Abstracts of Literature
Prevalence of Symptomatic Intracranial Aneurysm and Ischemic Stroke in Pseudoxanthoma Elasticum— van den Berg JSP (Dept of Neurology, Univ Hospital Nijmegen, PO Box 9101 NL-6500 HB Nijmegen, Netherlands), Hennekam RCM, Cruysberg JRM, Steijlen PM, Swart J, Tijmes N, Limburg M—Cerebrovasc Dis. 2000;10:315–319. Copyright © 2000 S. Karger AG, Basel.
Background: Pseudoxanthoma elasticum (PXE) is an heritable connective tissue disorder with clinical manifestations of the ocular, dermal, and cardiovascular system. The purpose of this study was to investigate the prevalence of symptomatic intracranial aneurysms (IAs) and ischaemic stroke (IS) in PXE. Methods: The records of 100 patients with PXE were retrieved. All patients were contacted and data on complications were collected. The literature was reviewed regarding PXE, ISs, and IAs. Results: No patient with PXE had a symptomatic IA as presenting symptom. One patient presented with an IS. During follow-up of 94 of the 100 patients (mean follow-up 17.1 years, range 1–49 years), none presented a symptomatic IA (3,168 retrospective patient observation years and 1,602 prospective patient observation years). Upper gastrointestinal haemorrhage during follow-up occurred in 17 patients, in 1 patient during aspirin use. One patient has IS as presenting symptom and a recurrence during follow-up, and 7 patients had IS during follow-up. All were caused by small-vessel disease. The relative risk of IS in PXE under 65 years compared with the general population was 3.6 (95% confidence interval 3.3–4.0). Conclusions: On the basis of the currently available data, an association between symptomatic IAs and PXE is unlikely. However, the incidence of IS, due to small-vessel disease, was increased. Antiplatelet therapy in patients with PXE may lead to a high incidence of upper gastrointestinal haemorrhages.
Key Words: aneurysm, hereditary disease
Initial Hyperglycemia as an Indicator of Severity of the Ictus in Poor-Grade Patients With Spontaneous Subarachnoid Hemorrhage— Alberti O (Klinik für Neurochirurgie, Klinikum der Philipps-Universität, Baldingerstraße, 35043 Marburg, Germany), Becker R, Benes L, Wallenfang T, Bertalanffy H—Clin Neurol Neurosurg. 2000;102:78–83. Copyright © 2000 Elsevier Science B.V.
An association between hyperglycemia and outcome in spontaneous subarachnoid hemorrhage (SAH) has been sporadically reported. Our hypothesis was that hyperglycemia is a sign of central metabolic disturbance linked with specific appearances on computerized tomography (CT) scans reflecting different degrees of corresponding brain injury. The admission plasma glucose level, initial CT findings, and outcome after 6 months were analysed in a cohort of 99 patients with SAH in Hunt & Hess Grade IV or V. The CT scans were quantitatively assessed for subarachnoid blood, intracerebral hematoma, intraventricular hemorrhage, hydrocephalus, midline shift and compression of the perimesencephalic cisterns. These findings were combined to determine a three-point CT severity score. All patients showed elevated (>5.8 mmol/l) plasma glucose levels on admission. Mortality among 33 patients with glucose concentration below 9.0 mmol/l was 33.3%, 71.1% for the 45 patients with glucose level between 9.0 and 13.0 mmol/l, and 95.2% for the 21 patients with concentration above 13.0 mmol/l (P<0.0001). Glucose level was higher in Grade V than in Grade IV patients (mean±SD) (11.8±3.2 vs 9.8±2.9 mmol/l; P=0.0012). Patients with mild CT findings (n=10) had the lowest glucose level (8.9±1.8 mmol/l; P=0.0082), whereas patients with severe findings (n=56) had the highest glucose (11.4±3.5 mmol/l; P=0.011). Despite association with clinical grade and extent of CT findings, logistic multiple regression revealed the admission plasma glucose level to be an independent prognosticator of outcome. The prognostic potential of the initial plasma glucose level may be beneficial in management protocols of poor-grade SAH patients.
Key Words: subarachnoid hemorrhage , hyperglycemia
Small, Unruptured Intracranial Aneurysms and Management of Symptomatic Carotid Artery Stenosis—Kappelle LJ (Dept of Neurology, Univ Hospital Utrecht, H.p. nr. G03.228, Heidelberglaan 100, 3584 CX Utrecht, Netherlands), Eliasziw M, Fox AJ, Barnett HJM, for the North American Symptomatic Carotid Endarterectomy Trial Group—Neurology. 2000;55:307–309. Copyright © 2000 by AAN Enterprises, Inc.
Of the 2885 patients participating in the North American Symptomatic Carotid Endarterectomy Trial, 90 (3.1%) had unruptured intracranial aneurysms (UIA), of which 96% had a diameter of less than 10 mm. During an average 5-year follow-up, only one patient had subarachnoid hemorrhage 6 days after carotid endarterectomy (CE). For patients with unrepaired UIA, the 5-year stroke risk was 10% after CE and 22.7% with best medical care. Both risks are similar to those of patients without UIA. The decision regarding CE probably should not be influenced by the presence of a small UIA.
Key Words: aneurysm , carotid artery diseases
Decreased Nitric Oxide Availability Contributes to Acute Cerebral Ischemia After Subarachnoid Hemorrhage—Schwartz AY, Sehba FA (Dept of Neurosurgery, Box 1136, Mount Sinai School of Medicine, One Gustave L. Levy Place, New York, NY 10029), Bederson JB—Neurosurgery. 2000;47:208–215.
OBJECTIVE: Disturbances of the l-arginine-nitric oxide (NO) vasodilatory pathway have been implicated as a cause of acute vasoconstriction and ischemia after subarachnoid hemorrhage (SAH). Because NO-dependent vasodilatory mechanisms are still intact in this setting, acute vasoconstriction may be the result of limited NO availability after SAH. The present study examines this hypothesis by administration of the NO synthase inhibitor NG-nitro-l-arginine methyl ester (L-NAME).
METHODS: SAH was induced by the endovascular suture method in anesthetized rats. L-NAME (30 mg/kg intravenously) was injected 20 minutes before or 15, 30, or 60 minutes after SAH. Control rats received normal saline. Arterial and intracranial pressure and cerebral blood flow (CBF) were measured continuously for 60 minutes after SAH.
RESULTS: L-NAME administration 20 minutes before SAH produced a significant decrease in resting CBF (29.4±3.4%; P<0.05), but it had no effect on the acute decrease in CBF after SAH or on its early recovery up to 30 minutes after SAH. However, a significant decrease in CBF recovery was found in animals receiving L-NAME injections (28.7±9.4%; P<0.05 versus controls) 60 minutes after SAH. Administration of L-NAME 15 or 30 minutes after SAH had no effect on CBF recovery, as compared with controls. However, when administered 60 minutes after SAH, L-NAME decreased CBF significantly (45.4±8.8%; P<0.05 versus controls).
CONCLUSION: These results indicate a biphasic pattern of NO availability after SAH. NO-mediated vasodilation is limited during the first 30 minutes of SAH and is restored 60 minutes after SAH.
Key Words: subarachnoid hemorrhage , nitric oxide
Intracranial Aneurysms: Detection With Gadolinium-Enhanced Dynamic Three-Dimensional MR Angiography: Initial Results—Metens T (Dept of Radiology, Unité de RMN, Hôpital Erasme, Université Libre de Bruxelles, 808 route de Lennik, B-1070, Brussels, Belgium), Rio F, Balériaux D, Roger T, David P, Rodesch G—Radiology. 2000;216:39–46. Copyright © RSNA, 2000.
PURPOSE: To assess the clinical utility and accuracy of contrast material–enhanced dynamic three-dimensional (3D) T1-weighted magnetic resonance (MR) angiography in the detection of unruptured intracranial aneurysms.
