotoxin MVIIA was delayed until after the hypoxic episode, a dose-dependent neuroprotective effect was observed, with an IC
50
of 50 nmol/L. In contrast to hypoxia, none of the compounds was neuroprotective in the model of oxygen-glucose deprivation, although it was determined that extracellular calcium was essential for the generation of ischemic damage.

Conclusions
These studies present clear evidence that neuroprotection by selective N-type calcium channel antagonists is mediated directly through neuronal calcium channels. In contrast, the neuroprotective effects of dihydropyridines may be mediated through vascular calcium channels or indirectly through actions in other brain regions.
Angiogenic Factors in Moyamoya Disease
Authors: Yoshimoto Tetsuyuki , Houkin Kiyohiro , Takahashi Akihiro , Abe Hiroshi
Published: June 2011

Background and Purpose
We previously reported that the level of basic fibroblast growth factor (bFGF) is high in cerebrospinal fluid (CSF) taken from patients with moyamoya disease. The present study investigated the levels of other angiogenic growth factors in the CSF of moyamoya patients and the clinical significance of bFGF in moyamoya disease.

Methods
The levels of bFGF, interleukin-8, platelet-derived growth factor, transforming growth factor-β, endothelial growth factor, and vascular endothelial cell growth factor in CSF, taken from 38 patients with moyamoya disease and 16 patients with atherosclerotic occlusive disease (control group), were measured by an enzyme-linked immunosorbent assay. We analyzed the correlation between the level of bFGF and the clinical factors of age, onset pattern, development of neovascularization, and cerebral circulation.

Results
The CSF of moyamoya patients contained a high concentration of bFGF to a significant (
P
<.05) extent. The bFGF level was apparently elevated in the patients in whom neovascularization from indirect revascularization, such as encephaloduroarteriosynangiosis, was well developed (
P
<.01). A linear correlation between the values of bFGF and cerebral vascular response to acetazolamide (
r
=.7;
P
<.05) was revealed. The other angiogenic factors were not significantly high compared with the control group.

Conclusions
The elevation of bFGF in moyamoya disease seems to be specific and is not related simply to cerebral ischemia. Clinically, the bFGF level is a useful indicator to predict the efficacy of indirect revascularization after surgery.
Association of Chlamydial Infection With Cerebrovascular Disease
Authors: Wimmer Martin L.J. , Sandmann-Strupp Ruth , Saikku Pekka , Haberl Roman L.
Published: June 2011

Background and Purpose
Recent studies suggest an association of coronary heart disease and carotid atherosclerosis with
Chlamydia pneumoniae
infection. We investigated the frequency of chlamydial seropositivity and specific circulating immune complexes in patients with recent cerebrovascular disease.

Methods
Specific antibodies to
C pneumoniae
in serum were measured by the microimmunofluorescence test in 58 consecutive patients (aged 18 to 50 years) with ischemic infarction (n=39) or transient ischemic attacks (n=19) and in 52 hospital control subjects without vascular disease, matched for sex, age, time, and locality.

Results
Twenty-seven patients (46.6%) and 12 control subjects (23.1%) had raised IgA titers ≥1:16 (
P
=.018). IgG titers ≥1:32 were measured in 74.1% of the patients and 77% of control subjects (
P
=.623). Specific IgG antibodies in circulating immune complexes, which were isolated by polyethylene glycol precipitation, were elevated ≥1:8 in 24.1% of the patients and 7.7% of control subjects (
P
=.047). With the use of a conditional logistic regression model, the odds ratios were 1.70 (95% confidence interval [CI], 1.13 to 2.58) for elevated IgA titers, 1.91 (95% CI, 1.06 to 3.47) for the presence of immune complexes, and 1.96 (95% CI, 1.00 to 3.82) for the presence of both factors. After adjustment for the vascular risk factors hypertension, age, sex, and migraine, the odds ratios were 1.71 (95% CI, 1.08 to 2.70), 2.00 (95% CI, 1.07 to 3.76), and 2.20 (95% CI, 1.09 to 4.41), respectively.

