Carotid Transient Ischemic Attacks Research Articles

Early Carotid Endarterectomy for Symptomatic Stenosis of Internal Carotid Artery in Patients Affected by Transient Ischemic Attack or Minor-to-Moderate Ischemic Acute Stroke: A Single-Center Experience

In the setting of carotid transient ischemic attack (TIA) or minor/moderate ischemic stroke, early surgical endarterectomy (CEA) seems to decrease the number of recurrences. The aim of the present study was to report a single-center experience with early surgical carotid revascularization in patients affected by TIA and minor/moderate ischemic acute stroke. A retrospective data collection was carried out on all consecutive patients surgically treated for an extracranial internal carotid artery (ICA) hemodynamic NASCET stenosis in the Vascular Unit of Foch Hospital, in Suresnes (France) between January 2011 and July 2016. All patients undergoing ICA endarterectomy for symptomatic carotid stenosis (SCS) within 48 hours and 14 days after the acute neurologic onset were included in the present study. Outcomes were evaluated by a prospective follow-up. Primary outcomes were the rate of postoperative ipsilateral stroke and myocardial infarction (MI) and the death/stroke/MI at 30-day and at the long-term follow-up. Secondary outcomes were local and systemic complications' rate. Outcomes were stratified according to NIHSS score and comorbidities, and a univariate analysis and multivariate analysis were performed to define any correlation between preoperative data and postoperative outcomes. A total of 249 consecutive patients (45.4%, 113 symptomatic vs. 54.6%, 136 asymptomatic) underwent CEA for hemodynamically significant ICA stenosis at our institution. According to inclusion criteria, 72 patients affected by SCS (27.7% women vs. 72.3% men; median age 71.9 years, range: 42-89; median preoperative NIHSS score 3, range 1-17) were enrolled in the present study. Median delay for surgery was 4 days (range: 2-14). No in-hospital stroke, nor myocardial infarction nor death were detected during in-hospital post-operative period. The combined death/stroke/MI rate was 0% and 5.5 % at 30-days at 6 years follow-up respectively. In-hospital NIHSS score improved post-operatively of more than 2 points (range 0-15) in 47.2% of cases. A total of 10 patients (13.8%) experienced a local complication (hematoma, permanent or regressive nerve injury). No systemic complications (renal/respiratory failure, urinary tract infection, pneumoniae) were registered. At long-term follow-up a total of four patients (5.5%) died and six patients (8.3%) were lost. The stratification of outcomes according to NIHSS status, sex, comorbidities and preoperative surgical procedure did not show any statistical relation neither at 30 days nor at the long term-follow up. Diabetes was statistically correlated to a higher rate of complication at the long-term follow-up (P 0.049). In properly selected patients affected by minor/moderate ischemic acute stroke and TIA early carotid endarterectomy can be performed without any worsening of neurological status.

Influential factors and clinical significance of fluid-attenuated inversion recovery vascular hyperintensities in transient ischemic attacks of carotid arterial system.

Fluid-attenuated inversion recovery vascular hyperintensity (FVH) is often observed in conjunction with acute ischemic stroke (AIS) of the carotid system. Despite its bearing on patient care outcomes, factors influencing FVH and its clinical significance in patients with transient ischemic attacks (TIAs) of the carotid arterial system have yet to be evaluated. Consecutive inpatients (N=154) diagnosed with TIAs of the carotid system in a 2-year period (2012-2014) were enrolled in our study. Each had undergone magnetic resonance imaging (MRI) within 72h of symptom onset, followed by intracranial and extracranial vascular imaging. We investigated the frequency and nature of factors associated with FVH, also examining its clinical significance in the 30-day prognosis of TIA. Of the 154 patients enrolled (male, 92; mean age 63.0±11.9), FVH was confirmed in 61 patients (39.6%). In logistic regression analysis, intracranial large-artery disease (LAD) (OR=2.39, 95% CI 1.16-4.92; p=0.018) and prior stroke (OR=3.33, 95% CI 1.48-7.51; p=0.004) emerged as factors independently associated with FVH positivity. Ultimately, 25 patients (16.2%) progressed to AIS within a 30-day follow-up period. Logistic regression analysis indicated that contralateral FVH positivity (OR=5.98, 95% CI 1.81-19.76; p=0.003), atrial fibrillation (OR=7.05, 95% CI 1.33-37.40; p=0.022), and extracranial LAD (OR=4.12, 95% CI 1.26-13.41; p=0.019) were independently associated with AIS during the 30-day follow-up of TIAs in these patients. Intracranial LAD and previous stroke are independently associated with FVH in patients experiencing carotid system TIAs. If present, FVH may predict an oncoming AIS in the 30days following a TIA.