MATERIALS AND METHODS: A prospective blinded comparison of 3D contrast-enhanced T1-weighted MR angiography with 3D inflow magnetization transfer and tilted optimized nonsaturating excitation (MT TONE) imaging, phase-contrast MR angiography, and conventional digital subtraction angiography (DSA) was performed in 32 consecutive patients. The first dynamic 3D contrast-enhanced T1-weighted acquisition was individually timed after injection of a bolus of gadolinium-based contrast agent to obtain an arterial phase image followed by two sequential venous phase images (three 18-second acquisitions). Two readers independently interpreted and graded the MR images for diagnostic confidence and depiction of aneurysms and subsequently compared them with DSA images.
RESULTS: Three-dimensional contrast-enhanced T1-weighted MR angiograms depicted all 23 aneurysms detected in 17 patients at DSA (mean size, 6 mm; range, 2–21 mm) with one false-positive result by one reader (sensitivity, 100%; specificity, 94%). MT TONE and phase-contrast images failed to depict one and seven aneurysms, respectively (MT TONE sensitivity of 96% and specificity of 100%, phase-contrast sensitivity of 70% and specificity of 100%). Aneurysm depiction at 3D contrast-enhanced T1-weighted MR angiography was significantly better than that at MT TONE imaging (P<.012), and that with both was significantly superior to that of phase-contrast imaging (P<.001). Differences in diagnostic confidence in the presence of an aneurysm were not significant between 3D contrast-enhanced T1-weighted and MT TONE imaging (P=.076).
CONCLUSION: Dynamic 3D contrast-enhanced T1-weighted MR angiography is a fast, efficient, and minimally invasive imaging method with which to diagnose intracranial aneurysms.
Key Words: aneurysm , angiography
Diffusion-Weighted Magnetic Resonance Imaging Identifies the “Clinically Relevant” Small-Penetrator Infarcts—Oliveria-Filho J (Harvard Univ, Massachusetts General Hospital School of Medicine, Dept of Neurology, Stroke Service, Blake 1291 B, 55 Fruit St, Boston, MA 02114), Ay H, Schaefer PW, Buonanno FS, Chang Y, Gonzalez RG, Koroshetz WJ—Arch Neurol. 2000;57:1009–1014.
BACKGROUND: Most patients initially seen with a clinical syndrome consistent with a small-penetrator infarct (SPI) also harbor multiple, chronic, hyperintense, white matter lesions on conventional magnetic resonance imaging (ie, T2-weighted image [T2WI] and fluid-attenuation inversion recovery [FLAIR] imaging). Diffusion-weighted imaging (DWI) can identify the clinically relevant “index infarction” in such circumstances, since it differentiates between acute and chronic lesions. OBJECTIVE: To determine the clinical and radiological predictors associated with misidentification of an SPI as acute using T2WI and FLAIR images in patients with an acute SPI seen on DWI. PATIENTS: Sixty-seven consecutive patients who had an SPI. METHODS: Two independent examiners, provided with brief clinical information, but blinded to DWI findings, sought a clinically appropriate lesion on T2WI and FLAIR imaging in 67 consecutive patients found to have an SPI seen on DWI. RESULTS: The index infarction based on evaluation of T2WI or FLAIR images was in a different location than the acute lesion as identified by DWI in 9 (13%) and 11 (16%) of 67 patients, respectively. Both T2WI and FLAIR imaging were rated normal in another 9% of the patients. Multivariate analysis showed that small lesion size (<10 mm) was the only predictor of misidentifying the clinically appropriate lesion on conventional magnetic resonance imaging (P<.01). CONCLUSIONS: T2-weighted imaging and FLAIR imaging fail to identify the clinically relevant SPI in almost one quarter of the patients found to have a lesion on DWI. The characteristics of DWI make it well suited for the detection of acute small infarcts. Diffusion-weighted imaging is necessary to consistently define the clinical-anatomical relations in patients initially seen with SPIs.
Key Words: lacunar infarction , magnetic resonance imaging
Management of Resistant Hypertension in Patients With Carotid Stenosis: High Prevalence of Renovascular Hypertension—Spence JD (Stroke Prevention and Atherosclerosis Research Centre, Siebens-Drake/Robarts Research Institute, 1400 Western Rd, London, Ont N6G 2V2, Canada)—Cerebrovasc Dis. 2000;10:249–254. Copyright © 2000 S. Karger AG, Basel.
Introduction: Patients with carotid stenosis are at high risk of vascular events and therefore require an optimal control of risk factors such as hypertension. As the treatment of hypertension differs according to the cause, we examined the prevalence of resistant hypertension, and the cause of hypertension, among patients with carotid stenosis followed closely in two randomized trials of carotid endarterectomy. Objective: The purpose of this study was to determine the prevalence of resistant hypertension and of secondary hypertension among patients with carotid stenosis. Methods: A chart review was performed of all patients from our center who participated in the North American Symptomatic Carotid Endarterectomy Trial or the Asymptomatic Carotid Artery Study to determine the prevalence of renovascular hypertension. Results: Among 170 patients with carotid stenosis followed in these two trials, 145 (83.5%) were hypertensive (systolic >160 or diastolic >90 mm Hg); at least 24 (14.1% overall, 16.6% of hypertensives) had renovascular hypertension based on either nuclear medicine renography, renal angiography or both; among the 79 patients with resistant hypertension (mean arterial pressure >130 mm Hg despite treatment), 20 (25.3%) had renovascular hypertension. Adrenocortical hyperplasia was the underlying cause of hypertension in 12 (7.1% of cases, 8.3% of hypertensives, 8.8% of resistant hypertensives). Blood pressures were significantly higher for patients with renovascular and adrenocortical hypertension (P<0.0001 for systolic, P=0.024 for diastolic pressures). Conclusion: Among patients with carotid stenosis, renovascular hypertension is unusually common. Resistant hypertension among such patients should lead to investigation and management directed at the cause of hypertension. Appropriate investigations might include plasma renin/aldosterone ratio, captopril renography and MRA of the renal arteries or renal angiography.
Key Words: carotid artery diseases , hypertension
Ischemic Stroke in Young Women: Risk of Recurrence During Subsequent Pregnancies—Lamy C, Hamon JB, Coste J, Mas JL (Service de Neurologie, Hôpital Sainte-Anne, 1 rue Cabanis, 75674 Paris Cedex 14, France) for the French Study Group on Stroke in Pregnancy—Neurology. 2000;55:269–274. Copyright © 2000 by AAN Enterprises, Inc.
Objective: To assess whether subsequent pregnancies increase the risk of recurrent stroke and whether the occurrence of an ischemic stroke affects reproductive history. Methods: The authors identified 489 consecutive women aged 15 to 40 years with a first-ever arterial ischemic stroke or cerebral venous thrombosis from the record system of nine French neurologic centers. Information on stroke recurrence and reproductive history was obtained by means of chart review, written questionnaire, and telephone interview. Results: Data were analyzed from 441 women (373 with arterial ischemic stroke and 68 with cerebral venous thrombosis). During a mean follow-up of 5 years, 13 arterial recurrent ischemic strokes occurred. There were no cases of recurrent cerebral venous thrombosis. The overall risk of recurrence was 1% within 1 year and 2.3% within 5 years. The risk of recurrence was significantly higher in patients with stroke of definite cause. Eleven recurrent strokes occurred outside pregnancy (absolute risk of recurrence=0.5%; 95% CI 0.3, 0.95) and two during pregnancy or the puerperium (absolute risk of recurrence=1.8%; 95% CI 0.5, 7.5). The relative risk of recurrence was significantly higher during the postpartum period (risk ratio=9.7; 95% CI 1.2, 78.9) than during pregnancy (risk ratio=2.2; 95% CI 0.3, 17.5) itself. The outcome of the 187 subsequent pregnancies was similar to that expected from the general population. Thirty-four percent of women indicated that they would have desired more pregnancies after their initial stroke. The main reasons for not considering pregnancy were concern of a recurrent stroke, medical advice against pregnancy, and residual handicap. Conclusion: Young women with a history of ischemic stroke have a low risk of recurrence during subsequent pregnancies. The postpartum period, not the pregnancy itself, is associated with an increased risk of recurrent stroke. The outcome of pregnancies in these women appears to be similar to that expected in the general population. A previous ischemic stroke is not a contraindication to a subsequent pregnancy.
