Asymptomatic bruit, carotid and vertebrobasilar transient ischemic attacks--a clinical and ultrasonic correlation

One hundred patients with asymptomatic carotid bruit or transient ischemic attack (TIA) underwent continuous-wave Doppler (CWD) and real time ultrasound (RTU) testing of their cervical carotid arteries. After ultrasonic studies, 51 patients also underwent bilateral carotid angiography. There was 95% agreement between CWD and angiography for the diagnosis of a significant (greater than 50%) stenosis. The RTU diagnosis of a normal or occluded vessel was correct in 100% of cases. Seven plaques appreciated on RTU may not have been large enough for detection by angiography. In this small series, ulceration confirmed pathologically was more reliably predicted by RTU than by cerebral angiography. Significant ipsilateral carotid plaques occurred more often in patients with amaurosis fugax than in patients with hemispheric TIAs. Ipsilateral plaque ulceration occurred in 50% of symptomatic carotid bruits, but in only 10% of asymptomatic carotid bruits. Plasma concentrations of total cholesterol were significantly higher in TIA patients with carotid stenosis than in controls.     

Arteriographic comparison of amaurosis fugax and hemispheric transient ischaemic attacks

The results of carotid angiography were compared in 53 patients with amaurosis fugax and 92 with hemispheric transient ischaemic attacks (TIAs). Evidence of extracranial disease was found in 71% of those with retinal ischaemia and these patients rarely had evidence of intracranial disease (11%) or normal angiograms (15%). By contrast patients with hemispheric symptoms less frequently showed disease of the cervical carotid artery (36%) and more often had intracranial disease (27%) or normal angiograms (35%). It is suggested that amaurosis fugax is usually due to emboli originating in the internal carotid artery but that the pathogenesis of cerebral TIAs in the carotid territory is more heterogeneous. These conclusions have implications for the design and interpretation of both medical and surgical trials.     

Mortality and stroke after amaurosis fugax.

One hundred and ten patients who had presented with amaurosis fugax and were treated medically were studied retrospectively. Follow up from the time of presentation was six to nineteen years with a median of eight years. The mortality and frequency of strokes in this group was compared with populations matched for age and sex. Life expectancy in patients with amaurosis fugax was reduced. Ischaemic heart disease was the most frequent cause of death and occurred at a greater rate than in the general population (p less than 0.01). The indicence of stroke was higher than in the Oxfordshire Community Stroke Project 1981-1983 (p less than 0.01). Comparing our results to those published for cerebral transient ischaemic attacks, patients with amaurosis fugax have a similar mortality rate but probably have a lower incidence of stroke. Patients with amaurosis fugax who have an occluded or narrowed proximal internal carotid artery have a greater risk of subsequent stroke than those with a normal carotid artery, or an arteriogram (p less than 0.01).     

Placement of stent for internal carotid artery stenosis in the cervical portion improved ocular ischemic syndrome]

We report a case of ocular ischemic syndrome due to severe stenosis of the internal carotid artery. The patient was a 67-year-old man with a hemispheric transient ischemic attack and an amaurosis fugax. Ocular examination showed multiple soft exudates and dilatation of the retinal veins. Carotid stenting was performed to reconstruct the internal carotid artery. The multiple soft exudates were almost diminished and the visual acuity was improved. These results suggest that carotid stenting for severe stenosis of the internal carotid artery should be one of the less invasive methods to improve the microcirculation of the retina.     

Bilateral stenting of symptomatic and asymptomatic internal carotid artery stenosis due to fibromuscular dysplasia

Stent grafting of internal carotid artery (ICA) stenoses due to fibromuscular dysplasia has been rarely and only unilaterally carried so far. Bilateral carotid stent grafting of ICA stenoses due to fibromuscular dysplasia has not been reported previously. In a 37 year old woman with recurrent right hemispheric transitory ischaemic attacks, a non-disabling minor stroke, and recurrent right amaurosis fugax despite antithrombotic therapy, cerebral angiography disclosed a long segment narrowing, distal, high grade (95%) stenosis of the right ICA and a long narrowing, distal high grade (70%) stenosis of the left ICA. Morphological features of both stenoses were indicative of fibromuscular dysplasia. The right sided stenosis was stented with a PTFE-HEMOBAHN endoprosthesis; this was followed by a brief, postprocedural left sided hemiparesis. The left sided ICA stenosis was successfully stented by the same procedure. Nine months later, both stents were still patent and the patient was symptom free. Bilateral carotid stenting may remain an alternative to endarterectomy in bilateral ICA stenosis due to fibromuscular dysplasia when ischaemic events persist despite full antithrombotic therapy.     