THE STRUCTURAL FEATURES OF VASCULAR ENDOTHELIUM IN ACUTE CEREBRAL ISCHEMIA

The aim of the research was to study the number and structural properties of desquamated endothelial cells (DECs) in the peripheral blood in carotid ischemic stroke (CIS) and carotid transient ischemic attacks (TIAs) and its connection with the marker of endothelial dysfunction - endothelin-1. We examined 35 patients with the first CIS, on days 1st and 10th, and also 34 patients with symptomatic carotid TIAs, on days 1st and 10th of the observation. Middle age of the examined patients with a CIS was 63,7±1,0. Middle age of the examined patients with the ТIАs was 54,7±1,0. 25 practically healthy persons were examined as a group of control. Neurologic deficit was assessed with the National Institutes of Health Stroke Scale (NIHSS). DECs were estimated by CD34 immunobead capture in the peripheral venous blood of patients and persons of control group. We studied the level of endothelin-1 in the peripheral venous blood of patients and persons of control group using the enzyme immunoassay using the Biomedica (Austria) during the first 24 hrs and on day 10. Statistical processing of the obtained results was carried out using statistical analysis package Statistica. In this case, the mean value, the standard error and the correlation analysis were determined. Samples were compared using the Student's criterion (t) and the correlation coefficient (r). During an examination of 35 patients in the acute period of CIS and 34 patients with carotid TIAs using the immunocytochemical method the number of DECs was studied in venous blood. The quantitative analysis of vascular endothelium in acute cerebral ischemias showed its statistically unreliable differences in CIS and TIAs. A conclusion is drawn about the general mechanisms of endothelial dysfunction in CIS and TIAs. The number of DECs significantly correlates with the terms of disease. Regress of this indicator is noted in patients by the end of follow-up in both observation groups. During the first 24 hrs in patients with CIS and TIAs density of DECs of blood directly correlates with the level of endothelin-1 blood. The endothelin-1 level tends to decrease by the 10th day of observation and the correlation force with the DECs level is correspondingly reduced.

Abstract WP288: Variations in the Reliability of ICD-9-CM Codes by Hospital Characteristics and Stroke Severity: The Paul Coverdell National Acute Stroke Program

Background: ICD-9-CM codes recorded in administrative databases are often used to identify patients with specific clinical conditions. We determined if there are variations in the accuracy of stroke and transient ischemic attack (TIA) ICD-9-CM codes based on hospital characteristics and stroke severity. Methods: We used the records of patients discharged from hospitals in the Paul Coverdell National Acute Stroke Program in 2013. Diagnosis categories included ischemic stroke, TIA, subarachnoid hemorrhage, and intracerebral hemorrhage. We compared the agreement between the principal ICD-9-CM code and attending physician’s clinical diagnosis. The effects of hospital characteristics and stroke severity (National Institutes of Health Stroke Scale score, NIHSS) on percent agreement were assessed. Results: Among 67,442 patient records with hospital characteristic data, agreement between ICD-9-CM codes and the clinical diagnosis for ischemic stroke was higher for hospitals with stroke units, stroke teams, larger numbers of beds, and locations in metropolitan areas (P<0.05) (Table). For 55,373 records with a documented NIHSS at admission, agreement was lower for mild ischemic strokes (NIHSS 0-7) compared with more severe strokes (P<0.001); disagreements were commonly due to the patient having a carotid endarterectomy (potentially reflecting continuity of care for a stroke event) or TIA rather than a stroke. Conclusion: Systematic variations in the accuracy of ICD-9-CM codes by hospital characteristics and stroke severity may affect case identification in epidemiologic studies and have implications for hospital-level quality metrics.