Key Words: cerebral infarction , women
Common Carotid Intima-Media Thickness Predicts Occurrence of Carotid Atherosclerotic Plaques: Longitudinal Results From the Aging Vascular (EVA) Study—Zureik M (INSERM U 258, Hôpital Paul Brousse, 16 av. Paul Vaillant Couturier, 94807 Villejuif Cedex, France), Ducimetière P, Touboul P-J, Courbon D, Bonithon-Kopp C, Berr C, Magne C—Arterioscler Thromb Vasc Biol. 2000;20:1622–1629. Copyright © 2000 American Heart Association, Inc.
The role of the increase in the common carotid artery (CCA) intima-media wall thickness (IMT) in the atherosclerotic process is questionable. This longitudinal study examined the predictive value of CCA-IMT measured at baseline examination (at sites free of plaques) on the occurrence of atherosclerotic plaques in the extracranial carotid arteries during 4 years of follow-up study in a sample of 1010 subjects aged 59 to 71 years. Ultrasound examinations were performed at baseline and 2 years and 4 years later. The occurrence of carotid plaques during follow-up was defined as the appearance of ≥1 plaque in previously normal carotid segments and/or the appearance of new plaques in the carotid segments that previously had plaques. Carotid plaque occurrence was observed in 185 subjects (18.3%). Age- and sex-adjusted odds ratios of carotid plaque occurrence were 2.66 (95% CI 1.58 to 4.46, P<0.001) in subjects having intermediate baseline CCA-IMT values (quartiles 2 and 3) and 3.67 (CI 2.09 to 6.44, P<0.001) in those having the highest baseline CCA-IMT values (quartile 4) compared with those having the lowest baseline CCA-IMT values (quartile 1). Multivariate adjustment for major cardiovascular risk factors did not alter the results. These findings were observed for men and women as well as for subjects with and without carotid plaques at baseline. This 4-year longitudinal study shows that CCA-IMT predicts carotid plaque occurrence in a large sample of relatively old subjects. It extends the findings obtained from cross-sectional studies and suggests that increased intima-media thickness might occur in an earlier phase of the atherosclerotic process.
Key Words: carotid artery diseases , atherosclerosis
Role of a Stroke Data Bank in Evaluating Cerebral Infarction Subtypes: Patterns and Outcome of 1,776 Consecutive Patients From the Besançon Stroke Registry—Moulin T (Service de Neurologie, CHU Jean Minjoz, F-25030 Besançon, France), Tatu L, Vuillier F, Berger E, Chavot D, Rumbach L—Cerebrovasc Dis. 2000;10:261–271. Copyright © 2000 S. Karger AG, Basel.
The purpose of this study was to estimate the frequency of various risk factors, courses and outcome of infarct subtypes in a large hospital-based stroke registry. Methods: From 1987 to 1994, 1,776 stroke patients with a first-ever infarction were included in the Besançon Stroke Registry. All patients were evaluated by a standard protocol (risk factors, stroke onset, stroke courses, clinical characteristics, neuroimaging, Doppler ultrasonography and cardiac investigations). Outcome was evaluated at 30 days using the Rankin scale. Results: There were 1,012 men (mean age 67.2±13.7 years) and 764 women (mean age 71.4±15.6 years). At least two neuroimaging examinations were performed in 81.4% (n=1,446) of the patients and an infarct was visible in 80.9% (n=1,436). The second neuroimaging examination (CT or MRI) was performed after 8.2±1.6 days. 85.4% of patients were admitted on the first day of the stroke: 28.3% within 3 h and 48.4% within 6 h. In addition, stroke severity was well correlated with the short time interval between stroke onset and admission. Past medical history of hypertension was the major risk factor occurring in 57.5% of all types of infarction. While diabetes was more frequently found in small deep infarct, atrial fibrillation and history of heart failure were found in anterior circulation infarcts. The distribution of clinical presentations was conventional. Hemorrhagic transformation was found in 14.9% of the patients, especially in MCA and PCA infarcts. In all patients, logistic regression analysis determined independent predictive factors for death: clinical deterioration at the 48th hour (OR 7.5, 95% CI 4.9–11.3), initial loss of consciousness (OR 3.3, 95% CI 2.1–4.9), age (OR 1.05, 95% CI 1.03–1.06), complete motor deficit (OR 2.6, 95% CI 1.7–3.8), history of heart failure (OR 1.9, 95% CI 1.3–3.0), lacunar syndrome (OR 0.25, 95% CI 0.10–0.60) and regressive stroke onset (OR 0.24, 95% CI 0.10–0.52). However, the outcome was clearly correlated with the infarct location. The in-hospital mortality rate was lowest in patients with small deep infarct (2.9%) or border zone infarcts (3.4%) and the highest in patients with total middle cerebral artery infarct (47.4%) or multiple infarcts (27.6%). Conclusion: Our registry appears to be a useful tool to understand the course and outcome of a large group of nonselected patients with subtypes of infarction. It can also help to analyze the influence of specific stroke management in the different categories of stroke types.
Key Words: cerebral infarction , stroke outcome
Carotid Atherosclerosis, Vascular Risk Profile and Mortality in a Population-Based Sample of Functionally Healthy Elderly Subjects: The Berlin Ageing Study—Hillen T (King’s College London, Dept of Public Health Sciences, 5th Floor, Capital House, London SE1 8QD, UK), Nieczaj R, Münzberg H, Schaub R, Borchelt M, Steinhagen-Thiessen E—J Intern Med. 2000;247:679–688.
Objectives. Studies on extracranial carotid atherosclerosis have predominately been undertaken on middle-aged subjects. This study examines the prevalence of extracranial carotid atherosclerosis, its relation to vascular risk factors and its significance for survival in elderly subjects.
Design. Population-based cross-sectional survey. Non-modifiable vascular risk factors examined were family history of atherosclerotic disease, sex and apolipoprotein E (apoE) genotype. Potentially modifiable risk factors assessed were smoking, fibrinogen, fasting lipids, body mass index, hypertension and diabetes.
Setting and subjects. Two hundred and twenty-five functionally healthy volunteers of the Berlin Ageing Study, aged 70–100.
Main outcome measures. Presence of carotid stenosis and plaque ascertained by ultrasound imaging: 5-year mortality.
Results. At least one plaque was found in 144 (64%) of the volunteers: 34 (15%) had a stenosis over 50%: and nine (4%) had a stenosis over 75%. Total cholesterol >6.5 mmol L−1. LDL cholesterol >4.6 mmol L−1 and total cholesterol/HDL cholesterol ratio >5 were significantly associated with presence of plaque in 70- to 80-year-old subjects, as was diabetes in subjects over 80 years. Log-linear analyses showed significant three-way interactions for high LDL cholesterol and diabetes with plaques and age. Family history, sex, apoE genotype, smoking and fibrinogen were not related to presence of plaque in the study population. Cox regression analysis revealed increased 5-year mortality rates for subjects with plaques (OR=2.88; 95% CI=1.30–6.35), whereas the vascular risk profile was not associated with mortality.
Conclusions. In a population-based sample of functionally healthy elderly subjects, the significance of the vascular risk profile seemed to be diminished. It had no impact on survival and only modifiable risk factors showed an age-dependent association with carotid disease.