Amaurosis fugax: a clinical comparison.

Amaurosis fugax (transient monocular blindness) is a symptom of retinal ischemia just as contralateral hemiparesis and sensory loss are symptoms of cerebral ischemia. These symptoms are produced by atherosclerotic stenosis of the carotid vessels at the ipsilateral carotid bifurcation and emboli from these areas causing focal, repetitive, retinal ischemia. A study of 31 endarterectomy patients was undertaken to see if eight patients with amaurosis fugax (25%) could be differentiated from 22 patients with transient cerebral ischemia. The patients with amaurosis fugax were found to be younger. They all had 75% or greater stenosis of the internal carotid artery at the bifurcation on the symptomatic side. They all had unilateral visual symptoms and these symptoms were relieved by surgery. The patients with amaurosis fugax were devoid of cardiac disease, while 45% of the cerebral ischemic patients had documented myocardial disease. Amaurosis fugax (transient monocular blindness) in the setting of clinically significant atheroslerosis of the carotid vessels is an indication for carotid endarterectomy.     

Dual isotope carotid scintigraphy in patients with amaurosis fugax attacks

Summary A new dual isotope scintigraphic (DISC) examination of the carotid arteries consisting of simultaneous injections of ¹¹¹In-labeled platelets and ^99mTc-labeled red cells was performed on eight male patients suffering from amaurosis fugax attacks. In concordance with the angiographically proven high percentage of significant extracranial carotid disease in patients with amaurosis fugax, six of the eight patients examined had an increased platelet accumulation in the carotid artery clinically affected. In one patient with normal angiography and one amaurosis fugax attack the platelet scintigraphy even revealed a pathological platelet accumulation in the ipsilateral carotid artery. These findings confirm the hypothesis that most amaurosis fugax attacks are due to arterio-arterial emboli originating from atherosclerotic plaques of the carotid bifurcation.     

一过性黑朦患者临床及颈动脉狭窄特点分析

目的分析一过性黑朦（amaurosis fugax,AmF）患者临床及颈动脉狭窄的特点,探讨其与脑梗死发生的关系。方法对34例一过性黑朦患者的临床资料进行分析,应用彩色多普照勒颈动脉超声及经颅多普勒超声（TCD）检查颈动脉硬化、狭窄及眼动脉血流方向情况。结果34例AmF患者中有25例（73.5%）以AmF为首发症状,29例（85.3%）为单眼AmF发作,左右两眼发病率无统计学差异（P〉0.05）,70.6%的患者在AmF发作后3个月内发生脑梗死。超声检查显示AmF患者患侧颈动脉内膜增厚伴斑块发生率（82.4%）高于对侧（29.4%,P〈0.05）。颈动脉重度以上狭窄占91.2%,患侧颈内动脉狭窄或闭塞发生率（27例,79.4%）明显高于对侧（10例,29.4%,P〈0.05）。TCD检查显示眼动脉侧支开放14例,无眼动脉侧支20例。眼动脉侧支开放组颈动脉中度以上狭窄发生率（92.9%）与侧支未开放组颈动脉狭窄发生率（70.0%）无明显差异（P〉0.05）。经Logistic回归分析,有短暂性脑缺血病史（OR0.38,95%CI0.07-0.69,P=0.02〈0.05）和颈动脉严重狭窄（OR0.33,95%CI0.08-0.58,P=0.01〈0.05）是AmF发作后近期发生脑梗死的独立危险因素。结论AmF往往提示颈内动脉存在严重狭窄,严重的颈内动脉狭窄是引起AmF的主要原因。伴有短暂性脑缺血病史及颈动脉严重狭窄的AmF患者近期容易发生脑梗死。     