Color Duplex Sonography Findings of the Carotid Arteries and Associated Risk Factors in Patients with Transient Ischemic Attack

Abstract Introduction. A transient ischemic attack (TIA) is an acute episode of temporary neurologic dysfunction that typically lasts less than an hour. Atherosclerotic plaques in the carotid arteries may cause TIA by lumen stenosis or plaque-related thromboembolism. The aim of this paper was to analyze the changes of the carotid arteries in patients with TIA and associated risk factors. Methods. A retrospective analysis of 62 TIA patients was performed. Color duplex sonography of the carotid arteries and risk factor assessment was carried out in all patients. Results. We analyzed 15(24%) females and 47(76%) males with TIA, aged 45-79 years. The most frequent risk factor was hypertension, present in 57 patients (91.9%). The most common findings of the extracranial segments of the carotid arteries were atheromatous plaques present in 25.8% and low-grade stenosis (40-59%) visualized in 24.1% of patients. Multiple plaques predominated, mostly localized in the region of bifurcation and the beginning of the internal carotid artery (67.7%), with irregular surface (in 58.1%), heterogenous structure (70.9%) and mostly hypoechogenic (46.8%). Conclusion. These data have demonstrated a significant relationship between carotid artery ultrasound plaque characteristics and TIA occurrence. That is why color duplex sonography of the carotid arteries should be carried out in all TIA patients and risk factors should be evaluated, in order to take appropriate therapeutic measures for prevention of definitive stroke.

Pathological laughter as prodromal manifestation of transient ischemic attacks—case report and brief review

BackgroundBased on a case report, the authors reviewed the data about involuntary emotional expression disorder (IEED). IEED includes the syndromes of pathological laughing and crying (PLC) and emotional lability (EL). PLC is a rare disorder of emotional expression characterized by relatively uncontrollable episodes of laughter and crying or both that do not have an apparent motivating stimulus.Case presentationAuthors report the case of a 59-year-old man who presented with recurrent episodes of PLC of approximately 2 min duration, consisting of accelerated breathing, emission of guttural, snoring sounds, frowning of the eyebrows, followed by laughter accompanied by motor restlessness of all four limbs. PLC episodes preceded left carotid transient ischemic attacks (TIA’s) manifested by reversible aphasia and right hemiparesis. Electroencephalography performed during PLC episodes revealed no spike-wave activity. Brain magnetic resonance imaging showed lacunar infarcts in the left lenticulo-capsulo-thalamic area and multiple round lesions in the cortical-subcortical and in the deep white matter of frontal-parietal-occipital lobes bilaterally, with T2 hyperintensity, T1 isointensity and no diffusion changes. The episodes were interpreted as transient ischemic attacks although gelastic seizures could not be excluded. The etiological investigations revealed unstable plaques on the left carotid artery bulb and the aortic arch and a degenerative mitral valve stenosis. The patient was treated first with antiplatelet therapy and antiepileptic drugs but PLC stopped only after anticoagulation was started. During follow-up the patient continued to have left carotid and vertebrobasilar TIA’s being on oral anticoagulation. The patient became asymptomatic only after mitral valve replacement was performed.ConclusionsThis case illustrates the difficulty distinguishing between gelastic epilepsy and TIA’s in cases of PLC episodes and discuss the neuroanatomic bases and pathophysiology of this rare condition.Electronic supplementary materialThe online version of this article (doi:10.1186/s12883-015-0457-3) contains supplementary material, which is available to authorized users.

