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Background and PurposeThe absence of acute ischemic lesions in diffusion-weighted imaging (DWI) in transient ischemic attack (TIA) patients makes it difficult to diagnose the true vascular etiologies. Among patients with DWI-negative TIA, we investigated whether the presence of a perfusion-weighted imaging (PWI) abnormality implied a true vascular event by identifying new acute ischemic lesions in follow-up magnetic resonance imaging (MRI) in areas corresponding to the initial PWI abnormality.MethodsThe included patients underwent DWI and PWI within 72 hours of TIA and also follow-up DWI at 3 days after the initial MRI. These patients had visited the emergency room between July 2009 and May 2015. Patients who demonstrated initial DWI lesions were excluded. The initial PWI abnormalities in the corresponding vascular territory were visually classified into three patterns: no abnormality, focal abnormality, and territorial abnormality.ResultsNo DWI lesions were evident in initial MRI in 345 of the 443 TIA patients. Follow-up DWI was applied to 87 of these 345 DWI-negative TIA patients. Initial PWI abnormalities were significantly associated with follow-up DWI abnormalities: 8 of 43 patients with no PWI abnormalities (18.6%) had new ischemic lesions, whereas 13 of 16 patients with focal perfusion abnormalities (81.2%) had new ischemic lesions in the areas of initial PWI abnormalities [odds ratio (OR)=15.1, 95% confidence interval (CI)=3.6–62.9], and 14 of 28 patients with territorial perfusion abnormalities (50%) had new lesions (OR=3.7, 95% CI=1.2–11.5).ConclusionsPWI is useful in defining whether or not the transient neurological symptoms in DWI-negative TIA are true vascular events, and will help to improve the understanding of the pathomechanism of TIA.

It is essential to identify high risk transient ischemic attack (TIA) patients. The previous study reported that the CSR (comprehensive stroke recurrence) model, a neuroimaging model, had a high predictive ability of recurrent stroke. The aims of this study were to validate the predictive value of CSR model in TIA patients and compare the predictive ability with ABCD3-I score. Data were analyzed from the prospective hospital-based database of patients with TIA which defined by the World Health Organization time-based criteria. The predictive outcome was stroke occurrence at 90 days. The receiver-operating characteristic (ROC) curves were plotted and the C statistics were calculated as a measure of predictive ability. Among 1186 eligible patients, the mean age was 57.28 ± 12.17 years, and 474 (40.0%) patients had positive diffusion-weighted imaging (DWI). There were 118 (9.9%) patients who had stroke within 90 days. In 1186 TIA patients, The C statistic of CSR model (0.754; 95% confidence interval [CI] 0.729–0.778) was similar with that of ABCD3-I score (0.717; 95% CI 0.691–0.743; Z = 1.400; P = 0.1616). In 474 TIA patients with positive DWI, C statistic of CSR model (0.725; 95% CI 0.683–0.765) was statistically higher than that of ABCD3-I score (0.626; 95% CI 0.581–0.670; Z = 2.294; P = 0.0245). The CSR model had good predictive value for assessing stroke risk after TIA, and it had a higher predictive value than ABCD3-I score for assessing stroke risk for TIA patients with positive DWI.

Transient Ischemic Attacks—Populations and Prognosis

Evaluation of risk factors for stroke/embolism and of complications due to anticoagulant therapy in atrial fibrillation.

Clinical Characteristics Associated with Abnormal Diffusion-Weighted Images in Patients with Transient Cerebral Ischemic Attack

The evaluation of headache in patients with transient ischemic attacks (TIA) has various sources of difficulty, the definition of TIA being the most relevant. The classical definition needs to be supplemented with a normal CT scan if a misleading diagnostic statement is to be avoided. The clinical features of 90 patients suffering from TIA and who had contrast-enhanced CT scans are reported. Headache occurred in 30% of the patients. Headache prevailed in patients with vertebrobasilar TIA compared with carotid TIA (p less than 0.05). Headache prevailed as a preceding (24 h) and/or concomitant sign compared with other neurological symptoms (77.8% of the patients). Headache was ipsilateral, in the anterior half of the head in the carotid TIA and in the posterior half of the head in the vertebrobasilar TIA. In about 50% of the patients generalized non-localized headache occurred. Headache usually preceded the neurological symptoms in cases of arterial occlusion (20 carotid, 3 vertebral artery), usually appearing during or after the attack in cases without arterial occlusion. Only 2 cases out of 20 with positive CT scan had headache. These two patients suffered from a rather large hypodense lesion. The other 18 patients showed lacunar lesions. Different hypotheses concerning the physiopathology of the headache associated with TIA are discussed.

