Abstracts of Literature
Cardiac Outcome in Patients With Subarachnoid Hemorrhage and Electrocardiographic Abnormalities—Zaroff JG (Cardiology Div, Univ of California, San Francisco, 505 Parassus Ave, San Francisco, CA 94143-0124), Rordorf GA, Newell JB, Ogilvy CS, Levinson JR—Neurosurgery. 1999;44:34–40.
OBJECTIVE: Approximately 25% of patients with subarachnoid hemorrhage (SAH) have electrocardiographic (ECG) abnormalities consistent with myocardial ischemia or myocardial infarction (MI), and their cardiac prognosis remains unclear. The objective of this study was to determine the cardiac and all-cause mortality rate of a series of patients with SAH with ECG changes consistent with ischemia or MI.
METHODS: Using an existing database of patients with SAH and predetermined ECG criteria for ischemia or MI, a study group of patients with abnormal ECG results within 3 days of presentation and before aneurysm surgery was identified. Database patients without abnormal ECG results served as a control group. Cardiac mortality, defined as death resulting from arrhythmia, congestive heart failure, or cardiogenic shock, was assessed by chart review.
RESULTS: Of 439 patients with SAH in the database, 58 met the criteria for the study group. Forty-one of these patients were treated neurosurgically. No deaths resulting from cardiac causes occurred, and 20 patients died as a result of noncardiac causes. In a multivariable analysis, age older than 65 years and Hunt and Hess grade of at least 3 were predictive of all-cause mortality. ECG abnormalities, however, were not a statistically significant predictor.
CONCLUSION: In patients with SAH and ECG readings consistent with ischemia or MI, the risk of death resulting from cardiac causes is low, with or without aneurysm surgery. The ECG abnormalities are associated with more severe neurological injury but are not independently predictive of all-cause mortality.
Key Words: subarachnoid hemorrhage, electrocardiography
Anticardiolipin Antibodies: A Study in Cerebral Venous Thrombosis—Christopher R (Dept of Neurochemistry, NIMHANS, Bangalore-560 029, India), Nagaraja D, Dixit NS, Narayanan CP—Acta Neurol Scand. 1999;99:121–124. Copyright ©Munksgaard 1999.
Objectives—Anticardiolipin antibodies (aCL) have been recognized as a marker for an increased risk of thrombosis. There are no documented reports from India on the prevalence of aCL in patients with cerebral venous thrombosis (CVT). Our study aimed at establishing the prevalence of these antibodies in patients with CVT and evaluating their clinical significance. Subjects and methods—Thirty-one patients with CVT diagnosed by angiography and/or cranial CT were investigated for the presence of aCL along with 31 age- and sex-matched normal controls. All subjects had no overt evidence of systemic lupus erythematosis or related autoimmune disorders. The titres of IgG and IgM type of aCL were estimated in the sera using a solid phase enzyme-linked immunosorbent assay. Results—Anticardiolipin antibodies were detected in 22.6% of CVT patients compared to 3.2% of normal controls (95% confidence interval (CI) 1.01 to 75.65). Five CVT patients had both IgG and IgM antibodies, and 2 had only IgG antibodies. The aCL positive group did not differ from the aCL-negative group with respect to the clinical characteristics and the demographic and risk factor profile. Conclusion—The findings suggest that anticardiolipin antibodies are a risk marker for cerebral venous thrombosis. Further studies on a larger group of patients are needed to establish the role of aCL in the pathogenesis of CVT.
Key Words: cerebral thrombosis, antibodies, anticardiolipin
Prospective Evaluation of the Angiotensin-Converting Enzyme Insertion/Deletion Polymorphism and the Risk of Stroke—Zee RYL (Cardiovascular Div, Thorn 1203, Brigham and Women’s Hospital, 75 Francis St, Boston, MA 02115), Ridker PM, Stampfer MJ, Hennekens CH, Lindpaintner K—Circulation. 1999;999:340–343. Copyright ©1999 American Heart Association, Inc.
Background—The D/I polymorphism of the ACE gene has been studied in relation to a variety of cardiovascular disorders, including stroke. A number of small studies have been conducted, with inconsistent results. We investigated the association between ACE genotype and the incidence of stroke in a large, prospective, matched case-control sample from the Physicians’ Health Study.