Visual disturbance and carotid artery disease. 500 symptomatic patients studied by non-invasive carotid artery testing including B-mode ultrasonography

Non-invasive carotid artery testing was performed on 500 consecutive patients with visual disturbances not related to local ophthalmic pathology to determine the extent of carotid artery disease, particularly in patients with symptoms not typical of amaurosis fugax. Three hundred eighty six patients (77.2%) had an abnormal study. However, the incidence of hemodynamically significant lesions was only 16%. The patients could be divided into three groups: Patients with symptoms that could be explained on an ocular basis, including amaurosis fugax, had a 79% incidence of ipsilateral carotid plaques. Patients with symptoms which could not be easily explained on an ocular basis, such as bilateral blurred vision, bilateral visual loss (both transient and permanent), and homonymous hemianopsia had an incidence of carotid artery plaques similar to patients with amaurosis fugax. Patients with unilateral blurred vision and bilateral scintillations had a lower incidence (57%) of carotid plaques than the other groups. Younger symptomatic patients had less carotid plaques than the overall series. Twenty-one percent of patients under age 50 had the Doppler finding of early systolic flutter turbulence, which is usually of mitral valve origin. Women predominated in the under 50 age group by about 2:1. In view of the prevalence of carotid plaques in the population of patients with visual symptoms other than amaurosis fugax, evaluation of these patients with non-invasive testing is indicated to determine which of these patients has hemodynamically significant obstruction to flow at the carotid artery bifurcation.     

Plaque morphology correlates with cerebrovascular symptoms in patients with complex aortic arch plaque

BACKGROUND: Studies of aortic arch plaques with transesophageal echocardiography have demonstrated that complex aortic arch plaques (CAPs) greater than or equal to 4 mm in thickness are associated with ischemic stroke. Recent studies have demonstrated that the morphological features of plaques may aid in the identification of aortic plaques that are more likely to be associated with embolic stroke. OBJECTIVE: To identify aortic plaques that are more likely to be associated with embolic stroke by means of their morphological features. METHODS: Transcutaneous B-mode ultrasonography was used to image aortic arch plaques in 500 consecutive patients. The criteria used to identify the morphological features of carotid artery plaques that are more likely to be associated with ischemic stroke (heterogeneous rather than homogeneous) were applied to aortic arch plaques. Statistical comparisons were made using the Fisher exact test. RESULTS: Ischemic symptoms (eg, stroke, transient ischemic attack, and amaurosis fugax) were present in 38% of 104 patients with CAP and in 34% of 391 patients without CAP. Nineteen (51%) of 37 patients with heterogeneous CAP were symptomatic. Twenty-one (31%) of 67 patients with homogeneous CAP were symptomatic (P = .04). CONCLUSION: Transcutaneous B-mode ultrasonography of the aortic arch can help to identify heterogeneous plaques that are more likely to be associated with ischemic stroke using morphological criteria derived from studies of carotid artery plaque.     

Duplex scanner study of carotid artery dissection following surgical treatment of aortic dissection type A

In patients suffering from aortic dissection, persistent perfusion of the false lumen distal to the implanted graft is frequent. Postoperative follow-up examinations of the carotid arteries of these patients were performed by duplex scanner and correlated with clinical symptoms. Thirty-nine patients who survived the surgical treatment of acute type A aortic dissection had duplex sonography of both common carotid arteries after an average postoperative follow-up of 53 months. In 21 cases a composite graft and in 18 cases a supracoronary prosthetic vascular graft were implanted. No sign of residual dissection of the common carotid arteries was seen in 23 patients; in nine there was a dissection of both common carotid arteries, and seven patients had a unilateral carotid dissection (five right, two left). There were nine symptomatic patients with the following symptoms: transient ischemic attack (four), amaurosis fugax (four), stroke with incomplete recovery (one). Two symptomatic patients had a corresponding dissection. The generally good prognosis of all these patients suggests a conservative nonoperative treatment.     