Key Words: carotid artery diseases , atherosclerosis
A Metabolic Threshold of Irreversible Ischemia Demonstrated by PET in a Middle Cerebral Artery Occlusion-Reperfusion Primate Model—Frykholm P, Andersson JLR, Valtysson J, Silander HC, Hillered L, Persson L, Olsson Y, Yu WR, Westerberg G, Watanabe Y, Långström B, Enblad P (Dept of Clinical Neurosciences, Section of Neurosurgery, Univ Hospital, S-751 85 Uppsala, Sweden)—Acta Neurol Scand. 2000;102:18–26. Copyright © Munksgaard 2000.
Objective—To evaluate the predictive value of measurements of regional cerebral blood flow (CBF), oxygen metabolism (CMRO2) and oxygen extraction ratio (OER) for assessment of the fate of ischemic brain tissue. Materials and methods—Sequential PET measurements were performed during middle cerebral artery occlusion (MCAO; 2 h) and 12–24 h (mean 18 h) of reperfusion in a primate model (Macaca mulatta, n=8). A penumbra region was delineated on the MCAO PET image (OER >125% and CMRO2 ≥45% of the values observed in the contralateral hemisphere, respectively) and an infarction region was delineated on the last PET image (CMRO2 <45% of the values observed in the contralateral hemisphere). The penumbra regions delineated during MCAO and the infarction regions delineated at the final PET, were copied on to the images from all other PET sessions for measurements of CBF, CMRO2 and OER. Ratios were calculated by dividing the mean values obtained by the values of the corresponding contralateral region. Results—Histopathology verified the adequacy of the criteria applied in the last PET for delineation of the infarction region. The penumbra region and infarction region were separated in all cases, except in two cases where a minimal overlap was seen. CBF and OER showed considerable variation over time and there was no consistent difference between the penumbra and infarction regions. CMRO2 showed a more stable pattern and the difference between penumbra and infarction regions was maintained from the time of MCAO throughout the entire reperfusion phase. With CMRO2 as predictor, all 50 observations could be correctly predicted as penumbra or infarction when using an optimal threshold ratio value estimated to be in the interval of 61% to 69% of the corresponding contralateral region. CBF and OER proved to have low power as predictors. Conclusions—The results indicate that CMRO2 is the best predictor of reversible or irreversible brain damage and the critical metabolic threshold level appears to be a reduction of oxygen metabolism to between 61% and 69% of the corresponding contralateral region.
Key Words: cerebral blood flow , cerebral ischemia
High Susceptibility to Cerebral Ischemia in GFAP-Null Mice—Nawashiro H (Dept of Neurosurgery, National Defense Medical College, 3-2 Namiki, Tokorozawa, Saitama, 359-8513, Japan), Brenner M, Fukui S, Shima K, Hallenbeck JM—J Cereb Blood Flow Metab. 2000;20:1040–1044. Copyright © 2000 The International Society for Cerebral Blood Flow and Metabolism.
Astrocytes perform a variety of functions in the adult central nervous system (CNS) that contribute to the survival of neurons. Thus, it is likely that the activities of astrocytes affect the extent of brain damage after ischemic stroke. The authors tested this hypothesis by using a mouse ischemia model to compare the infarct volume produced in wild-type mice with that produced in mice lacking glial fibrillary acidic protein (GFAP), an astrocyte specific intermediate filament component. Astrocytes lacking GFAP have been shown to have defects in process formation, induction of the blood–brain barrier, and volume regulation; therefore, they might be compromised in their ability to protect the CNS after injury. The authors reported here that 48 hours after combined permanent middle cerebral artery occlusion (MCAO) and 15 minutes transient carotid artery occlusion (CAO) GFAP-null mice had a significantly (P<0.001) larger cortical infarct volume (16.7±2.2 mm3) than their wild-type littermates (10.1±3.9 mm3). Laser-Doppler flowmetry revealed that the GFAP-null mice had a more extensive and profound decrease in cortical cerebral blood flow within 2 minutes after MCAO with CAO. These results indicated a high susceptibility to cerebral ischemia in GFAP-null mice and suggested an important role for astrocytes and GFAP in the progress of ischemic brain damage after focal cerebral ischemia with partial reperfusion.
Key Words: cerebral ischemia , astrocytes
Complement Activation in the Brain After Experimental Intracerebral Hemorrhage—Hua Y, Xi G (Univ of Michigan, Dept of Surgery/Neurosurgery, R5550 Kresge 1, Ann Arbor, MI 48109), Keep RF, Hoff JT—J Neurosurg. 2000;92:1016–1022.
OBJECT: Brain edema formation following intracerebral hemorrhage (ICH) appears to be partly related to erythrocyte lysis and hemoglobin release. Erythrocyte lysis may be mediated by the complement cascade, which then triggers parenchymal injury. In this study the authors examine whether the complement cascade is activated after ICH and whether inhibition of complement attenuates brain edema around the hematoma. METHODS: This study was divided into three parts. In the first part, 100 microl of autologous blood was infused into the rats’ right basal ganglia, and the animals were killed at 24 and 72 hours after intracerebral infusion. Their brains were tested for complement factors C9, C3d, and clusterin (a naturally occurring complement inhibitor) by using immunohistochemical analysis. In the second part of the study, the rats were killed at 24 or 72 hours after injection of 100 microl of blood. The C9 and clusterin proteins were quantitated using Western blot analysis. In the third part, the rats received either 100 microl of blood or 100 microl of blood plus 10 microg of N-acetylheparin (a complement activation inhibitor). Then they were killed 24 or 72 hours later for measurement of brain water and ion contents. It was demonstrated on Western blot analysis that there had been a sixfold increase in C9 around the hematoma 24 hours after the infusion of 100 microl of autologous blood. Marked perihematomal C9 immunoreactivity was detected at 72 hours. Clusterin also increased after ICH and was expressed in neurons 72 hours later. The addition of N-acetylheparin significantly reduced brain edema formation in the ipsilateral basal ganglia at 24 hours (78.5±0.5% compared with 81.6±0.8% in control animals, P<0.001) and at 72 hours (80.9±2.2% compared with 83.6±0.9% in control animals, P<0.05) after ICH. CONCLUSIONS: It was found that ICH causes complement activation in the brain. Activation of complement and the formation of membrane attack complex contributes to brain edema formation after ICH. Blocking the complement cascade could be an important step in the therapy for ICH.
Key Words: intracerebral hemorrhage , brain edema
CT Angiography for the Detection of Cerebral Vasospasm in Patients With Acute Subarachnoid Hemorrhage—Anderson GB (Div of Neurosurgery, Univ of Alberta, 2D1 WMC, 8440-112 St, Edmonton, Alberta, Canada T6G 2B7), Ashforth R, Steinke DE, Findlay JM—AJNR. 2000;21:1011–1015. Copyright © American Society of Neuroradiology.
BACKGROUND AND PURPOSE: Digital subtraction angiography (DSA) is the standard of reference for detecting cerebral vasospasm after subarachnoid hemorrhage (SAH). CT angiography (CTA) is a relatively recent method for depicting the intracranial arterial vasculature. The purpose of this study was to compare CTA and DSA in the detection and quantification of cerebral vasospasm.
METHODS: Seventeen patients with SAH underwent initial CTA with or without DSA and follow-up CTA and DSA. The follow-up CTA and DSA studies were performed within 24 hours of each other and 5 to 10 days after SAH. Maximum intensity projection images were produced for each CTA. Six arterial locations were examined for spasm: the suprasellar internal carotid artery (ICA), the M1 and M2 segments of the middle cerebral artery, the A1 and A2 segments of the anterior cerebral artery, and the basilar artery. Vasospasm was categorized as none, mild (<30% luminal reduction), moderate (30% to 50% reduction), or severe (>50% reduction).