Detectability of Ischemic Lesions on Diffusion-Weighted Imaging Is Biphasic after Transient Ischemic Attack

Experimental studies of transient focal ischemia indicate biphasic detectability of lesions by diffusion-weighted imaging (DWI); poorly detectable phase exists at 1-12 hours after reperfusion. The present study aimed to clarify whether poorly detectable phase also exists in DWI of transient ischemic attack (TIA) patients. A retrospective study was conducted in 144 consecutive TIA patients who underwent magnetic resonance imaging (MRI) within 2 weeks after carotid TIA. Patients were classified into 9 groups according to time from disappearance of TIA symptoms to DWI: intraischemic period, 0-1 hour, 1-12 hours, 12-24 hours, 1-2 days, 2-3 days, 3-7 days, 7-10 days, and 10-14 days after the end of TIA. Lesions were detected in 33 of 144 patients (22.9%). The frequency of positive lesions was 20% in the intraischemic period and 30.8% at 0-1 hour after the end of TIA; it markedly decreased to 8.7% at 1-12 hours after end of TIA. Thereafter, it increased to 21.7%, 30.8%, 36.4%, 37.0%, 38.5%, and 30% at 12-24 hours, 1-2 days, 2-3 days, 3-7 days, 7-10 days, and 10-14 days after the end of TIA, respectively. In 7 patients, MRI was repeated twice, at 1-12 hours and then at 5-13 days after the end of TIA. Lesions were never detected on the first MRI but were clearly demonstrated in 4 of 7 patients on the second MRI. The detectability of ischemic lesions may be biphasic after TIA as indicated by experimental studies.

Cognitive impairment and whole brain diffusion in patients with carotid artery disease and ipsilateral transient ischemic attack

Objectives: Transient ischemic attack (TIA) with carotid artery disease (CAD) can increase the risk of cognitive decline. However, the neural mechanisms of the disorder remain unclear. The aim of this study was, using diffusion tensor imaging (DTI), to detect microstructural changes in patients with symptomatic CAD presenting with TIA, and to explore their relationship with cognitive functions.Methods: In all, 35 patients with right-sided CAD and ipsilateral TIA and 35 healthy controls were investigated using cognitive tests and voxel-based analysis (VBA) of DTI. The whole brain DTI parameters, fractional anisotropy (FA) and mean diffusivity (MD), were calculate and compared between two groups. A correlation analysis was also performed to explore the relationship between cognitive test scores and whole brain FA and MD values in the patients.Results: We observed two interesting findings. First, compared with the controls, the patients showed significantly increased MD in the right anterior cingulate gyrus (ACG) and decreased FA in the right amygdala. Second, the MD values in the right ACG were negatively correlated with Montreal Cognitive Assessment (MoCA) in the patients.Conclusions: Diffusion tensor imaging parameters are altered in patients with CAD and ipsilateral TIA, which indicates the existence of microstructural abnormalities in the brain of the patients. The significant correlation between DTI abnormalities and cognition reveals the potential of DTI for investigating the pathophysiology mechanism related to the cognitive dysfunction of the disease.

Carotid angioplasty and stenting for symptomatic carotid kinking combined with stenosis