Conclusions
We conclude that chronic infection with
C pneumoniae
is associated with an increased risk of stroke and transient ischemic events.
Patent Foramen Ovale and Transcranial Doppler
Authors: Zanette Elietta Maria , Mancini Giovanni , De Castro Stefano , Solaro Marco , Cartoni Domenico , Chiarotti Flavia
Published: June 2011

Background and Purpose
The capability of transcranial Doppler sonography (TCD) to detect a patent foramen ovale (PFO) has been established. However, which provocative maneuver and what timing of contrast injection are most effective to induce a right-to-left shunt has not yet been determined.

Methods
We selected 38 cerebrovascular patients (21 men, 17 women) with positive contrast study for PFO on transesophageal echocardiography. Patients underwent a TCD with bilateral monitoring of the middle cerebral arteries (MCAs) and injection of a contrast solution. The injection was repeated (1) during normal breathing (basal conditions); (2) before Valsalva maneuver (VM); (3) during VM; (4) immediately after VM; and (5) during cough. The latency time and the total number of microbubbles for each side were recorded.

Results
TCD found positive results for PFO in 30 patients. Twenty were positive even during basal conditions. The number of positive cases varied according to the timing of the VM in relation to the contrast injection: 28, 25, and 27 cases were positive when the injection was performed before, during, and after VM, respectively, while 26 were positive during cough. There were significant differences in the number of microbubbles in the MCAs between the procedures (
P
<.001, ANOVA): the highest number was detected in the injection before VM and the lowest number during basal conditions (
P
<.001, Wilcoxon's test with Bonferroni's correction). The latency time was significantly shorter when the injection followed VM.

Conclusions
The injection performed before VM appeared to be the most effective TCD procedure in determining the transit of microbubbles through a PFO and subsequently in the MCAs.
Visually Evoked Blood Flow Response Assessed by Simultaneous Two-Channel Transcranial Doppler Using Flow Velocity Averaging
Authors: Sturzenegger Matthias , Newell David W. , Aaslid Rune
Published: June 2011

Background and Purpose
We assessed the influence of different visual stimuli and the reproducibility and habituation of evoked flow responses using simultaneous two-channel transcranial Doppler monitoring and flow velocity averaging.

Methods
We measured stimulus-related percentage changes in posterior cerebral, basilar, and middle cerebral artery blood flow velocities in 14 normal volunteers using stimulus-triggered velocity averaging. With a two-channel transcranial Doppler system, simultaneous measurements in two arteries (both posterior cerebral arteries and the basilar and middle cerebral artery) were taken using multiple-array light-emitting diodes applying flash stimuli. Both posterior cerebral arteries were monitored to assess reproducibility and habituation of the evoked response with repetitive measurements under unchanged conditions and to analyze the influence of different features of the visual stimulus.

Results
There was a distinctive increase in velocities resulting from visual stimuli in both posterior cerebral and the basilar arteries but not in the middle cerebral artery. The responses in both posterior cerebral arteries were larger than in the basilar artery (
P
=.0001). Brightness (
P
<.0001), as well as complexity (
P
<.0001), of the visual stimulus had a significant influence on the response amplitude. There was a trend toward a greater right-sided activation. Amplitudes of the evoked response were very stable during repetitive testing (coefficient of variation of the difference was 0.6). There was a trend toward habituation with monotonous (flash) but not with complex visual stimuli. A “zero” stimulus produced no responses.

Conclusions
The use of flow velocity averaging and two-channel simultaneous recording increases the sensitivity of transcranial Doppler monitoring to detect and correlate selective flow changes in the posterior cerebral arteries resulting from cerebral activation produced by visual stimulation.
Presence and Severity of Cerebral White Matter Lesions and Hypertension, Its Treatment, and Its Control
Authors: Liao Duanping , Cooper Lawton , Cai Jianwen , Toole James F. , Bryan Nick R. , Hutchinson Richard G. , Tyroler Herman A.
Published: June 2011

Background and Purpose
White matter lesions (WML) may result from cerebral hypoperfusion or ischemia. We investigated the association of WML with blood pressure, hypertension, and its treatment and control.

Methods
A random sample of 1920 participants aged 55 to 72 years in the Atherosclerosis Risk in Communities Study (ARIC) was examined. Spin-density 1.5-T MRI scan images were coded from 0 for normal to 9 for most severe WML. Hypertension was defined as systolic or diastolic pressure ≥140/90 mm Hg or use of antihypertensive medication.