Methods and Results—In the Physicians’ Health Study, 348 subjects who had been apparently healthy at enrollment suffered a stroke during 12 years of follow-up, as determined from medical records and autopsy. A total of 348 cases were matched by age, time of randomization, and smoking habit to an equal number of controls (who had remained free of stroke). The D/I polymorphism was determined by polymerase chain reaction. Data were analyzed for the entire nested case-control sample, and also among a subgroup without a history of hypertension or diabetes mellitus, considered to be at low conventional risk (207 cases and 280 controls). All observed genotype frequencies were in Hardy-Weinberg equilibrium. The relative risk associated with the D allele was 1.11 (95% CI, 0.90 to 1.37; P=0.35), assuming an additive model in the matched analysis. Additional analyses assuming dominant or recessive effects of the D allele, as well as the analysis after stratification for low-risk status, showed no material as a statistically significant association.
Conclusions—The results of this large, prospective study indicate that the ACE D/I gene polymorphism is not associated with subsequent risk of stroke.
Key Words: angiotensins, risk factors
Carotid Intima-Media Thickness and Plaque in Patients With Familial Hypercholesterolaemia Mutations and Control Subjects—Tonstad S (Preventive Cardiology Clinic, Ullevål Hospital, N-0407 Oslo, Norway), Joakimsen O, Stensland-Bugge E, Ose L, Bønaa KH, Leren TP—Eur J Clin Invest. 1998;28:971–979. Copyright ©1998 Blackwell Science Ltd.
Background In individuals with familial hypercholesterolaemia (FH), ultrasonographic measurement of carotid intima–media thickness (IMT) and plaque may provide a non-invasive assessment of cardiovascular risk.
Methods We examined carotid artery IMT and its determinants in 79 non-smoking, normotensive, treated men and women with FH aged 26–46 years, and in 79 non-smoking, normotensive sex-, age- and body mass index-matched control subjects. FH was verified by molecular genetic analyses. The underlying mutation in the low-destiny lipoprotein receptor gene included a splice-site mutation, mutations predicted or shown to lead to class 2B mutations or other mutations that probably represent class I mutations (null alleles).
Results The carotid bifurcation and common carotid artery IMT was increased in men with FH compared with control subjects (0.81±0.15 mm vs. 0.74±0.19 mm and 0.61±0.13 mm vs. 0.55±0.14 mm respectively; P<0.05). The carotid bifurcation IMT was increased in women with FH compared with control subjects (0.74±0.17 vs. 0.66±0.15; P=0.005). More subjects with FH had carotid plaque (54% vs. 14%; P=0.0001). In multivariate analysis, male gender, level of low-density lipoprotein-cholesterol, cholesterol–years score and xanthoma were associated with IMT and plaque in subjects with FH. FH subjects with class 2B mutations had lower cholesterol levels than subjects with mutations belonging to the other classes. They also had a tendency towards a decreased common carotid artery IMT.
Conclusion These findings confirm the importance of gender, xanthoma and lifetime cholesterol levels in relation to carotid atherosclerosis in FH. Whether the type of mutation causing FH modulates carotid artery IMT and plaque requires further study.
Key Words: carotid artery diseases, hypercholesterolemia
Underutilization of Antithrombotic Therapy in Elderly Rural Patients With Atrial Fibrillation—Flaker GC (Univ Hospital and Clinics, One Hospital Dr, Columbia, MO 65212), McGowan DJ, Boechler M, Fortune G, Gage B—Am Heart J. 1999;137:307–312. Copyright ©1999 by Mosby, Inc.
Background Antithrombotic agents are underutilized in elderly patients with atrial fibrillation. In a peer-review audit of antithrombotic use in Missouri, rural patients were given antithrombotic therapy less often than rural patients for unclear reasons.
Methods and Results The charts of 597 hospitalized Medicare patients discharged between October 1, 1993, and December 31, 1994, from urban and rural hospitals in Missouri were reviewed. In addition to antithrombotic therapy prescribed at the time of discharge, patient and physician information, relative contraindications to antithrombotic therapy, and risk factors for stroke were identified. Rural and urban patients were similar in terms of age, sex, and risk factors for stroke. At least one stroke risk factor was noted in 87% of rural patients and in 84% of urban patients. Urban patients were more likely to have a relative contraindication to antithrombotic therapy compared with rural patients (66% vs 54%, P=.04) but received antithrombotic therapy more often (58% vs 47%, P=.02). Cardiologists prescribed antithrombotic therapy significantly more often than noncardiologists (69% vs 52%, P=.003).