Transient visual symptoms and carotid artery disease. Exploration by real-time B-mode echotomography

The real-time B-mode echotomographies of 100 patients with transient visual symptoms have been reviewed and their findings have been compared with those of other 100 patients with transient ischemic attacks, who never had visual disturbances in their clinical history. The rate of pathologic echotomographies was higher in the group of patients with transient visual symptoms (72%), who also had a higher percentage (50% of the positive cases) of small or mild plaques without significant hemodynamic effects. The amaurosis fugax, particularly when associated with hemispheric ischemic symptoms, should suggest a carotid disease. The non-invasive exploration by real-time B-mode echotomography and Doppler with spectral analysis is the method of choice for the diagnosis of patients with transient visual symptoms.     

Mechanisms of retinal arterial occlusive disease in African American and Caucasian patients.

BACKGROUND AND PURPOSE: The aim of our study was to evaluate the causes of retinal arterial occlusive disease in African American patients and to compare these etiologies with those observed in Caucasian patients with retinal ischemic symptoms. METHODS: We performed a retrospective analysis of a series of consecutive patients evaluated by both the ophthalmology department and the neurology/stroke clinic. Patients had a diagnosis of amaurosis fugax, branch retinal artery occlusion, central retinal artery occlusion, or intra-arterial retinal plaques. RESULTS: Twenty-nine African American patients and 17 Caucasian patients were evaluated. African American patients had a mean age of 61 years (range, 30 to 77 years) and Caucasian patients a mean age of 73 years (range, 56 to 94 years) (P=0.003). There was no statistically significant difference between the 2 groups with respect to visible emboli on funduscopy (P=0.462). After adjusting for age, there was also no difference between the 2 groups with regards to risk factors for arterial occlusive disease such as hypertension, coronary artery disease, hypercholesterolemia, tobacco use, and history of stroke or transient ischemic attacks. Caucasian patients had a 41% incidence (7/17) of high-grade ipsilateral internal carotid artery stenosis, measured by carotid duplex, compared with 3.4% incidence (1/29) in African American patients (P=0.002). CONCLUSIONS: There are racial differences in the causes of retinal arterial occlusion. African American patients have a low prevalence of moderate to severe extracranial carotid stenosis, and a high proportion of African American patients have cryptogenic retinal ischemia. In Caucasian patients there is a stronger association between extracranial carotid artery disease and retinal arterial occlusion.     

Enteric-coated acetylsalicylic acid plus dipyridamole compared with anticoagulants in the prevention of ischemic events in patients with transient ischemic attacks

From December 1976 through March 1982, 188 patients entered an open non-random study carried out on hospitalized patients with a history of transient ischemic attacks or amaurosis fugax. Ninety-two patients received peroral anticoagulants usually combined with heparin treatment during the first days of treatment, and 96 patients enteric-coated acetylsalicylic acid 0,5 g twice daily plus dipyridamole 75 mg twice daily. The patients were followed up to March 1983, irrespective of whether treatment was changed or not. Recurrent transient ischemic attack or amaurosis fugax occurred more frequently (P less than 0.01) from 2 months of follow-up and throughout the observation period in the antiplatelet-treated group. There were no statistically significant differences between the 2 groups on the originally given treatment for endpoints such as stroke (6 patients on anticoagulants, 12 patients on antiplatelet therapy) or stroke or death (11 patients on anticoagulants, 17 patients on antiplatelet therapy). The findings from this trial suggest that anticoagulant treatment is superior to antiplatelet therapy given in the prevention of ischemic attacks and that this difference mainly exists during the first one to 2 months after onset of transient ischemic attacks or amaurosis fugax.     