RESULTS: The overall correlation between CTA and DSA was 0.757, but was better for proximal than distal locations (0.88–1.00 versus 0.152–0.446). Agreement between CTA and DSA was greater for no spasm (92%) and severe spasm (100%) than for mild (57%) or moderate (64%) spasm. CTA was highly accurate for no spasm or severe spasm in proximal locations (96%, and 100%, respectively); it was less accurate (90% and 95%, respectively) for mild or moderate spasm in these locations. For distal locations, the accuracy for absent, mild, moderate, or severe spasm was 78%, 81%, 94%, and 100%, respectively.
CONCLUSION: CTA is highly sensitive, specific, and accurate in detecting no spasm or severe cerebral vasospasm in proximal arterial locations; it is less accurate for detecting mild and moderate spasm in distal locations.
Key Words: subarachnoid hemorrhage , angiography
What Is the Significance of Leukoaraiosis in Patients With Acute Ischemic Stroke? Wiszniewska M, Devuyst G (Dept of Neurology, CHUV [BH 07] rue du Bugnon 46, 1011 Lausanne, Switzerland), Bogousslavsky J, Ghika J, van Melle G—Arch Neurol. 2000;57:967–973.
Background: Leukoaraiosis (LA) may have specific clinical correlates in patients with stroke, but this is not well investigated, so that the significance of LA in patients with stroke remains unclear.
Methods: In a study of 2289 patients with a first-ever acute ischemic stroke, LA was noted in 149 by the use of baseline computed tomography of the brain. These patients were compared with the non-LA group. Statistical tests, including Fisher exact test or a χ2 test, were used to compare variables, and a multivariate approach using stepwise logistic regression was performed.
Results: Patients with LA were significantly older (73.7 vs 62.7 years; P<.001), and had a higher incidence of hypertension (72.5% vs 47.1%; P<.001) and subcortical or lacunar infarction (40.3% vs 25.4% and 21.5% vs 8.0%, respectively; P<.001) on neuroimaging studies, compared with the non-LA group. The most common cause of stroke in the LA group was presumed to be small-artery disease associated with hypertension (46% vs 13.5% in the non-LA group). Age and hypertension were very strongly associated with LA (respective odds ratios [95% confidence intervals], 1.06 [1.04–1.08] and 2.33 [1.60–3.39]). In addition to these risk factors, a close relationship was found between LA and nonsevere stenosis (<50%) of the internal carotid artery (odds ratio, 2.23 [95% confidence interval, 1.32–3.76]), although the significance of this association remains speculative. The outcome at 1 month after stroke was similar in both groups.
Conclusion: Our results provide further evidence that LA is related primarily to small-vessel disease.
Key Words: cerebral infarction , leukoaraiosis
A Comparison of Cerebral Hemodynamic Parameters Between Transient Monocular Blindness Patients, Transient Ischemic Attack Patients and Control Subjects—Rutgers DR (Dept of Radiology, E01.132 Univ Medical Center, Heidelberglaan 100 NL-3584 CX Utrecht, Netherlands), Donders RCJM, Vriens EM, Kappelle LJ, van der Grond J—Cerebrovasc Dis. 2000;10:307–314. Copyright © 2000 S. Karger AG, Basel.
Purpose: To assess whether patients with transient monocular blindness (TMB) and patients with hemispheric transient ischemic attacks (hTIA) differ from each other with respect to cerebral hemodynamic parameters. Methods: Seventeen TMB patients and 23 hTIA patients with a moderate to severe stenosis or an occlusion of the internal carotid artery (ICA) underwent magnetic resonance (MR) angiography, 1H MR spectroscopy and transcranial Doppler sonography. Thirty-one control subjects were investigated to obtain reference values for the MR investigations. Quantitative flow was measured in the ICAs, the basilar artery and the middle cerebral arteries (MCA). Metabolic changes in the MCA territory were studied by assessing N-acetyl-aspartate (NAA/choline ratios and prevalences of lactate. The prevalence of collateral flow was assessed in the circle of Willis and the ophthalmic arteries. The vasomotor reactivity was studied by measuring the CO2 reactivity of the MCA territories. Results: Quantitative flow in the cerebropetal arteries and the MCAs did not differ between TMB patients and hTIA patients. Also patterns of collateral flow, prevalence of lactate and CO2 reactivity were similar. The mean ipsilateral NAA/choline ratio was lower in hTIA patients compared with TMB patients (p<0.01), and was predominantly correlated with symptomatology (p<0.01), i.e. whether patients had TMB or hTIA, and not with ipsilateral MCA flow (p=0.2) or ipsilateral CO2 reactivity (p=0.7). Conclusion: The results of this study indicate that there are no cerebral hemodynamic differences between TMB patients and hTIA patients. It is therefore unlikely that hemodynamic factors account for differences in clinical characteristics between the two patient groups.
Key Words: vasomotor reactivity , cerebral ischemia, transient
Cerebral Blood Flow in Nondemented Elderly Subjects With Extensive Deep White Matter Lesions on Magnetic Resonance Imaging—Yao H (Second Dept of Internal Medicine, Faculty of Medicine, Kyushu Univ, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan), Yuzuriha T, Fukuda K, Matsumoto T, Ibayashi S, Uchimura H, Fujishima M—J Stroke Cerebrovasc Dis. 2000;9:172–175.
Our previous study showed that deep white matter lesions (DWML) were associated with subtle cognitive decline in community-dwelling elderly people. However, even extensive (EXT)-DWML, found in 7 (4%) of 178 subjects aged 60 years or older, did not cause dementia. The purpose of the present study was to investigate brain circulation in nondemented elderly subjects with EXT-DWML. We compared cerebral blood flow in the deep white matter and frontal cortex between 5 subjects with EXT-DWML and 5 without such lesions, using a xenon-enhanced computed tomography (CT) method. Although the difference of deep white matter findings on magnetic resonance imaging (MRI) was the greatest possible (i.e., extensive v no or minimum lesions), cerebral blood flow values in anterior deep white matter and frontal cortex were 21.4±5.3 standard deviation (SD) mL/100 g/minute and 42.7±4.1, respectively, in subjects with extensive lesions, which were not significantly different from 24.3±4.3 and 44.0±7.1 in subjects without DWML. The present study suggests that EXT-DWML in nondemented elderly individuals do not necessarily indicate apparent hypoperfusion or marked cognitive decline.
Key Words: cerebral blood flow , aging
Microembolic Signal Monitoring in Hemispheric Acute Ischaemic Stroke: A Prospective Study—Serena J (Sec of Neurology, Hospital Universitari Doctor Josep Trueta, E-17007 Girona, Spain), Segura T, Castellanos M, Dávalos A—Cerebrovac Dis. 2000;10:278–282. Copyright © 2000 S. Karger AG, Basel.
Background and Purpose: There are few data on the occurrence of microembolic signals (MES) in the acute phase of ischaemic stroke. The objective of our work was to systematically study the frequency of MES in nonselected patients with a first-ever hemispheric transient ischemic attack (TIA) or acute cerebral infarction, and to evaluate the clinical usefulness of MES detection. Methods: 182 consecutive patients with hemispheric TIA or acute cerebral infarction, and 54-age-matched healthy controls were studied. Bilateral transcranial Doppler ultrasound (TCD) monitoring was performed for at least 30 min with a mean time from stroke onset to TCD of 69 h. Stroke severity on admission, early recurrent stroke and dependency on discharge were investigated. Results: MES were detected in 20.5% of patients with arterial sources of embolism, 17.1% of patients with potential sources of cardioembolism and 5% of patients with cryptogenic stroke. They were not registered, however, in lacunar infarctions (p<0.001). Stroke severity on admission of patients with MES was greater than that of patients without MES (47.1 vs. 19.4% with the Canadian Stroke Scale ≤6.5; p=0.009). Early recurrent stroke was more frequent in patients with MES (11.8%) than in those without MES (4.2%) although the difference was not statistically significant. Multiple logistic regression analysis showed that MES increased the risk of dependency on discharge (odds ratio, 4.2; 95% CI, 1.2–14.9; p=0.01) independently of age, stroke severity on admission and presence of an arterial or cardiac embolic source. Conclusions: There is a strong association of MES in the acute phase of stroke with known potential arterial and cardiac embolic sources. MES have an independent predictive value of poor outcome.