Results
The percentages of persons with WML grades 0 through 2 and 3 through 9, respectively, were as follows: normotensive, 92.4% and 7.6%, versus all hypertensive subjects, 83% and 17% (
P
<.001); and treated controlled hypertensive, 86% and 14%, versus treated uncontrolled hypertensive subjects, 76% and 24% (
P
=.003). Multivariable adjusted odds ratios (95% confidence intervals) for WML grade ≥3 relative to normotensive subjects was 2.34 (1.71 to 3.20) for all hypertensives, 1.99 (1.19 to 3.08) for untreated hypertensives, 1.94 (1.32 to 2.85) for treated controlled hypertensives, and 3.40 (2.30 to 5.03) for treated uncontrolled hypertensives. After additional adjustment for hypertension duration, treatment, and control status, the odds ratios (95% confidence intervals) for a 1 SD increase of systolic and diastolic blood pressure were 1.43 (1.11 to 1.85) and 1.16 (0.94 to 1.43), respectively.

Conclusions
Hypertension is associated with increased odds of WML, and treated uncontrolled hypertensive subjects have greater odds of WML than those with treated controlled hypertension. The data suggest that the level of blood pressure, especially systolic blood pressure, is related to WML, additional to the effects of categorically defined hypertension and its treatment and control status.
Delayed Postischemic Hyperthermia in Awake Rats Worsens the Histopathological Outcome of Transient Focal Cerebral Ischemia
Authors: Kim Young , Busto Raul , Dietrich W. Dalton , Kraydieh Susan , Ginsberg Myron D.
Published: June 2011

Background and Purpose
Over the past several years, it has been demonstrated that mild intraischemic or immediate postischemic hyperthermia worsens ischemic outcome in models of global and focal ischemia. Periods of hyperthermia are commonly seen in patients after stroke and cardiac arrest. The hypothesis tested in this study was that a brief hyperthermic period, even when occurring days after an ischemic insult, has detrimental effects on the pathological outcome of focal ischemia.

Methods
Rats were subjected to 60 minutes of transient middle cerebral artery occlusion by insertion of an intraluminal filament. Twenty-four hours after reperfusion, awake rats were subjected to temperature modulation for 3 hours in a heating chamber. The brain temperature was equilibrated to either 37°C to 38°C, 39°C, or 40°C. Changes in rectal temperature and blood glucose concentration were evaluated during and just after temperature modulation. Behavioral tests were also assessed. Three days after temperature modulation, brains were perfusion-fixed, and infarct volumes were determined.

Results
In animals with 40°C hyperthermia, cortical and total infarct volumes were markedly greater (92.2±63.1 and 126.5±72.3 mm
3
[mean±SD], respectively) than in normothermic rats (14.4±12.7 and 42.4±19.2 mm
3
) and in animals with 39°C hyperthermia (16.5±28.7 and 40.9±34.3 mm
3
) (
P
<.05), whereas there was no significant difference between normothermic and 39°C hyperthermic animals. In addition, animals with 40°C hyperthermia displayed worsened neurological scores compared with normothermic and 39°C hyperthermic rats. In the 39°C hyperthermia group, rectal temperatures were significantly lower (by 0.2°C to 0.5°C) than brain temperatures throughout the modulation period.

Conclusions
The present findings provide evidence that, after a transient focal ischemic insult, the postischemic brain becomes abnormally sensitive to the effects of delayed temperature elevation, even of moderate degree. The threshold for aggravation of ischemic injury by delayed hyperthermia appears to be approximately 40°C. Body-temperature measurements, in both awake and anesthetized animals, may not accurately reflect brain temperature under these conditions. The present study stresses that fever of even moderate degree in the days following brain ischemia may markedly exacerbate brain injury.
Pressure-Induced Myogenic Responses in Human Isolated Cerebral Resistance Arteries
Authors: Wallis Sarah J. , Firth John , Dunn William R.
Published: June 2011

Background and Purpose
Pressure-induced myogenic responses have been demonstrated in cerebral resistance arteries isolated from a number of species. In the present study, we determined the response of human isolated cerebral resistance arteries to a pressure stimulus.

Methods
Arteries were set up in a pressure myograph and exposed to alterations in intravascular pressure.