Conclusions Elderly rural patients with atrial fibrillation receive antithrombotic therapy less frequently than urban patients despite having a similar high-risk profile and fewer relative contraindications. Primary care physicians prescribe antithrombotic therapy less often than cardiologists, which is one of the reasons for this underutilization.
Key Words: warfarin, atrial fibrillation
Poor Response to Activated Protein C as a Prominent Risk Predictor of Advanced Atherosclerosis and Arterial Disease—Kiechl S (Dept of Neurology, Innsbruck Univ Clinic, Anichstraße 35, A-6020 Innsbruck, Austria), Muigg A, Santer P, Mitterer M, Egger G, Oberhollenzer M, Oberhollenzer F, Mayr A, Gasperi A, Poewe W, Willeit J—Circulation. 1999;99:614–619. Copyright ©1999 American Heart Association Inc.
Background—The potential role of activated protein C (APC) resistance in arterial thrombosis and disease is a matter of ongoing controversy.
Methods and Results—In the present population-based survey, a random sample of 826 men and women underwent high-resolution duplex ultrasound scanning of the carotid and femoral arteries. Response to APC was expressed in APC ratios. Subjects were tested for the factor V Leiden mutation. The risk of carotid stenosis increased gradually with decreasing response to APC (adjusted OR [95% CI] for a 1-U decrease of response to APC, 1.6 [1.2 to 2.2]), as did the risk of femoral artery stenosis (1.7 [1.3 to 2.3]) and prevalent cardiovascular disease (1.4 [1.1 to 2.0]). The association between low APC ratio and atherosclerotic vascular disease applied equally to subjects with the factor V Leiden mutation and those without. Our study identified various nongenetic determinants of poor response to APC in the general population, including behavioral, hormonal, and environmental factors.
Conclusions—The present study revealed an independent and gradual association between low response to APC and both advanced atherosclerosis (stenosis) and arterial disease. Resistance to APC due to factor V Leiden mutation was only one facet of this relationship.
Key Words: risk factors, protein C
Early-Onset But Not Late-Onset Endothelin-A Receptor Blockade Can Modulate Hypertension, Cerebral Edema, and Proteinuria in Stroke-Prone Hypertensive Rats—Blezer ELA, Nicolay K, Goldschmeding R, Jansen GH, Koomans HA, Rabelink TJ, Joles JA (Dept of Nephrology and Hypertension F03.226, Utrecht Univ Hospital, PO Box 85500, 3508 GA Utrecht, Netherlands)—Hypertension. 1999;33:137–144. Copyright ©1999 American Heart Association, Inc.
The ability of endothelin receptor blockade to prevent and to treat established cerebral and renal injury was explored in salt-loaded stroke-prone spontaneously hypertensive rats (SHRSP) with the endothelin receptor subtype-A antagonist A127722. SHRSP were subjected to 1% NaCl intake. The start of treatment with A127722 (35 and 70 mg · kg−1 · d−1, respectively) was either synchronized with salt loading or initiated after the first observation of cerebral edema with T2-weighted magnetic resonance imaging. In untreated control animals median survival was 54 days (range, 32 to 80 days) after the start of salt loading. Early-onset A127722 treatment increased median survival to 233 days (range, 92 to 407 days; P<0.05 versus controls) with 35 mg/kg and to 124 days (range, 97 to 169 days; P<0.05 versus control) with 70 mg/kg. The development of cerebral edema was prevented, and systolic blood pressure and proteinuria were dose-dependently reduced. However, all rats in the 70-mg/kg treatment group developed hemorrhages in the basal ganglia shortly before death. Late-onset A127722 treatment failed to affect survival, systolic blood pressure, or proteinuria. Nevertheless, cerebral edema was reduced but not as well as in early-onset treatment. Development of hypertension, cerebral edema, and proteinuria was prevented in SHRSP when A127722 treatment was initiated at the start of salt-loading. However, A127722 treatment did not prolong survival in SHRSP with cerebral edema. This suggests that in SHRSP the endothelin A receptor participates actively in the development of increased blood pressure and initiation of organ damage but participates minimally in established malignant hypertension and progression of target-organ damage.