Background Carotid endarterectomy (CEA) is currently the preferred treatment for severe carotid kinking and stenosis. Kinking is generally believed to be a relative contraindication for endovascular stent placement. This article aims to study the necessity, feasibility and security of carotid angioplasty and stenting (CAS) for symptomatic carotid kinking combined with stenosis, and summarize clinical experience of this disease according to therapeutic results. Methods Twenty-two cases with symptomatic carotid kinking and high-grade stenosis demonstrated by digital subtraction angiography (DSA) were performed CAS. Their clinical manifestations, imaging features, procedure safety and follow-up data were collected and retrospectively analyzed. All patients understood CEA and voluntarily received CAS. Results Twenty-two cases with carotid kinking and stenosis were all successfully performed CAS (the success rate was 100%) without stent-related disability or mortality. Twenty-four self-expandable stents were implanted. The mean degree of stenosis was reduced from 85.63% before stenting to 11.25% after stenting and the angles of kinking were improved from 120° (Metz' category). During the period of hospitalization, no transient ischemic attack (TIA) or cerebral infarction occurred, and the clinical symptoms and signs of ischemia, such as dizziness and headache, were improved or disappeared. Besides, no permenant complications or deaths happened. All cases were followed up from 6 to 72 months, among whom 1 patient experienced contralateral carotid TIA, and 2 patients experienced ipsilateral carotid TIA (one indicated aspirin resistance in platelet aggregation test and the other showed restenosis in DSA). Computed tomography angiography (CTA) of 10 patients and Duplex scan of 7 patients during the follow-up demonstrated carotid in good morphology and fluent blood flow, without kinking or restenosis. Conclusion CAS is a feasible and safe therapeutic method and maybe helpful to lower the risk of cerebral ischemia for the patients with symptomatic kinking and stenosis. However, further study is still needed.

Long-term prognosis after transient ischemic attacks.

A retrospective follow-up study of 243 patients with transient ischemic attacks (TIA) is reported. The long-term mortality of the patients was higher than that of the corresponding general population. It is demonstrated that the excess mortality over the whole period of observation, irrespective of the age and sex of the patients, can be characterized by a single figure expressing the slope of the curve obtained by semilogarithmic plotting of the ratios of observed to expected survival against time. The use of this numerical expression--in the present series -0.04--will thus facilitate comparisons of the survival of TIA patients drawn from different populations. Unfavourable prognostic factors were: carotid TIA, associated extracerebral disease, and a history of hypertension. Fatal strokes, being four times as frequent as expected according to published incidence figures, accounted for 20% of the deaths, heart disease 38%. Stroke deaths tended to occur earlier than cardiac deaths. The results support the concept that most TIAs, like strokes, are incidents in the progressive course of a generalized vascular disease. The finding of a constant excess mortality over the years following a TIA makes it difficult to recommend a discontinuation of prophylactic therapy at any particular time.

Distribution and risk factors of steno-occlusive lesions in patients with ischemic cerebrovascular disease

To investigate the distribution of atherosclerotic steno-occlusive lesions in Chinese patients with ischemic cerebrovascular disease and the risk factors for occlusive lesions of intracranial and extracranial arteries. 583 consecutive patients with ischemic cerebrovascular disease, 449 males and 134 females, aged 18-86, 415 with cerebral infarction and 168 with transient ischemic attack (TIA), underwent angiography. The angiographic findings and relevant clinical; data were analyzed. Fifty of the 583 patients had normal findings in angiography and 527 had occlusive lesions of different degrees, among which 24.3% had only extracranial artery disease (EAD), 36.8% had only intracranial disease (IAD), and 38.9% had both EAD and IAD. In total the incidence of IAD was 75.6%, higher than that of EAD (63.2%). In the carotid TIA patients the percentage of IAD was significantly higher than that of the EAD (P = 0.005), and in the cerebral infarction patients the percentage of IAD was higher than that of the EAD, but now significantly. In the patients with TIA of vertebrobasilar artery the incidence of IAD was significantly higher than that of the EAD (P < 0.01). The proportion of pure IAD alone was high in patients aged < or =40 was 75.5% with the middle cerebral artery as the most frequently involved site, while the proportion of coexistence of IAD and EAD was high in the middle-aged and old-aged groups (39.4% and 48.0% respectively, P < 0.001) with the origin of internal carotid artery as the commonest site of lesions. Multivariable Logistic regression identified age, diabetes, hyperlipidemia, and coronary artery disease as the independent risk factors for EAD, and hypertension, diabetes, and hyperlipidemia for IAD. The patients with EAD were significantly elder and had an increased frequency of coronary artery disease compared with those with IAD. In general, the morbidity of IAD was higher that that of EAD in the Chinese patients with ischemic cerebrovascular disease, and presents symptoms of both extracranial and intracranial arteries; however, pure EAD is not uncommon. The distribution pattern of occlusive disease differs among different groups of patients. The patients with EAD are often elder and have an increased frequency of coronary artery disease.