Results
Human isolated cerebral resistance arteries developed spontaneous intrinsic tone in response to a pressure stimulus over the pressure range of 20 to 90 mm Hg that was not apparent in the absence of extracellular calcium. This intrinsic tone may be an inherent property of the vascular smooth muscle, since it remained after functional removal of the endothelium.

Conclusions
Human isolated cerebral resistance arteries spontaneously contract when exposed to raised intravascular pressure. This pressure-induced myogenic response may contribute to cerebral autoregulation of blood flow.
Disorders of Smell, Taste, and Food Intake in a Patient With a Dorsomedial Thalamic Infarct
Authors: Rousseaux M. , Muller P. , Gahide I. , Mottin Y. , Romon M.
Published: June 2011

Background
We report that a lasting deficit in the hedonic character of olfactory and gustatory perception can be observed in bilateral dorsomedial and intralaminar thalamic lesions.

Case Description
A 68-year-old patient abruptly presented with vigilance disorders associated with a reduction of olfactory and gustatory perceptions. A severe drop in appetite for foods and a weight loss of 10 kg were observed, which were partially reversed with time. Two years later, the main persisting disorder was a change in the quality of perceptions: odors and taste were perceived either in a neutral way, their pleasant character having disappeared, or as unpleasant. However, identification was preserved. MRI showed that lesions principally involved the dorsomedial thalamic nuclei and the adjacent part of the intralaminar nuclei.

Conclusions
This case suggests that the dorsomedial thalamus may play a role in the hedonic perception of food, thus affecting short-term regulation of food intake, and may possibly have a role in the long-term control of body weight.
Changed Incidence and Case-Fatality Rates of First-Ever Stroke Between 1970 and 1993 in Tartu, Estonia
Authors: Kôrv Janika , Roose Mai , Kaasik Ain-Elmar
Published: June 2011

Background and Purpose
The incidence of stroke has stabilized or increased in several developed countries recently, but few data about the trends are available from Eastern Europe. The study was designed to evaluate the possible changes of stroke incidence in Estonia.

Methods
A population-based stroke registry was conducted in Tartu during 1991 through 1993 (mean population, 110 631) to compare it with the study of 1970 through 1973 (population, 90 459). The majority of stroke patients were recorded prospectively, and most were hospitalized and evaluated by a neurologist. All available medical records were reviewed. Only first-ever stroke cases were registered.

Results
A total of 667 patients in 1970 through 1973 and 829 patients in 1991 through 1993 were recorded. The total annual incidence per 100 000 rose from 221 to 250 (
P
=.0173). The total rate for men increased nonsignificantly from 183 to 209 and for women from 258 to 284. Significant increases were observed for men aged 50 to 59 years and for women aged 50 to 69 years; for persons over 70 years, the rates slightly declined. The case-fatality rate at 1 month declined significantly, from 49% to 30%.

Conclusions
A remarkable increase in the incidence and decline in the case-fatality rate of first-ever stroke was observed in Tartu, Estonia. The increase of incidence for those younger than 70 years could be due to the increased prevalence of risk factors. The decline in case fatality could theoretically be related to better management of secondary complications.
Fish Consumption and Stroke in Men
Authors: Orencia Anthony J. , Daviglus Martha L. , Dyer Alan R. , Shekelle Richard B. , Stamler Jeremiah
Published: June 2011

Background and Purpose
Evidence of a relationship of fish intake to stroke incidence or mortality is weak. This report examines the association of fish consumption with stroke.

Methods
A cohort of 2107 men aged 40 to 55 years from the Chicago Western Electric Study who were free of coronary heart disease and stroke through their first annual reexamination was investigated in relation to baseline fish intake and 30-year risk of fatal and nonfatal stroke. Data on baseline fish intake, categorized into four levels (≥35 g/d, 18 to 34 g/d, 1 to 17 g/d, and 0 g/d), were available for 1847 men. Average values of macronutrients and micronutrients from the first two examinations and major coronary and stroke risk factors were assessed in relation to fish consumption. Stroke mortality was ascertained from death certificates and nonfatal stroke from records of the Health Care Financing Administration.