Key Words: endothelins, brain edema
Increased Therapeutic Efficacy With rt-PA and Anti-CD18 Antibody Treatment of Stroke in the Rat—Zhang RL, Zhang ZG, Chopp M (Henry Ford Hospital, Neurology Dept, 2799 W Grand Blvd, Detroit, MI 48202)—Neurology. 1999;52:273–279. Copyright ©1999 by the American Academy of Neurology.
Objective: To examine the efficacy of an antileukocyte adhesion antibody (anti-CD18) as an adjuvant for delayed (2 hours and 4 hours) thrombolytic therapy (recombinant human tissue plasminogen activator [rt-PA]) in middle cerebral artery occlusion (MCAO) in rats. Background: Thrombolytic therapy with rt-PA is limited in its application by a short therapeutic window. Methods: Male Wistar rats were subjected to MCAO by a single fibrin-rich clot. The rats were assigned to the following experimental groups: Experiment 1 (treatment 2 hours after embolization), 1) rt-PA, 2) anti-CD18 antibody, 3) rt-PA and anti-CD18 antibody, 4) immunoglobulin (Ig) G, and 5) vehicle; Experiment 2 (treatment 4 hours after occlusion), 1) rt-PA alone, 2) rt-PA and anti-CD18 antibody, and 3) nontreated control group. Neurologic deficits, infarction volume, hemorrhage, and brain myeloperoxidase (MPO) immunoreactivity were measured. Results: Administration of rt-PA and anti-CD18 antibody 2 hours later reduced significantly (p<0.05) the infarct volume and improved neurologic deficits compared with the vehicle-treated group. Treatment with rt-PA alone improved neurologic deficits significantly and reduced mean infarct volume compared with the vehicle-treated group. However, treatment with anti-CD18 antibody neither reduced infarct volume nor improved neurologic deficits compared with the IgG-treated group. The combination of rt-PA and anti-CD18 antibody treatment at 4 hours reduced significantly the infarct volume and MPO immunoreactive cells compared with rt-PA treatment alone at 4 hours, and reduced neurologic deficits compared with rt-PA treatment alone and compared with the nontreated animals. Conclusions: The combination of antileukocyte adhesion antibody and thrombolytic therapy may increase the therapeutic window for the treatment of stroke.
Key Words: thrombolytic therapy, plasminogen activator, tissue-type
Prospective and Retrospective Studies of Recovery in Aphasia: Changes in Cerebral Blood Flow and Language Functions—Mimura M (Dept of Neuropsychiatry, Tokyo Dental College, Ichikawa General Hospital, 5-11-13 Sugano, Ichikawa, Chiba 272, Japan), Kato M, Kato M, Sano Y, Kojima T, Naeser M, Kashima H—Brain. 1998;121:2083–2094. Copyright ©Oxford University Press 1998.
Prospective and retrospective language evaluations and single photon emission computed tomography (SPECT) scans were performed in order to study the relationship between post-stroke recovery from aphasia and changes in cerebral blood flow (CBF) in groups of patients who had made a good recovery and those who had not. For the prospective study, 20 right-handed patients with aphasia secondary to an acute cerebrovascular accident (CVA) in the left middle cerebral artery territory received language evaluations with a Japanese Standard Language Test of Aphasia (SLTA), and SPECT scans performed twice, at a mean of 3.2 and a mean of 9.2 months post-onset. Only one slice of SPECT data was analysed. A significant correlation was observed between the severity of the initial language deficit and initial CBF on the left side, but not the right. Initial CBF was not a predictor for future language recovery in either hemisphere. There was a correlation between the change in the left mean hemispheric CBF (but not the right) and the change in the overall SLTA severity rating from 3 to 9 months post-stroke. In the retrospective study, 16 right-handed patients with residual aphasia secondary to CVA in the left middle cerebral artery territory received SLTA and SPECT at a mean of 82.8 months post-onset. The patients had also received initial language evaluation with SLTA at a mean of 6.5 months post-onset. In contrast to the prospective study, the results demonstrated that the mean left hemispheric CBF at ∼7 years post-onset did not differ between good and poor recovery groups. However, the mean right hemispheric CBF of the good recovery group was higher than that of the poor recovery group in the frontal and the thalamic regions, and also in the left frontal region. The results of these complementary studies suggest that the initial language recovery within the first year post-onset may be linked primarily to functional recovery in the dominant hemisphere, where an increase in CBF was observed at 9 months post-onset. The increased perfusion adjacent to the lesion may be crucial for early recovery in aphasia. Subsequent language recovery and the long-term recovery in aphasia may be related to slow and gradual compensatory functions in the contralateral hemisphere, specifically in the homotopic frontal and thalamic areas.