Surgery Insight: carotid endarterectomy—which patients to treat and when?

Over the past 15 years, we have witnessed a resurgence of surgery for prevention of ischemic stroke. Landmark trials including the North American Symptomatic Carotid Endarterectomy Trial and the European Carotid Surgery Trial have explored the role of carotid endarterectomy in this context, comparing the procedure with best medical treatment in patients with high-grade stenosis of the internal carotid artery and transient ischemic attack or minor nondisabling stroke in the same territory. Here, we discuss the lessons learnt from these trials, and review the Asymptomatic Carotid Atherosclerosis Study and the Asymptomatic Carotid Surgery Trial, which attempted to resolve the rather vexing issue of surgical treatment for patients with asymptomatic internal carotid artery stenosis. We also review the best medical treatment for patients undergoing carotid endarterectomy in the perioperative period, and examine the risk of ischemic stroke after CABG surgery, both when this procedure is performed alongside endarterectomy and when CABG surgery and endarterectomy are performed as a two-staged procedure.

Relationship between Detectability of Ischemic Lesions by Diffusion-Weighted Imaging and Embolic Sources in Transient Ischemic Attacks

Background/Aims: The aim of this study is to clarify the relationship between lesion detectability by diffusion-weighted magnetic resonance imaging (DWI) and the etiology of transient ischemic attacks (TIAs). Methods: A retrospective study was performed on 72 patients with carotid TIAs who underwent DWI studies within 2 weeks after the last episode. Results: Lesions were detected in 24 of 72 patients (33%). The detectability of lesions was 12% (3/25) in the large-artery atherosclerosis (LA) group, 57% (8/14) in the cardioembolism (CE) group, 8% (1/13) in the small-artery occlusion (SA) group, and 60% (12/20) in the other etiology or undetermined etiology (UD) group. Detectabilities in the CE group and the UD group were higher than those in the LA and SA groups. Of 24 patients with DWI-positive lesions, 17 (71%) had embolic sources in the heart; 9 were classified in the UD group because they had embolic sources both in the heart and large artery. Conclusion: Ischemic DWI lesions in TIAs are most likely caused by a cardioembolic mechanism. In TIA patients showing lesions on DWI, heart disease should be surveyed as the possible embolic source.

Trombo libre en aurícula izquierda.

An 81 year old woman, diagnosed with rheumatic mitral valve disease and atrial fibrillation ten years previous, was admitted due to a right carotid transient ischemic attack and a acute coronary syndrome. No ST elevation was noted in the region supplied by the anterior descending artery coronary (troponin T increased and anterolateral negative waves T). In recent years years, she had maintained with (anticoagulants) an INR of 2.5-3.5; however, in the previous month the INR had dropped to 1.8. The transthoracic echocardiography showed an anterolateral hypokinesis and a globular hyperechoic mass of 2 x 4 cm which appeared to be a free floating thrombus in the dilated left atrium. This occasionally caused occlusion of the mitral valve, which itself had a severe rheumatic stenosis of approximately 1 cm2. Due to the high risk of occlusion of the mitral valve and systemic embolisms, the mitral valve replacement and thrombectomy was recommend to the patient. The patient refused this treatment and subsequently died 5 days later. This case emphasizes the importance of a suitable level of anticoagulation (INR between 2,5 and 3,5) in patients with mitral stenosis and chronic atrial fibrillation. These cases have a the high risk of thromboembolism, and urgent surgery is mandatory when a free floating left atrial thrombus is observed.