Amaurosis fugax in a Danish community: a prospective study

A prospective study of amaurosis fugax was carried out in a Danish community (population 481,000); case ascertainment was based on the collaboration of practicing ophthalmologists and general practitioners. Over a 3-year period we registered 131 cases; the annual incidence of "first amaurosis fugax episodes coming to medical attention" was 8.6 and 6.2 per 100,000 population for men and women, respectively. On the basis of a comparison of the age-incidence curves for cerebral and retinal ischemic attacks, the "true" incidence of amaurosis fugax is estimated to be approximately 14/100,000/yr, or 25-30% of the reported incidence of transient ischemic attacks. Clinical and/or radiologic signs of a carotid lesion on the appropriate side were present in 56% of the patients, and an additional 27% had symptoms or signs of other organic cardiovascular disorders. Forty-three (68%) of the 63 patients who underwent arteriography had an atheromatous lesion apparently amenable to carotid endarterectomy. In spite of the case-finding procedures employed in the study, cases of amaurosis fugax suitable for carotid surgery were thus ascertained at a rate of only 3/100,000/yr. This suggests that surgical treatment of patients with retinal ischemic attacks is of minor importance as a preventive measure against stroke in the community.     

Clinical and arteriographic comparison of amaurosis fugax with hemispheric transient ischemic attacks

Eighty-seven patients with either amaurosis fugax (40 patients) or hemispheric transient ischemic attacks (47 patients) were studied to determine whether the two symptom groups could be differentiated clinically and arteriographically. Clinical data assessed were age of patient, incidence of cardiac disease, and presence of claudication, hypertension, diabetes, and carotid bruits. Contrary to a prior report, our results indicate no significant difference between the 2 patient groups based on clinical and arteriographic findings.     

Restenosis after carotid artery stenting and endarterectomy: a secondary analysis of CREST, a randomised controlled trial

BACKGROUND: In the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST), the composite primary endpoint of stroke, myocardial infarction, or death during the periprocedural period or ipsilateral stroke thereafter did not differ between carotid artery stenting and carotid endarterectomy for symptomatic or asymptomatic carotid stenosis. A secondary aim of this randomised trial was to compare the composite endpoint of restenosis or occlusion. METHODS: Patients with stenosis of the carotid artery who were asymptomatic or had had a transient ischaemic attack, amaurosis fugax, or a minor stroke were eligible for CREST and were enrolled at 117 clinical centres in the USA and Canada between Dec 21, 2000, and July 18, 2008. In this secondary analysis, the main endpoint was a composite of restenosis or occlusion at 2 years. Restenosis and occlusion were assessed by duplex ultrasonography at 1, 6, 12, 24, and 48 months and were defined as a reduction in diameter of the target artery of at least 70%, diagnosed by a peak systolic velocity of at least 3·0 m/s. Studies were done in CREST-certified laboratories and interpreted at the Ultrasound Core Laboratory (University of Washington). The frequency of restenosis was calculated by Kaplan-Meier survival estimates and was compared during a 2-year follow-up period. We used proportional hazards models to assess the association between baseline characteristics and risk of restenosis. Analyses were per protocol. CREST is registered with ClinicalTrials.gov, number NCT00004732. FINDINGS: 2191 patients received their assigned treatment within 30 days of randomisation and had eligible ultrasonography (1086 who had carotid artery stenting, 1105 who had carotid endarterectomy). In 2 years, 58 patients who underwent carotid artery stenting (Kaplan-Meier rate 6·0%) and 62 who had carotid endarterectomy (6·3%) had restenosis or occlusion (hazard ratio [HR] 0·90, 95% CI 0·63-1·29; p=0·58). Female sex (1·79, 1·25-2·56), diabetes (2·31, 1·61-3·31), and dyslipidaemia (2·07, 1·01-4·26) were independent predictors of restenosis or occlusion after the two procedures. Smoking predicted an increased rate of restenosis after carotid endarterectomy (2·26, 1·34-3·77) but not after carotid artery stenting (0·77, 0·41-1·42). INTERPRETATION: Restenosis and occlusion were infrequent and rates were similar up to 2 years after carotid endarterectomy and carotid artery stenting. Subsets of patients could benefit from early and frequent monitoring after revascularisation. FUNDING: National Institute of Neurological Disorders and Stroke and Abbott Vascular Solutions.     

Computed tomography in patients with transient ischaemic attacks: when is a transient ischaemic attack not a transient ischaemic attack but a stroke?