Key Words: aphasia, cerebral blood flow
Efficacy of the Stump Pressure Ratio as a Guide to the Safety of Permanent Occlusion of the Internal Carotid Artery—Morishima H (Dept of Neurosurgery, St Marianna Univ School of Medicine, Yokohama City Seibu Hospital, 1197-1 Yazashi-cho, Ashai, Yokohama, Kanagawa 241-0811, Japan), Kurata A, Miyasaka Y, Fujii K, Kan S—Neurol Res. 1998;20:732–736. Copyright ©1998 Forefront Publishing Group.
To determine whether the absolute value for the stump pressure might be a useful index of symmetrical cerebral blood flow (CBF), and to examine correlations with the stump pressure ratio (initial mean stump pressure/preocclusion mean arterial pressure), fifty candidates for ICA injury or permanent occlusion were evaluated preoperatively. Each was continuously monitored for mean stump pressure and arterial pressure before, during (for a total of 20 min), and after balloon test occlusion. During the occlusion, CBF was measured by 99m Tc-hexamethyl-propyleneamine oxime (99m Tc-HMPAO) single photon emission computed tomography (SPECT). The stump pressure and the stump pressure ratio were then compared with the results of 99m Tc-HMPAO SPECT. Patients who failed to tolerate even brief periods of carotid occlusion and showed asymmetric decreases in CBF on SPECT were divided into high and moderate risk groups. Those with no significant changes in CBF on the occluded site formed the minimum risk group. Mean stump pressure was over 50 mm Hg in 10 of a total of 25 patients in the high and moderate risk groups, and below 50 mm Hg in 5 of the 25 patients in the minimum risk group. The stump pressure ratio did not exceed 56% in any but two patients in the high and moderate risk groups, and values were at least 60% in all patients of the minimum risk group. Decrease of CBF in two moderate risk group cases was localized in the posterior circulation. Difference in symmetrical CBF between the stump pressure ratio vs. the absolute value of mean stump pressure were statistically significant (p<0.01, Fisher’s Exact Test). Maintenance of a stump pressure ratio of 60% or more during test occlusion may be a more useful index for a good collateral circulation than any absolute value for mean stump pressure.
Key Words: carotid artery occlusion, collateral circulation
Interrater Reliability of Plaque Morphology Classification in Patients With Severe Carotid Artery Stenosis—Hartmann A (The Neurological Institute, Columbia-Presbyterian Medical Center, 710 West 168th St, New York, NY 10032), Mohr JP, Thompson JLP, Ramos O, Mast H—Acta Neurol Scand. 1999;99:61–64. Copyright ©Munksgaard 1999.
Objective—Ultrasonographic assessment of carotid artery plaque morphology is widely used to identify patients at high risk for stroke. However, the reliability of plaque analysis in high-grade stenosis is uncertain. We determined the interrater reliability of sonographic plaque morphology analysis is patients with severe carotid artery stenosis. Material and methods—Duplex Doppler was performed on 114 patients with 80–99% stenosis of the internal carotid artery using a Siemens Quantum 2000 D with a handheld 7.5 MHz transducer. B-mode pictures with and without color coding were printed on a Sony color video printer UP-5000 W. Three raters independently evaluated plaque echolucency, heterogeneity, calcification, and surface structure. Interrater agreement was calculated by a jackknife procedure generating kappa values and two-sided 95% confidence intervals. Results—Kappa values and 95% confidence intervals were 0.05 (−0.07 to 0.16) for plaque surface structure, 0.15 (0.02 to 0.28) for plaque heterogeneity, 0.18 (0.09 to 0.29) for plaque echogenicity, and 0.29 (0.19 to 0.39) for plaque calcification. The upper bounds of all of the confidence intervals were below the 0.40 level suggested for minimal reliability. Conclusion—The low interrater agreement indicated that unaided visual assessment of static B-mode pictures to assess plaque morphology in patients with severe carotid artery stenosis is not reliable. Other evaluation procedures and standardized criteria, as yet undeveloped, are needed to improve reliability.