Results
During 46 426 person-years of follow-up, 76 stroke deaths occurred. Men consuming ≥35 g/d of fish (highest level) had a higher age-adjusted death rate from stroke (23.5 per 10 000 person-years) than men in the three other categories of fish consumption. Based on a Cox proportional hazards regression model with adjustment for age, systolic blood pressure, cigarette smoking, serum cholesterol level, diabetes, electrocardiographic abnormalities, and table salt use, hazards ratios (and 95% confidence intervals) for fish consumers compared with nonconsumers were 1.34 (0.53 to 3.41) for ≥35 g/d, 0.96 (0.41 to 2.21) for 18 to 34 g/d, and 1.00 (0.43 to 2.33) for 1 to 17 g/d. Age-adjusted and multivariate analyses for fatal and nonfatal strokes (n=222) yielded similar results.

Conclusions
With stroke rates highest in the subgroup reporting highest fish intake, these data do not support the hypothesis of an inverse association of fish consumption with strokes.
Diabetes Mellitus as a Risk Factor for Death From Stroke
Authors: Tuomilehto Jaakko , Rastenytė Daiva , Jousilahti Pekka , Sarti Cinzia , Vartiainen Erkki
Published: June 2011

Background and Purpose
High blood pressure is the most important risk factor for stroke. It is also known that diabetic patients are at increased risk of both hypertension and stroke. The aim of this study was to assess the independent effect of diabetes as a risk factor for stroke. Results from the previous studies of this question have been somewhat inconclusive.

Methods
We performed a prospective study (average follow-up, 16.4 years) of 8077 men and 8572 women who had participated in risk factor surveys in Eastern Finland in 1972 (20 years of follow-up) and 1977 (15 years of follow-up). Risk factors included in the current analyses were smoking, blood pressure, antihypertensive drug treatment, serum total cholesterol, and diabetes either at baseline or developed during the follow-up. Age- and risk factor-adjusted relative risks for death of stroke were determined with the Cox proportional hazards model.

Results
Diabetes mellitus was the strongest risk factor for death from stroke among both men and women in univariate and multivariate analyses. In addition, smoking and systolic blood pressure appeared to be independent risk factors among both sexes, as did serum total cholesterol among men. Men with diabetes at baseline appeared to be at a sixfold increased risk of death from stroke, while relative risk for men who developed diabetes during the follow-up was 1.7. In women, those who were diabetic at baseline were at higher risk of stroke than women who developed diabetes later (relative risks, 8.2 and 3.7, respectively). Of stroke deaths, 16% in men and 33% in women were attributed to diabetes.

Conclusions
Diabetic subjects have a very high risk of death from stroke, particularly women. Our data also suggest that the duration of diabetes is an important factor contributing to the risk of stroke.
Craniotomy for Intracranial Aneurysm and Subarachnoid Hemorrhage
Authors: Stachniak Joseph B. , Layon A. Joseph , Day Arthur L. , Gallagher T. James
Published: June 2011

Background and Purpose
Age may influence cost or effectiveness of treatment for subarachnoid hemorrhage (SAH). This study examined the effect of age on both.

Methods
Patients (n=219) who underwent craniotomy for intracranial aneurysm and SAH over 6 years at one tertiary care center were divided in two ways by age: single advanced age (<65 years and ≥65 years) and decade of age (23 to 39, 40 to 49, 50 to 59, 60 to 69, and 70 to 81 years). Data recorded for each patient included numbers of procedures and complications in the surgical intensive care unit (SICU), number of days in the SICU and the hospital, costs for SICU and ward care, total cost (SICU plus ward costs), and the Acute Physiology and Chronic Health Evaluation (APACHE) II score at admission and discharge, the Hunt-Hess grade at admission and immediately preoperatively, and quality of life score, a measure of outcome. Mortality rates by age group were calculated.

Results
The only variable significantly affected by decade of age was mortality rate, which increased as decade of age increased (3% to 17%). With the 65-year comparison, mortality rate, cost, APACHE II score at admission and discharge, days before operation, and days in the SICU were significantly higher for age ≥65 years.

Conclusions
Whereas mortality is higher for the older age group, quality of life scores appear acceptable for those who survive. Even though the hospital costs of treating elderly patients for SAH may be higher than those for younger patients, this should not be used to justify withholding care from the elderly.
Assessment of the Posterior Communicating Artery by Transcranial Color-Coded Duplex Sonography
Authors: Klötzsch Christof , Popescu Octavian , Berlit Peter
Published: June 2011

Background and Purpose
The aim of this study was to investigate flow velocity and flow direction in the posterior communicating artery (PcomA) by means of transcranial color-coded duplex sonography (TCCD) and to compare the results with angiographic findings.