Clinical and operative predictors of outcomes of carotid endarterectomy

The net benefit for patients undergoing carotid endarterectomy is critically dependent on the risk of perioperative stroke and death. Information about risk factors can aid appropriate selection of patients and inform efforts to reduce complication rates. This study identifies the clinical, radiographic, surgical, and anesthesia variables that are independent predictors of deaths and stroke following carotid endarterectomy. A retrospective cohort study of patients undergoing carotid endarterectomy in 1997 and 1998 by 64 surgeons in 6 hospitals was performed (N = 1972). Detailed information on clinical, radiographic, surgical, anesthesia, and medical management variables and deaths or strokes within 30 days of surgery were abstracted from inpatient and outpatient records. Multivariate logistic regression models identified independent clinical characteristics and operative techniques associated with risk-adjusted rates of combined death and nonfatal stroke as well as all strokes. Death or stroke occurred in 2.28% of patients without carotid symptoms, 2.93% of those with carotid transient ischemic attacks, and 7.11% of those with strokes (P < .0001). Three clinical factors increased the risk-adjusted odds of complications: stroke as the indication for surgery (odds ratio [OR], 2.84; 95% confidence interval [CI] = 1.55-5.20), presence of active coronary artery disease (OR, 3.58; 95% CI = 1.53-8.36), and contralateral carotid stenosis > or =50% (OR, 2.32; 95% CI = 1.33-4.02). Two surgical techniques reduced the risk-adjusted odds of death or stroke: use of local anesthesia (OR, 0.30; 95% CI = 0.16-0.58) and patch closure (OR, 0.43; 95% CI = 0.24-0.76). Information about these risk factors may help physicians weigh the risks and benefits of carotid endarterectomy in individual patients. Two operative techniques (use of local anesthesia and patch closure) may lower the risk of death or stroke.

Fibromuscular Dysplasia of the Carotid Artery: Diagnosis with Duplex Ultrasonography

Purpose The diagnosis of carotid artery fibromuscular dysplasia is usually made with conventional angiography performed to evaluate a suspected carotid stenosis. The ultrasound findings with fibromuscular dysplasia have not been well described. This study was performed to assess the characteristics of carotid artery fibromuscular dysplasia with duplex ultrasonography. Methods The hospital records for all patients who had carotid duplex ultrasonography were reviewed from January 2000 to October 2003. Patients with findings suspicious for fibromuscular dysplasia formed the basis of this study. The patient demographics, their presenting symptoms, and ultrasound findings were analyzed. Results Carotid duplex studies were performed on 9157 patients during the study period. The presumptive diagnosis of fibromuscular dysplasia was made in 13 female patients (1.2%), with a mean age of 67 ± 10 years (range, 52-79 years). Patients were referred for asymptomatic carotid bruits ( n = 10, 77%) or transient ischemic attack ( n = 3, 23%). Both mid and distal internal carotid artery involvement were seen in five patients (38%), whereas eight patients (62%) had disease isolated to the distal internal carotid artery. Bilateral carotid artery involvement occurred in eight patients (62%). A consistent finding in all patients was multiple areas of alternating focal thickening with thin, dilated arterial walls. Other sonographic findings included velocity increases (mean, 181 cm/sec; range, 135-318 cm/sec), color flow disturbance, and scarcity of plaque in the suspected arterial segment. Magnetic resonance angiography or carotid angiography was performed on seven (54%) patients, confirming the ultrasound diagnoses. One symptomatic patient was successfully treated with open graduated endoluminal dilatation. One patient with asymptomatic carotid bruit underwent carotid stent placement for rapid progression of the disease. No disease progression was seen on follow-up duplex examination in the remaining group, and no patient became symptomatic. Conclusions Fibromuscular dysplasia should be suspected in female patients with high-grade mid to distal carotid artery stenosis without significant atherosclerotic disease. This study demonstrates the usefulness of duplex ultrasound as both a screening test and diagnostic examination for carotid artery fibromuscular dysplasia. Follow-up is warranted in these patients.