Key Words: ultrasonography, Doppler, duplex, carotid arteries
The Diagnostic Value of Colour Duplex Ultrasound for Symptomatic Carotid Stenosis in Clinical Practice—Dippel DWJ (Dept of Neurology, Univ Hospital Dijkzigt, PO Box 2040, 300 CA Rotterdam, Netherlands), Kinkelder A, Bakker SLM, Kooten FV, Overhagen H, Koudstaal PJ—Neuroradiology. 1999;41:1–8. Copyright ©Springer-Verlag 1999.
We assessed the accuracy of colour duplex ultrasound for the detection of severe (70–99%) symptomatic carotid stenosis in a clinical setting, in order to assess whether it could make carotid angiography unnecessary. In 152 patients with a transient ischaemic attack or nondisabling ischaemic stroke in the carotid distribution, we compared the degree of colour duplex ultrasound stenosis with angiographic stenosis by receiver-operating-characteristic analysis. The angiograms were evaluated by blinded observers, and compared with routine reports of the colour duplex examination. We computed the sensitivity and specificity of colour duplex, and the number of angiograms and sonographic studies needed to prevent one stroke within 3 years, taking into account the risks of angiography, and the risks and efficacy of endarterectomy. The estimates were adjusted for nonverification bias. We found 34 patients (22%) with a severe (70–99%) symptomatic carotid stenosis. In 16 patients (11%) the symptomatic artery was occluded. The sensitivity and specificity of duplex ultrasound were 76% and 85%, respectively. The number of patients needed to undergo angiography to prevent one stroke was reduced from almost 200 to 33, when colour duplex was used as a preoperative examination. After adjustment for the effects of nonverification, the sensitivity dropped to 58% and the number of duplex studies needed to prevent one stroke would double. The number of angiograms needed after positive duplex sonography would be virtually unaffected. Were colour duplex sonography to have been the sole preoperative investigation, the number needed to diagnose to prevent one stroke within 3 years would be approximately 350, more than twice as many as with the combined diagnostic strategy. The diagnostic accuracy of colour duplex sonography in clinical practice seems less impressive than previous studies have suggested, but it remains an effective way to select patients for angiography. Its use as a single preoperative assessment cannot be recommended.
Key Words: carotid artery diseases, carotid endarterectomy
Second European Stroke Prevention Study: Antiplatelet Therapy is Effective Regardless of Age—Sivenius J (Dept of Neurology, Univ Hospital, PL 1777, SF-70211 Kuopio, Finland), Cunha L, Diener HC, Forbes C, Laakso M, Lowenthal A, Smets P, Riekkinen P Sr, ESPS2 Working Group—Acta Neurol Scand. 1999;99:54–60. Copyright ©Munksgaard 1999.
Background—The Second European Stroke Prevention Study (ESPS2) was a randomized, placebo-controlled trial that investigated the efficacy of low-dose acetylsalicylic acid (ASA) and modified-release dipyridamole (DP), alone or in combination, in the secondary prevention of ischemic stroke. The trial demonstrated that the combination was significantly more effective than either agent used alone. The aim of the present study was to evaluate the influence of age on the efficacy of ASA and DP, alone or in combination, in the secondary prevention of stroke in the ESPS2 population. Methods and results—A total of 6602 patients were recruited to the ESPS2 and there were 4 treatment groups: ASA (25 mg twice daily), DP (200 mg twice daily). ASA and DP in a combined formulation, or placebo. Primary endpoints were stroke, death, and stroke or death together. The endpoints evaluated in the present study were stroke, stroke and/or death, and vascular events. Stroke was the qualifying event in 76% of the patients, while 24% had a transient ischaemic attack. Patients were reviewed at 3-month intervals for 2 years. The study population consisted of 2565 (39%) patients aged less than 65 years, 2240 (34%) patients aged between 65 and 74 years, and 1797 (27%) patients aged 75 years and over. Advancing age was associated with an increased incidence of endpoints in all 4 treatment groups. The combination of ASA and DP significantly reduced the incidence of all endpoints, compared with placebo, in each age group. There was no influence of age on the efficacy of antiplatelet therapy for any of the evaluated endpoints. Relative risk reductions of treatment compared with placebo were 11.1–27.6% in the ASA group, 8.0–18.7% in the DP group, and 20.3–45.2% in patients receiving combination therapy. Conclusion—This study clearly demonstrates that combination therapy with DP and ASA is superior to either agent used alone in the secondary prevention of ischemic stroke, irrespective of the age of the patient.