Key Words: stroke, acute , cerebral embolism
Middle Cerebral Artery Blood Flow Velocity in Elite Power Athletes During Maximal Weight-Lifting—Dickerman RD (National Institutes of Health, Surgical Neurology Branch, 10 Center Dr, Bldg 10, Rm 5D37, Bethesda, MD 20892), McConathy WJ, Smith GH, East JW, Rudder L—Neurol Res. 2000;22:337–340. Copyright © 2000 Forefront Publishing Group.
Cerebral blood flow velocity (CBFV) has been shown to significantly increase during dynamic exercise (running) secondary to increases in cardiac output. Static exercise (weight-lifting) induces supraphysiological arterial pressures up to 450/380 mmHg, and thus may alter CBFV. Catastrophic brain injuries such as stroke, cerebral hemorrhage, subarachnoid hemorrhage, retinal hemorrhage and retinal detachment have been associated with weight-lifting. A recent study has shown that intra-ocular pressure (IOP), which is an indirect measure of intracranial pressure, elevates to pathophysiologic levels during weight-lifting. Recent CBFV studies instituting Valsalva have demonstrated decreases in CBFV from 21%–52%. To date, no studies have examined CBFV during maximal weight-lifting to elucidate the cerebrovascular responses to extreme pressure alterations. We recruited nine elite power athletes, including a multi-world record holder in powerlifting, for a transcranial Doppler study of middle cerebral artery blood flow velocity at rest and during maximal weight-lifting. All subjects’ resting blood flow velocities were within normal ranges (mean 64.4±9.5 cm sec2). Blood flow velocities were significantly (P<0.0001) decreased in all subjects during maximal lifting (mean 48.4±10.1 cm sec2). Linear regression analysis demonstrated a significant inverse linear relationship in the net change of blood velocities from rest to maximal lift for each subject (r=0.8585, P<0.001). This study demonstrates that blood flow velocities are significantly decreased during heavy resistance training. The drop in CBFV during weight-lifting was significantly less than previous Valsalva studies, which likely reveals the cardiovascular, baroreflex, and cerebrovascular system adaptations occurring in these elite power athletes.
Key Words: cerebral blood flow , exercise
Correlation of Cerebral Hemodynamic Changes During Mental Activity and Recovery After Stroke—Bragoni M, Caltagirone C, Troisi E, Matteis M, Vernieri F, Silvestrini M (Clinica Neurologica, Università di Roma “Tor Vergata,” Ospedale S. Eugenio, P.le dell’Umanesimo 10, 00144 Rome, Italy)—Neurology. 2000;55:35–40. Copyright © 2000 by AAN Enterprises, Inc.
Objective: To investigate the correlation between changes in cerebral functional activity during mental engagement and the potential for neurologic recovery after stroke. Background: Transcranial Doppler ultrasonography (TCD) makes it possible to detect the dynamic adjustment of cerebral perfusion related to functional neuronal changes. Methods: TCD monitoring of flow velocity changes in the middle cerebral artery of 29 ischemic stroke patients was performed during an object recognition task. The study took place within 4 weeks from stroke onset. Based on recovery occurring after 2 months, the patients were divided into four groups depending on the side of hemispheric lesion and the presence or absence of neurologic recovery. Ten healthy subjects served as control subjects. Results: During the recognition task, control subjects showed a bilateral increase in flow velocity with respect to the rest phase (right side, 7.02±1.3%; left side, 6.65±1.1%), with no side-to-side difference. In patients who experienced recovery, a similar pattern of bilateral activation was observed, irrespective of the side of the lesion. Conversely, in patients with no recovery, the increase of flow velocity was significantly higher on the side contralateral to the brain lesion (p<0.0001) with respect to the lesion side. Performance during the recognition task was comparable in the four groups of patients. Conclusions: These findings suggest that satisfactory recovery from a neurologic deficit requires the persistence of functional activity in the damaged hemisphere despite the presence of an anatomic lesion. The possibility of obtaining early prognostic indications with TCD may be relevant for an early selection of patients with the best probability of benefiting from rehabilitation therapy.
Key Words: stroke outcome , cerebral blood flow
Effect of Treating Isolated Systolic Hypertension on the Risk of Developing Various Types and Subtypes of Stroke: The Systolic Hypertension in the Elderly Program (SHEP)—Perry Jr HM (Washington Univ, Box 8048, 660 S Euclid Ave, St Louis, MO 63110), Davis BR, Price TR, Applegate WB, Fields WS, Guralnik JM, Kuller L, Pressel S, Stamler J, Probstfield JL, for the Systolic Hypertension in the Elderly Program (SHEP) Cooperative Research Group—JAMA. 2000;284:465–471.
Context The Systolic Hypertension in the Elderly Program (SHEP) demonstrated that treating isolated systolic hypertension in older patients decreased incidence of total stroke, but whether all types of stroke were reduced was not evaluated.
Objective To investigate antihypertensive drug treatment effects on incidence of stroke by type and subtype, timing of strokes, case-fatality rates, stroke residual effects, and relationship of attained systolic blood pressure to stroke incidence.
Design The SHEP study, a randomized, double-blind, placebo-controlled trial began March 1, 1985, and had an average follow-up of 4.5 years.
Setting and Participants A total of 4736 men and women aged 60 years or older with isolated systolic hypertension at 16 clinical centers in the United States.
Interventions Patients were randomly assigned to receive treatment with 12.5 mg/d of chlorthalidone (step 1); either 25 mg/d of atenolol or 0.05 mg/d of reserpine (step 2) could be added (n=2365); or placebo (n=2371).
Main Outcome Measures Occurrence, type and subtype, and timing of first strokes and stroke fatalities; and change in stroke incidence for participants (whether in active treatment or placebo groups) reaching study-specific systolic blood pressure goal (decrease of at least 20 mm Hg from baseline to below 160 mm Hg) compared with participants not reaching goal.
Results A total of 85 and 132 participants in the active treatment and placebo groups, respectively, had ischemic strokes (adjusted relative risk [RR], 0.63; 95% confidence interval [CI], 0.48–0.82); 9 and 19 had hemorrhagic strokes (adjusted RR, 0.46; 95% CI, 0.21–1.02); and 9 and 8 had strokes of unknown type (adjusted RR, 1.05; 95% CI, 0.40–2.73), respectively. Four subtypes of ischemic stroke were observed in active treatment and placebo group participants, respectively, as follows: for lacunar, n=23 and n=43 (adjusted RR, 0.53; 95% CI, 0.32–0.88); for embolic, n=9 and n=16 (adjusted RR, 0.56; 95% CI, 0.25–1.27); for atherosclerotic, n=13 and n=13 (adjusted RR, 0.99; 95% CI, 0.46–2.15); and for unknown subtype, n=40 and n=60 (adjusted RR, 0.64; 95% CI, 0.43–0.96). Treatment effect was observed within 1 year for hemorrhagic strokes but was not seen until the second year for ischemic strokes. Stroke incidence significantly decreased in participants attaining study-specific systolic blood pressure goals.
Conclusions In this study, antihypertensive drug treatment reduced the incidence of both hemorrhagic and ischemic (including lacunar) strokes. Reduction in stroke incidence occurred when specific systolic blood pressure goals were attained.