Summary In a prospective community-based study, 184 patients with transient ischaemic attacks (TIAs) were identified from a study population of about 105,000 between 1981 and 1986. Computed tomography (CT) was attempted in all those with cerebral ischaemic attacks (n=152, 83%); patients with amaurosis fugax only (n=32, 27%) were not scanned routinely. Scans were obtained in 120 (79%) of those with cerebral attacks and 12 (38%) of those with amaurosis fugax. The scans were reported by a neuroradiologist who was blinded to the patients' clinical features. Of 120 (27% :95% confidence interval 19–35) scans in patients with cerebral attacks, 32 showed a focal area of hypodensity or cortical loss, but in only 14 (12% :95% confidence interval 6–18) was this in an area of the brain appropriate to the patients' symptoms. There were no significant differences in the clinical features, the duration of attacks or the prognosis (i.e, risk of death, stroke or myocardial infarction) of patients with and without ischaemic lesions on CT. It is concluded that patients with clinically definite TIAs who have a presumed ischaemic and appropriately sited lesion on CT should not be re-classified as having had a stroke.     

Carotid endarterectomy. Clinical results in a community-based teaching hospital

Since 1971, 688 consecutive carotid endarterectomies were performed in 612 patients in a community-based teaching hospital by 16 surgeons; 82% of the procedures were performed in patients who had suffered a transient ischemic attack, amaurosis fugax, or a previous stroke. Seven patients (1%) died, five of perioperative stroke and two of myocardial infarction. Thirty-one patients suffered a perioperative stroke (4.5% of the 688 endarterectomies); 20 patients (2.9% of 688) were left with moderate to severe neurologic deficits. The combined mortality/major neurologic deficit morbidity rate (number of patients divided by number of endarterectomies) is 3.2%. Both operative mortality and morbidity have progressively declined in successive 5-year periods, with no deaths and a 2.7% stroke rate in 148 endarterectomies performed after 1984. Our results indicate that carotid endarterectomy as practiced in a community-based teaching hospital can be performed without excessive risk.     

Coagulation activation and ultrasound characteristics in patients with carotid artery disease

Introduction

Elevated levels of markers for thrombin activation are associated with plaque echogenicity and degree of stenosis in patients with carotid artery stenosis. The Activated Protein C-Protein C Inhibitor (APC-PCI) complex reflects activation of the Protein C system and is a measure of thrombin generation. The aim of the present study was to examine APC-PCI complex in patients undergoing thrombendartherectomy for carotid artery stenosis, and to relate the findings to clinical characteristics and plaque morphology as determined by ultrasound.

Materials and Methods

Blood was obtained from 125 patients (39 female, median age 71 years) with carotid artery stenosis admitted from September 2005 to May 2007. The APC-PCI complex was measured using a sandwich immunofluorometric method and compared to an age- and sex-matched healthy control-group. Clinical and demographic characteristics, routine laboratory markers and ultrasound characteristics were analysed using univariate and multivariate analysis.

Results

APC-PCI complex concentration was significantly increased in patients with carotid artery stenosis (median 0.21 µg/L; 10th to 90th percentile 0.15-0.36) compared to a healthy control-group (0.19 µg/L; 0.11-0.31; P = .009). There was no significant difference in APC-PCI-values between asymptomatic (n = 48) and symptomatic (n = 77) patients with carotid artery stenosis (0.22 vs. 0.20 µg/L; p = 0.626). Patients with minor stroke (n = 31) had a higher median APC-PCI-concentration (0.27 µg/L; 0.15-0.63) than patients with amaurosis fugax (0.19 µg/L; 0.15-0.36) or transient ischemic attack (0.21 µg/L; 0.12-0.36) (p = 0.016). No association was found between APC-PCI-values and the degrees of carotid artery stenosis or the time from the latest neurological symptoms to blood sampling. Patients with echolucent plaques had significantly lower APC-PCI concentrations (0.20 µg/L; 0.14-0.35 vs. 0.24 µg/L; 0.15-0.60; p = 0.043), according to the Gray-Weale classification.

Conclusions

Patients with carotid artery disease exhibit increased concentrations of APC-PCI compared to a healthy control-group, particularly those patients with echogenic plaques, who have significantly higher APC-PCI levels than patients with echolucent plaques.