Methods
Thirty patients with unilateral occlusion of the internal carotid artery (ICA) due to atherosclerosis (n=15) or balloon occlusion (n=15) and 50 normal subjects were included. The circle of Willis was insonated through the temporal bone window. In 24 patients with unilateral ICA occlusion, angiograms were available and were compared with the results of TCCD.

Results
The PcomA could be detected unilaterally in 70% of normal subjects and bilaterally in 30%. A retrograde flow direction in the PcomA from the posterior cerebral artery to the ICA was found in 75% of the normal control subjects. The mean peak flow velocity in normal PcomAs was 36±15 cm/s (±SD). No significant differences in flow velocity were found between unilaterally and bilaterally detectable PcomAs or between retrograde and orthograde PcomAs. In patients with unilateral ICA occlusion we observed ipsilaterally a retrograde flow direction, with an elevation of flow velocity (64±10 cm/s) compared with the contralateral side (27±14 cm/s;
P
<.001).

Conclusions
TCCD appears to be a valuable method to determine flow velocity and flow direction not only in the large intracranial vessels but also in the smaller communicating arteries. In the future this method could be useful for the planning of ICA balloon occlusions and in deciding whether to perform extracranial/intracranial bypass surgery. It could furthermore show intracranial collaterals in patients with cerebrovascular disease and help to estimate the risk of watershed infarctions in patients with asymptomatic high-grade ICA stenosis and in patients undergoing carotid endarterectomy.
Dr C. Miller Fisher and the History of Carotid Artery Disease
Authors: Estol Conrado J.
Published: June 2011

Background and Purpose
Our aim was to analyze the role that C. Miller Fisher (C.M.F.) had in promoting an understanding of carotid artery disease (CAD). Although Chiari in 1905 and later Hunt, Moniz, and Hultquist, among others, described the association of CAD and stroke, this received little attention until C.M.F. published his clinicoanatomic correlations in “Occlusion of the Carotid Arteries.” Until then, some 55% of strokes were attributed to “vasospasm.”

Methods
We analyzed articles (“Occlusion of the Internal Carotid Artery,” 1951; “Occlusion of the Carotid Arteries,” 1954; “Transient Monocular Blindness Associated With Hemiplegia,” 1952; “The Microembolic Theory of Transient Ischemic Attacks,” 1976; “A Clinico-pathologic Study of Carotid Endarterectomy Plaques,” 1986) and conducted personal interviews with C.M.F.

Results
During the 1950s, C.M.F. described the clinical implications of transient ischemic attacks and their relationship to CAD and stroke. The last sentence in the 1951 article read: “Unexplained cerebral embolism may arise from thrombotic material lying in the carotid sinus.” In the same article he also wrote that “it is even conceivable that some day vascular surgery will find a way to by-pass the occluded portion of the artery during the period of ominous fleeting symptoms,” heralding the future surgical treatment of carotid artery disease. C.M.F. called attention to the commonness of carotid disease, described transient monocular blindness, and studied the relationship between plaque pathology and clinical findings.

Conclusions
C.M.F.’s clinicopathologic observations were a major factor in promoting recognition of the clinical features, stroke risk, and treatment of CAD.
Recurrent Spontaneous Arterial Dissections
Authors: Schievink Wouter I. , Mokri Bahram , Piepgras David G. , Kuiper James D.
Published: June 2011

Background and Purpose
Among patients with spontaneous cervical artery dissections, the risk of recurrent arterial dissection is relatively low at 1% per year, but this risk may be higher for patients with a family history of arterial dissections. We compared the risk of a recurrent arterial dissection in patients with familial versus nonfamilial disease.

Methods
Long-term follow-up was established in 200 patients (104 women and 96 men with a mean age of 44.9 years) with spontaneous cervical artery dissections evaluated at a single institution between 1970 and 1990.

Results
Among the 200 patients, 10 (5%) were identified who had a family history of spontaneous arterial dissections. In a multivariate analysis, family history was the only significant variable associated with the risk of recurrent dissection (χ
2
=15.51;
P
=.0001). A recurrent arterial dissection was identified in 5 (50%) of the 10 patients with familial disease compared with 11 (5.8%) of the 190 patients with nonfamilial disease, with an estimated relative risk of 6.3 (95% confidence interval, 2.2 to 18.3;
P
=.0007).