Key Words: antiplatelet therapy, stroke management
Effect of Intensive Diabetes Treatment on Carotid Artery Wall Thickness in the Epidemiology of Diabetes Interventions and Complications—Epidemiology of Diabetes Interventions and Complications (EDIC) Research Group, Box NDIC/DCCT, Bethesda, MD 20892—Diabetes. 1999;48:383–390.
The Epidemiology of Diabetes Interventions and Complications (EDIC) is a multicenter longitudinal observational study of the Diabetes Control and Complications Trial (DCCT) cohort. One of the major objectives of EDIC is to study the development and progression of atherosclerotic cardiovascular disease in type 1 diabetes. In this study, we evaluated the role of cardiovascular risk factors and antecedent therapy in the DCCT on carotid intima-media wall thickness (IMT) in type 1 diabetes. At ∼18 months after the end of the DCCT, high-resolution B-mode ultrasonography was used to assess the carotid arteries of 1,325 patients with type 1 diabetes, 19–51 years of age, with duration of diabetes ranging from 6.3 to 26.1 years. An age- and sex-matched nondiabetic population (n=153) was studied with the same protocol. The ultrasound protocol was carried out in 28 EDIC clinics by centrally trained and certified sonographers using one of three scanning systems. Determination of IMT from video-taped images was performed by a single reader at the Central Ultrasound Reading Unit. Univariate associations with greater IMT were strongest for older age and longer diabetes duration, greater waist-to-hip ratio (men only), higher blood pressure, higher LDL cholesterol, and smoking. The DCCT therapy group (intensive versus conventional) and HbA1c, measured at the time of the ultrasound or the mean HbA1c during the DCCT, were not significantly related to IMT. Multivariate analyses suggest that age, height, smoking, and BMI were the major predictors of common carotid IMT, whereas age, smoking, and LDL cholesterol predicted internal carotid IMT. There were significant differences between the IMT values of the internal carotid artery in the EDIC male cohort and similarly aged male nondiabetic control subjects. There were no significant differences between the IMT values in the EDIC female cohort and similarly aged female nondiabetic control subjects. At this point in the planned 10-year follow-up of the DCCT cohort, neither intensive therapy nor HbA1c level appears to influence the early signs of atherosclerosis. Traditional risk factors, including age, smoking, and LDL cholesterol, were related to IMT. As the cohort is only now entering the age interval during which rapid progression and clinical expression of atherosclerosis are expected, further follow-up will help to determine the role of hyperglycemia, and its interaction with other risk factors, on the development of atherosclerosis.
Key Words: carotid artery stenosis, stroke prevention
Determinants of Outcome After Carotid Endarterectomy—Kucey DS (Sunnybrook Health Science Centre, 2075 Bayview Ave, H-185, Toronto, Ontario, Canada M4N 3M5), Bowyer B, Iron K, Austin P, Anderson G, Tu JV—J Vasc Surg. 1998;28:1051–1058. Copyright ©1998 by the Society of Vascular Surgery and International Society for Cardiovascular Surgery, North American Chapter.
Background: The efficacy of carotid endarterectomy for selected patients has been evaluated with randomized controlled clinical trials. The generalizability of these studies to average surgical practice remains an important public health concern.
Objective: The objective of the study was to determine the predictors of outcome after carotid endarterectomy on a regional basis.
Patients and Methods: The study was designed as a retrospective cohort study and included all consecutive patients presented for carotid endarterectomy at the 8 University of Toronto–affiliated hospitals in the period from January 1, 1994, to December 31, 1996. The main outcome measure was 30-day postoperative stroke or death rate.
Results: During the study interval, 1280 primary carotid endarterectomies were performed. The overall combined stroke and death rate was 6.3% for all patients who underwent endarterectomy (4.0% for patients who were asymptomatic). The significant predictors of poor outcome were the following: presenting symptoms (odds ratio, 1.74; 95% confidence interval [CI], 0.96, 3.12), low surgeon volume (<6 cases per year; odds ratio, 3.98; 95% CI, 1.65, 9.58), and left-sided surgery (odds ratio, 1.72; 95% CI, 1.07, 2.76).