Key Words: stroke prevention , hypertension
Cilostazol Stroke Prevention Study: A Placebo-Controlled Double-Blind Trial for Secondary Prevention of Cerebral Infarction—Gotoh F (35 Shinano-machi, Shinjuku-ku, Tokyo, Japan), Tohgi H, Hirai S, Terashi A, Fukuuchi Y, Otomo E, Shinohara Y, Itoh E, Matsuda T, Sawada T, Yamaguchi T, Nishimaru K, Ohashi Y—J Stroke Cerebrovasc Dis. 2000;9:147–157. Copyright © 2000 by National Stroke Association.
Cilostazol, an antiplatelet drug that increases the cyclic adenosine monophosphate (AMP) levels in platelets via inhibition of cyclic AMP phosphodiesterase, has been used in chronic arterial occlusive disease. The purpose of the present study was to examine the effects of cilostazol on the recurrence of cerebral infarction using a multicenter, randomized, placebo-controlled, double-blind clinical trial method. Patients who suffered from cerebral infarction at 1 to 6 months before the trial were enrolled between April 1992 and March 1996. Oral administration of cilostazol (100 mg twice daily) or placebo was randomly assigned to the patients and continued until February 1997. The primary endpoint was the recurrence of cerebral infarction. In total, 1,095 patients were enrolled. An analysis based on 1,052 eligible patients (526 given cilostazol and 526 given placebo) showed that the cilostazol treatment achieved a significant relative-risk reduction (41.7%; confidence interval [CI], 9.2% to 62.5%) in the recurrence of cerebral infarction as compared with the placebo treatment (P=.0150). Intention-to-treat analysis of 1,067 patients also showed a significant relative-risk reduction (42.3%; CI, 10.3% to 62.9%, P=.0127). No clinically significant adverse drug reactions of cilostazol were encountered. Long-term administration of cilostazol was effective and safe in the secondary prevention of cerebral infarction.
Key Words: stroke, acute , stroke management
Oral Anticoagulation Self-Management and Management by a Specialist Anticoagulation Clinic: A Randomised Cross-Over Comparison—Cromheecke ME, Levi M (Dept of Vascular Medicine/Internal Medicine, Academic Medical Centre F-4, Meibergdreef 9, 1105 AZ Amsterdam, Netherlands), Colly LP, de Mol BJM, Prins MH, Hutten BA, Mak R, Keyzers KCJ, Büller HR—Lancet. 2000;356:97–102.
Background Vitamin K antagonist treatment is effective for prevention and treatment of thromboembolic events but frequent laboratory control and dose-adjustment are essential. Small portable devices have enabled patient self-monitoring of anticoagulation and self-adjustment of the dose. We compared this self-management of oral anticoagulant therapy with conventional management by a specialist anticoagulation clinic in a randomised cross-over study.
Methods 50 patients on long-term oral anticoagulant treatment were included in a randomised controlled crossover study. Patients were self-managed or were managed by the anticoagulation clinic for a period of 3 months. After this period the alternative strategy was followed for each patient. Prothrombin time (expressed as international normalised ratio [INR]) were measured at intervals of 1–2 weeks in both periods without knowledge of type of management. The primary endpoint was the number of measurements within the therapeutic range (therapeutic target value ±50.5 INR units).
Findings There was no significant difference in the overall quality of control of anticoagulation between the two study periods. Patients were for 55% and for 49% of the treatment period within a range of ±0.5 from the therapeutic target INR during self-management and anticoagulation clinic management, respectively (p=0.06). The proportion of patients who spent most time in the therapeutic target range was larger during self-management than during anticoagulation clinic-guided management. The odds ratio for a better control of anticoagulation (defined as the period of time in the therapeutic target range) during self-management compared with anticoagulation clinic-guided management was 4.6 (95% CI 2.1–10.2). A patient-satisfaction assessment showed superiority of self-management over conventional care.
Interpretation Self-management of INR in the population in this study is feasible and appears to result in control of anticoagulation that is at least equivalent to management by a specialist anticoagulation clinic. It is also better appreciated by patients. Larger studies are required to assess the effect of this novel management strategy on the incidence of thromboembolic or bleeding complications.
Key Words: warfarin , anticoagulants
A Prospective Randomized Study on Bilateral Carotid Endarterectomy: Patching Versus Eversion—Ballotta E (Service of Vascular Surgery, Dept of Medical and Surgical Sciences, Univ of Padua, School of Medicine, Policlinico Universitario, Via N. Giustiniani, 2, 35128 Padova, Italy), Renon L, Da Giau G, Toniato A, Baracchini C, Abbruzzese E, Saladini M, Moscardo P—Ann Surg. 2000;232:119–125. Copyright © 2000 Lippincott Williams & Wilkins, Inc.
Objective To compare the clinical outcome and restenosis incidence of patients who underwent carotid endarterectomy with patch closure (CEAP) on one side and carotid eversion endarterectomy (CEE) on the other.
Summary Background Data Although a few investigators have compared the results of CEAP versus CEE, no reports have compared the outcome of CEAP versus CEE in the same patient.
Methods Eighty-six patients were randomly selected for sequential surgical treatment involving either CEAP/CEE or CEE/CEAP. All patients underwent postoperative duplex ultrasound study and clinical follow-up at 1, 6, and 12 months and every year thereafter. Various factors were analyzed to ascertain any association with restenosis, and Kaplan-Meier analysis was used to estimate the risk of restenosis.
Results Demographic and clinical data were similar in the CEAP and CEE groups. The selective shunting rate was statistically higher in the CEAP group. There were no perioperative deaths. Although the incidence of perioperative ipsilateral stroke was not significant, CEAP patients had a rate of combined transient ischemic attacks and strokes that approached statistical significance. The mean follow-up was 40 months. CEAP patients had a significantly higher incidence of restenosis and combined occlusive events and restenoses. Kaplan-Meier analysis showed that CEE had a significantly better cumulative patency rate than CEAP and that freedom from restenoses at 24 and 36 months was 87% and 83% for CEAP and 98% and 98% for CEE, respectively.
Conclusions CEE is less likely to cause perioperative neurologic complications and restenoses than CEAP. The significantly higher rate of unilateral recurrence suggests that local factors play a more important role than systemic factors in the occurrence of restenosis.
Key Words: carotid endarterectomy , surgical treatment
Gender and Carotid Endarterectomy: Does it Matter? Akbari CM (110 Francis St, Suite 5B, Boston, MA 02215), Pulling MC, Pomposelli FB Jr, Gibbons GW, Campbell DR, Logerfo FW—J Vasc Surg. 2000;31:1103–1108.
OBJECTIVE: Multiple large series have retrospectively identified female gender as a risk factor for perioperative stroke and death after carotid endarterectomy (CEA). METHODS: Data for all patients who underwent CEA at a single institution from January 1990 to December 1998 were entered into a computerized vascular registry and form the basis of this report. RESULTS: A total of 1298 CEA procedures were performed, of which 520 (40%) were in women and 778 (60%) in men. The mean age was 69.8±8.7 years for men and 71.2±8.5 years for women (P<.001). Cardiac risk factors significantly varied among the two groups, with women more likely to have diabetes (42% vs 36%) and hypertension (77% vs 66%), whereas tobacco history was higher among men (85% vs 71%) (P<.05 for all). Female patients were more likely to be asymptomatic at presentation (men, 44% vs women, 51%; P=.022). Postoperative myocardial infarction occurred in eight patients (0.6%) with no differences between men (0.4%) and women (1.0%) (P=not significant). For all adverse postoperative cardiac events (myocardial infarction, congestive heart failure, or arrhythmia), the incidence was 1.9% (25 patients), again with no differences between men (1.5%) and women (2.5%) (P=not significant). There were 25 postoperative neurologic events (19 strokes, six transient ischemic attacks) among the entire cohort (1.9%), of which 16 were in men (2.1%) and nine in women (1.6%; P=not significant). The overall postoperative stroke rate was 1.5% (13 [1.7%] of 778 men; 6 [1.2%;] of 520 women; P=not significant). Total operative mortality was 0.3% (3 [0.4%] of 778 men; 1 [0.2%] of 778 women; P=not significant). Late recurrent stenosis requiring operation developed in 14 patients (1.1%) during follow-up (6 [0.8%] of 778 men; 8 [1.5%] of 520 women; P=.19). CONCLUSIONS: Although there is significant variability in cardiac risk factors and presentation, female gender is not a risk factor for stroke, death, or cardiac morbidity after CEA. Women are not at higher risk for reoperation for recurrent stenosis.