Conclusions
Among patients with spontaneous cervical artery dissections, a family history of arterial dissection is an important risk factor for the development of a recurrent arterial dissection.
Incidence of Subarachnoid Hemorrhage
Authors: Linn F.H.H. , Rinkel G.J.E. , Algra A. , van Gijn J.
Published: June 2011

Background and Purpose
The incidence of subarachnoid hemorrhage (SAH) has been estimated for many years at 10 to 15 per 100 000 person-years, but the most recent studies yield lower figures, of 6 to 8 per 100 000 person-years. To investigate the cause of this apparent decline, we studied the influence of year of study, rate of CT, and region.

Methods
We performed a meta-analysis of SAH incidence studies from 1960 onward and assessed the influence of the three factors by means of univariate and multivariate Poisson regression analyses.

Results
Eighteen studies fulfilled predefined inclusion criteria. In three Finnish studies, the pooled incidence was 21.4 per 100 000 person-years (95% confidence interval [CI], 19.5 to 23.4); in 15 non-Finnish studies, it was 7.8 per 100 000 person-years (95% CI, 7.2 to 8.4). With univariate analysis, in non-Finnish studies the incidence decreased 0.96% for each percentage point increase of patients investigated with CT (rate ratio, 0.9904; 95% CI, 0.9878 to 0.9930). With 100% CT scanning, the incidence of SAH outside Finland is estimated at 6 per 100 000 person-years. The rate ratio for year of study was 0.952 (95% CI, 0.935 to 0.969) for each later year in the period 1960 to 1994. In multivariate analysis, only the use of CT was independently related to SAH incidence. For the Finnish studies, the rate ratios for use of CT and year of study were not statistically significant. We also found in six studies that incidence for women was 1.6 (95% CI, 1.1 to 2.3) times higher than that for men (7.1 [95% CI, 5.4 to 8.7] and 4.5 [95% CI, 3.1 to 5.8], respectively).

Conclusions
The actual incidence of SAH has remained stable over the last three decades; the apparent decline in incidence is entirely explained by the greater proportion of patients investigated with CT. The incidence of SAH in Finland is almost three times as high as in other parts of the world.
Factors of Carotid Arterial Enlargement in a Population Aged 59 to 71 Years
Authors: Bonithon-Kopp Claire , Touboul Pierre Jean , Berr Claudine , Magne Christine , Ducimetière Pierre
Published: June 2011

Background and Purpose
Factors of carotid arterial enlargement are not well known in general populations. The purpose of this study was to assess the cross-sectional associations of arterial wall lesions and cardiovascular risk factors with carotid lumen diameter in elderly subjects.

Methods
B-mode ultrasound examinations of the carotid arteries and risk factor assessment were made in 1272 participants in the EVA (Etude sur le vieillissement artériel) Study, a longitudinal study designed to evaluate vascular and cognitive aging in men and women aged 59 to 71 years. Ultrasound examinations included measurements of intima-media thickness (IMT) and interadventitial and lumen diameters of the common carotid arteries and quantification of atherosclerotic plaques in extracranial carotid arteries.

Results
Men showed greater IMT and interadventitial and lumen diameters of the common carotid arteries than did women. In both sexes, common IMT and plaque score were positively associated with common interadventitial and lumen diameters. Stepwise multiple regression analysis showed that male sex, body height and weight, common IMT, plaque score, systolic blood pressure, and alcohol consumption were positively and independently related to lumen diameter. On the other hand, an independent negative association was observed between low-density lipoprotein cholesterol and lumen diameter.

Conclusions
In 59- to 71-year-old subjects, increased IMT and atherosclerotic plaques were accompanied by an increase in lumen diameter of the common carotid arteries, indicating an overcompensation. Luminal enlargement observed with several risk factors and with high blood pressure in particular might be partially counteracted by high lipid levels.
Validity of B-Mode Ultrasonographic Findings in Patients Undergoing Carotid Endarterectomy in Comparison With Angiographic and Clinicopathologic Features
Authors: Kagawa Reiko , Moritake Kouzou , Shima Takeshi , Okada Yoshikazu
Published: June 2011

Background and Purpose
Determining factors for performing carotid endarterectomy (CEA) are the severity of carotid stenosis and the presence of plaque ulcerations. Precise detection of these factors is important. The aim of this study was to assess the applicability of using B-mode ultrasonography for diagnosing carotid lesions in patients undergoing CEA.