Use of Magnetic Resonance Imaging in Predicting Further Vascular Events Among Patients With Transient Ischemic Attacks

To the Editor: In the October 2004 issue of Stroke , Purroy et al reported a higher risk of further vascular events among transient ischemic attack (TIA) patients with diffusion-weighted imaging (DWI) acute ischemic lesions.1 They prospectively studied 83 patients with TIA and suggested that duration of symptoms (>60 minutes), presence of DWI acute ischemic lesion, and large vessels disease were important risk factors for the recurrence of vascular events, including cerebrovascular ones. However, only a minority (9.6%) of patients had their magnetic resonance imaging performed (MRI) within 2 days of symptom onset.1 As quoted by the authors, 10.5% of patients with TIA will have a stroke within the next 90 days of their TIA, and 25% to 50% of these have their stroke within the first 24 to 48 hours.2,3 Therefore, a substantial portion of MRI data may show a second cerebrovascular ischemic event instead of the first stroke/TIA and subsequently do not predict the primary outcome. We would like to know the proportion of clinically defined early/late new vascular events. Second, the inclusion of TIA as a primary endpoint is problematic and not conventional in relation to stroke prevention trials.4–8 The percentage of patients with TIA versus stroke at outcome should be stated. Third, a significant proportion of patients presented with vertebrobasilar (43.4%) TIA. What symptoms were accepted as diagnosis of vertebrobasilar TIA? Isolated “dizziness” of unclear origin, for example, is sometimes diagnosed as possible vertebrobasilar TIA but has multiple alternate differential diagnoses that may not ever be conclusively determined. It would have been interesting to know the proportion of vertebrobasilar and carotid TIA among patients with DWI acute ischemic lesions and further vascular events. Fourth, …

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Revisiting the appropriateness of carotid endarterectomy.

In the 1980s, carotid endarterectomy was controversial because proof of efficacy was lacking, complication rates were high, and one third of cases were reported to be inappropriate. Since publication of several randomized controlled trials (RCTs), rates of carotid endarterectomy have doubled nationwide. This study assesses the appropriateness and use of carotid endarterectomy since publication of the RCTs. Using the literature, we developed a list of 1557 mutually exclusive indications for carotid endarterectomy and asked a panel of national experts to rate the appropriateness of each indication using the RAND methodology. We used these ratings to assess appropriateness in a sample of 2124 patients who underwent the procedure in 1997 to 1998 in 6 hospitals. We also analyzed the reasons for the procedure and rates of death, stroke, and myocardial infarction within 30 days of surgery. Overall, 84.9% of operations were done for appropriate reasons, 4.5% for uncertain reasons, and 10.6% for inappropriate reasons. Among procedures considered inappropriate, the most common reasons were high comorbidity (46.6%) and minimal stenosis (27.1%). Overall, 72.5% were asymptomatic, 17.4% had a carotid transient ischemic attack, and 10.1% had a stroke. The 30-day rate of death or stroke was 5.47% for symptomatic patients and 2.26% for asymptomatic patients. Among patients having combined carotid and coronary artery bypass graft surgery, the rate was 10.32%. The complication rate in asymptomatic patients with high comorbidity was 5.56%. Since the RCTs, rates of overuse appear to have fallen considerably, although they are still significant. A major shift has occurred toward operating on asymptomatic patients. Although overall complication rates were low, rates among asymptomatic patients with high comorbidity exceeded recommended thresholds.

Isolated petrous carotid stenosis and transient ischemic attack.

Although anterior circulation transient ischemic attacks (TIAs) tend to be more common in patients with extra- cranial carotid arterial disease than in those with intracranial carotid or middle cerebral arterial disease, the authors recently encountered 4 patients with both recurrent, stereotypical TIAs as well as isolated stenosis of their petrous internal carotid artery (ICA). While the gold standard for establishing the diagnosis of intracranial large-artery disease has always been conventional angiography, magnetic resonance angiography changes, confirmed with intra-arterial digital subtraction angiography in 2 of these patients, were quite sufficient to define the occlusive disease in each of the cases. Petrous ICA stenosis is not uncommon, but it has often been overshadowed by the search for extracranial ICA disease that might be amenable to surgical reconstruction.