Conclusion: These data suggest that adoption of the recommendations of the symptomatic carotid endarterectomy trials is appropriate. However, endarterectomy for asymptomatic lesions remains of uncertain benefit on a regional basis and must be individualized to the experience of the specific surgeon. The surgeon volume/outcome relationship that is identified in this study suggests a need for a minimum volume threshold for this procedure.
Key Words: carotid artery stenosis, stroke prevention
The Effects of Carotid Endarterectomy on the Retrobulbar Circulation of Patients With Severe Occlusive Carotid Artery Disease—Costa VP (Av Pacaembu, 1782 São Paulo SP CEP 01234-000, Brazil), Kuzniec S, Molnar LJ, Cerri GC, Puech-Leão P, Carvalho CA—Ophthalmology. 1999;106:306–310.
Objective: To analyze the effects of carotid endarterectomy on the retrobulbar circulation of patients with severe occlusive carotid artery disease (OCAD) by means of color Doppler imaging (CDI).
Participants: A total of 17 consecutive patients with severe OCAD and neurologic symptoms (with a history of transitory ischemic attack or cerebral vascular accident) participated.
Intervention: All 17 patients underwent carotid endarterectomy. The CDI of both orbits was performed by one masked investigator before surgery and at 1 week and 1 month after surgery.
Main Outcome Measures: Peak systolic velocity, end diastolic velocity, and resistive index of the ophthalmic, central retinal, and temporal short posterior ciliary arteries were measured. The authors compared the hemodynamic parameters at all intervals.
Results: Peak systolic and end diastolic velocities in the ophthalmic, central retinal, and temporal short posterior ciliary arteries increased significantly 1 week and 1 month after carotid endarterectomy (P<0.05). After surgery, the resistive indices in the central retinal and temporal short posterior ciliary arteries decreased significantly at both intervals (P<0.05). The six patients who had reversed ophthalmic artery flow before surgery showed forward ophthalmic artery flow after carotid endarterectomy. The contralateral orbits showed no significant hemodynamic change after endarterectomy (P<0.05).
Conclusions: Hemodynamic changes in patients with severe OCAD undergoing carotid endarterectomy suggest improvement in the ipsilateral retrobulbar blood flow.
Key Words: carotid artery stenosis, ocular disease
Items of Interest
Long-Term Antithrombotic Treatment for Atrial Fibrillation—Nademanee K (Clinical Electrophysiology and Pacing Div of Cardiology, Dept of Medicine, Univ of Southern California, 1450 San Pablo St, Suite 5501, Mailbox 5R, Los Angeles, CA 90033), Kosar EM—Am J Cardiol. 1998;82:37N–42N. Copyright ©1998 by Excerpta Medica, Inc.
The Relationship Between Poststroke Depression and Lesion Location in Long-Term Follow-Up—Shimoda K, Robinson RG (Dept of Psychiatry, Univ of Iowa, 200 Hawkins Dr, 2887 JPP, Iowa City, IA 52242)—Biol Psychiatry. 1999;45:187–192. Copyright ©1999 Society of Biological Psychiatry.
Oxidative Stress in Brain Ischemia—Love S (Dept of Neuropathology, Frenchay Hospital, Bristol BS16 1LE, UK)—Brain Pathol. 1999;9: 119–131.
Antioxidant Therapy Against Cerebral Vasospasm Following Aneurysmal Subarachnoid Hemorrhage—Asano T (Dept of Neurosurgery, Saitama Medical Center/School, 1981 Kamoda Kawagoe, Saitama 350, Japan), Matsui T—Cell Mol Neurobiol. 1999;19:31–44. Copyright ©1999 Plenum Publishing Corporation.
Increased Intimal-Medial Thickness in Newly Detected Type 2 Diabetes—Temelkova-Kurktschiev TS (Institute and Outpatient Clinic for Clinical Metabolic Research, Technical Univ, Dresden, Germany), Koehler C, Leonhardt W, Schaper F, Henkel E, Siegert G, Hanefeld M—Diabetes Care. 1999;22:333–338.
Conventional Cerebral Angiography in Children With Ischemic Stroke—Ganesan V (Newcomen Centre, Guys Hospital, Saint Thomas St, London SE1 9RT, UK), Savvy L, Chong K, Kirkham FJ—Pediatr Neurol. 1999;20:38–42. Copyright ©1999 by Elsevier Science Inc.
The abstracts in this section have been typeset for consistency with journal format but otherwise appear as in the original articles.
- Copyright © 1999 by American Heart Association