Methods
B-mode examinations were performed on 64 Japanese patients (68 arteries) who subsequently underwent CEA. In each case, the appearance of plaque on B-mode was classified into one of two types: heterogeneous or homogeneous; plaque echogenicity was expressed as hypoechoic, isoechoic, or hyperechoic. Surface characteristics such as ulceration also were examined, and the degree of carotid artery stenosis was calculated. The B-mode findings were compared with angiographic and pathological features.

Results
B-mode accurately visualized macroscopic ulceration and surface irregularity in 93.8% of the lesions examined, which was superior to angiography. Fifty-four lesions (79.4%) were of the heterogeneous type and 14 lesions (20.6%) were of the homogeneous type on B-mode. Microscopically, 57.4% of the heterogeneous-type lesions were a mixture of atheroma and fibrosis, and all homogeneous-type lesions demonstrated fibrous change. The frequency of calcification was higher in the heterogeneous lesions than in the homogeneous lesions.

Conclusions
B-mode ultrasonography findings can provide information about macroscopic and microscopic characteristics of carotid lesions.
‘Medial Defects’ in the Prenatal Human Cerebral Arteries
Authors: Fujimoto Katsukuni
Published: June 2011

Background and Purpose
Fine structural studies were performed to investigate the histogenesis of human intracranial arteries. Special attention was paid to whether “medial defects” exist in these arteries.

Methods
Segments of the intracranial extracerebral arteries of normal human embryos (n=6) were examined with transmission electron microscopy.

Results
Focal defects of the medial smooth muscle cells were disclosed at every bifurcation of the developing arteries. This configuration persisted until the arteries obtained enough muscle coat. These areas, in which an absence of medial smooth muscle cells (ie, a medial defect) existed, were occupied by fibrous connective tissues of elastin and collagen.

Conclusions
The medial defect observed at the arterial bifurcation of the embryos seems to be a development process that accompanies human ontogenesis rather than a congenital anomaly, supporting a possible pathogenesis for intracranial saccular aneurysms.
Alterations of Regional Cerebral Blood Flow and Oxygen Saturation in a Rat Sinus-Vein Thrombosis Model
Authors: Nakase H. , Heimann A. , Kempski O.
Published: June 2011

Background and Purpose
The pathophysiology of sinus-vein thrombosis (SVT) in patients and experimental animals is still poorly understood. This study was designed to examine and further elucidate the pathophysiological sequence of events, especially the relationship between local and regional blood flow and hemoglobin oxygen saturation (HbSO
2
) detected at identical locations. The use of both parameters as outcome indicators should be compared.

Methods
SVT was induced by ligation of the superior sagittal sinus (SSS) and slow injection of kaolin-cephalin suspension into the SSS in rats. Regional cerebral blood flow (rCBF) was assessed by laser-Doppler flowmetry together with regional HbSO
2
, which was measured by a microspectrophotometric technique at 48 identical locations for 90 minutes after SVT using a scanning technique. Fluorescence angiography was performed before and 30 and 90 minutes after SVT induction. After 48 hours the animals were killed for histology.

Results
The fluorescence angiographic findings could divide animals into three groups: (1) group A, with a solitary SSS thrombus (n=8); (2) group B, with a thrombosis of SSS and cortical veins (n=10); (3) group C, animals that had undergone sham operation (n=5). Decreases of rCBF and HbSO
2
and brain damage were seen in group B but not in group A. The reduction of local HbSO
2
preceded the flow decrease after sagittal sinus ligation but before thrombosis. Blood pressure in group A was found to be significantly higher after SVT than in groups B and C.

Conclusions
The brain with acute extension of a thrombus from the SSS into cortical veins experiences a critically reduced supply of blood and oxygen. CBF, local HbSO
2
, and repeated angiography can be helpful monitors for the early detection of critical conditions after SVT. Local HbSO
2
has a greater sensitivity to predict outcome than lCBF. Moreover, therapies directed to improve perfusion pressure or reduce vascular resistance may open further therapeutic windows during SVT progression.