Key Words: carotid endarterectomy , gender
Improving the Outcomes of Carotid Endarterectomy: Results of a Statewide Quality Improvement Project—Kresowik TF (UIHC Dept of Surgery, 200 Hawkins Dr, Iowa City, IA 52242), Hemann RA, Grund SL, Hendel ME, Brenton M, Wiblin RT, Adams HP, Ellerbeck EF—J Vasc Surg. 2000;31:918–926.
OBJECTIVE: The purpose of this study was to establish the statewide outcomes for carotid endarterectomy (CEA) and to facilitate improvement in outcomes through feedback, peer discussion, and ongoing process and outcome measurement. METHODS: The Medicare Part A claims files were used to identify all Medicare patients undergoing CEA in Iowa during two 12-month time periods (January 1994–December 1994 and June 1995–May 1996). Medical record abstraction was used to obtain surgical indications, perioperative care process, and outcome information. Confidential reports were provided to each hospital (N=30) where the procedure was performed. Surgeons performing the procedure (N=79) were invited to meetings to discuss care process variation and outcomes. Voluntary participation was solicited in a standardized program of ongoing hospital-based data collection of CEA process and outcome data. RESULTS: The statewide combined stroke or mortality rate decreased from 7.8% in 1994 to 4.0% in the 1995 to 1996 time period (P<.001). Fourteen hospitals, accounting for 74% of the statewide cases, participated in ongoing data collection. The combined stroke or mortality rate in these hospitals decreased significantly (P<.05) over time from 6.5% (1994) to 3.7% (1995–1996) to 1.8% (June 1997–May 1998). The use of intraoperative assessment of the operative site (20% in 1994, 46% in 1997–1998) and patch angioplasty (14% in 1994, 30% in 1997–1998) increased significantly during this time in the participating hospitals. CONCLUSIONS: Confidential feedback of outcome and process data for CEA may lead to change in perioperative care processes and improved outcomes. Standardized community-based outcome analysis should become routine for CEA to ensure that optimum results are being achieved.
Key Words: carotid endarterectomy , surgical treatment
Carotid Endarterectomy: Characterization of Recent Increases in Procedure Rates—Morasch MD (251 E Chicago Ave, Suite 628, Chicago, IL 60611), Parker MA, Feinglass J, Manheim LM, Pearce WH—J Vasc Surg. 2000;31:901–909.
INTRODUCTION: Recent increases in the rate of carotid endarterectomies (CEAs) have been attributed to results of clinical trials demonstrating efficacy when CEA is performed in centers of excellence. Subsequent population-based data suggest that trial results may not be matched in the community. This study was undertaken to characterize trends in CEA procedure rates after the dissemination of trial data and to describe any change in patient outcomes with population-based data from a single state. METHODS: Hospital administrative data on CEAs from 1992 to 1996 (n=45,744) were obtained for the state of Florida. Annualized CEA rates per 100,000 Florida residents were analyzed to determine trends in patient age, sex, admission type, size of hospital beds, ownership type and teaching status, and annual hospital and surgeon CEA volume. Outcomes were examined to track trends in complication rates. RESULTS: The annual number of CEA procedures increased 74% from 63.7 per 100,000 residents per year to 110.8 per 100,000 residents per year between 1992 and 1996. A single large increase occurred during the second half of 1994 when CEAs increased 73.5% from 16.6 per 100,000 residents per quarter to 28.8 per 100,000 residents per quarter after a clinical alert on benefits to CEAs in asymptomatic patients. Over 5 years, there were significant trends toward more nonemergent admissions, and more procedures were performed in high-volume hospitals and by high-volume surgeons. Procedure rates in both women and very elderly patients increased more than 70%, which was in step with younger patients and men. The incidence of inpatient stroke and death declined over the 5-year period, whereas the rate of perioperative myocardial infarction remained constant. CONCLUSIONS: Experience from Florida indicates that CEA rates increased as results of the Asymptomatic Carotid Artery Study disseminated. Trial results have been broadly interpreted to include women and very elderly patients. More patients are being referred to busier hospitals and to high-volume surgeons, which should continue to result in better patient outcomes.
Key Words: carotid endarterectomy , stroke management
Items of Interest
Ultrasound Contrast Enhancing Agents in Neurosonology: Principles, Methods, Future Possibilities—Droste DW (WWU Munster, Neurology Klin & Poliklin, Albert Schweitzer Str 33, D-48129 Munster, Germany), Kaps M, Navabi GD, Ringelstein EB—Acta Neurol Scand. 2000;102:1–10.
Primary Intracerebral Hemorrhages in the Besançon Stroke Registry—Tatu L (Service de Neurologie, CHU Jean—Minjoz, F-25030 Besançon, France), Moulin T, Mohamad RE, Vuillier F, Rumbach L, Czorny A—Eur Neurol. 2000;43:209–214. Copyright © 2000 S. Karger AG Basel.
Ischemic Stroke Risk With Oral Contraceptives: A Meta-Analysis—Gillum LA, Mamidipudi SK, Johnston SC (Dept of Neurology, Box 0114, Univ of California, San Francisco, 505 Parnassus Ave, San Francisco, CA 94143-0114)—JAMA. 2000;284:72–78.
Lipoprotein(a) and Stroke—Milionis HJ, Winder AF, Mikhailidis DP (Dept of Molecular Pathology and Clinical Biochemistry, Royal Free and Univ College Medical School, Univ College, Royal Free Campus, Pond St, London NW3 2QG, UK)—J Clin Pathol. 2000;53:487–496.
Ischemic Brain Metabolism in Patients With Chronic Cerebrovascular Disease: Increased Oxygen Extraction Fraction and Cerebrospinal Fluid Lactate—Ibayashi S (Second Dept of Internal Medicine, Faculty of Medicine, Kyushu Univ, Maidashi 3-1-1, Higashi-ku, Fukuoka, 812-8582 Japan), Irie K, Kitayama J, Nagao T, Kitazono T, Fujishima M—J Stroke Cerebrovasc Dis. 2000;9:166–171. Copyright © 2000 by National Stroke Association.
Depression After Stroke and Lesion Location: A Systematic Review—Carson AJ (Univ of Edinburgh, Royal Edinburgh Hospital, Dept of Psychiatry, Edinburgh EH10 5HF, Midlothian, Scotland), MacHale S, Allen K, Lawrie SM, Dennis M, House A, Sharpe M—Lancet. 2000;356:122–126.
Pravastatin Therapy and the Risk of Stroke—White HD (Cardiology Dept, Green Lane Hospital, Private Bag 92 189, Auckland 1030, New Zealand), Simes RJ, Anderson NE, Hankey GJ, Watson JDG, Hunt D, Colquhoun DM, Glasziou P, MacMahon S, Kirby AC, West MJ, Tonkin AM—N Engl J Med. 2000;343:317–326.
The abstracts in this section have been typeset for consistency with journal format but otherwise appear as in the original articles.
- Copyright © 2000 by American Heart Association