BackgroundPatients with transient ischemic attack (TIA) have an increased risk of vascular events. There is scarce data regarding the prognosis of patients with transient neurological symptoms less typical of TIA, in whom a vascular origin cannot be excluded, also known as possible TIA. In this study we aimed to compare the short-term prognosis between TIA and Possible TIA patients.MethodsPatients with transient neurological events consecutively referred to a TIA Clinic during five years were classified as TIA, Possible TIA or mimic. Patients were prospectively followed. We compared the outcome at 30 and 90 days after TIA or Possible TIA. The primary outcome was stroke and the secondary outcome was a combination of vascular events (stroke, TIA, myocardial infarction or vascular death).ResultsTwo hundred and fifty eight TIA and 109 Possible TIA patients were included. Possible TIA patients had no stroke 30 and 90 days after the event. In contrast, 3.1 % and 4 % of TIA patients had stroke at the same time points. Combined vascular events occurred in 1.9 % of Possible TIA (myocardial infarction) and 9.8 % of TIA patients (stroke and TIA) after 30 days (OR = 0.18, 95 % CI 0.04 to 0.76, P = 0.02); and in 1.9 % of Possible TIA patients (myocardial infarction) and 11.3 % of TIA patients (stroke and TIA) after 90 days (OR = 0.16, 95 % CI 0.04 to 0.67, P = 0.012).ConclusionsIn this exploratory study, Possible TIA patients had less short-term vascular events than TIA patients.

The burden of stroke to the health care system in the United States continues to increase. Stroke-related hospital admissions grew from 580 000 in 1988 to 820 000 in 1997, an 18.6% increase after age adjustment.1 More effective stroke prevention provides the primary means of reducing these alarming statistics. This can be accomplished through better implementation of known preventive strategies2 and through research into new approaches to stroke prevention. Diet can affect stroke risk, with epidemiological studies indicating an inverse relationship between fruit and vegetable consumption and cardiovascular events.2 For example, one study including individuals free of cardiovascular disease at baseline found that the relative risk (RR) of stroke was reduced by 31% (RR, 0.69; 95% CI, 0.52 to 0.92) for persons in the highest quintile of fruit and vegetable intake.3 Analysis of data from the National Health and Nutrition Examination Survey (NHANES) Epidemiologic Follow-up Study supports these results.4 The study included 9608 adults aged 25 to 74 years who were free of cardiovascular disease at a baseline evaluation between 1971 and 1975. Consumption of fruits and vegetables ≥3 times per day compared with <1 time per day was associated with a 27% lower stroke incidence (RR, 0.73; 95% CI, 0.57 to 0.95) after adjustment for potential confounders, suggesting the benefit is not attributable to a healthy-user effect. The results reinforce present recommendations for an intake of 5 servings of fruits and vegetables daily. Because fruits and vegetables contain antioxidants, antioxidant food supplements might be expected to have similar benefits. However, a 3-year study of patients with coronary heart disease, low levels of high-density lipoprotein cholesterol, and normal levels of low-density lipoprotein cholesterol found no reduction in cardiovascular end points (death, myocardial infarction, stroke, and revascularization procedures) with the use of antioxidant supplements (800 IU …

The clinical diagnosis of transient ischemic attack is highly subjective, and the risk prediction after transient ischemic attack using the clinical parameters still remains unsatisfactory. We aimed to investigate the diagnostic and prognostic value of multimodal magnetic resonance imaging in transient ischemic attack patients. We prospectively performed diffusion-weighted imaging, perfusion-weighted imaging, and intracranial and extracranial magnetic resonance angiogram within 72 h of symptom onset in 162 transient ischemic attack patients defined by the classical time-based definition. Follow-up diffusion-weighted imaging was obtained three-days later in patients who did not exhibit lesions on the initial diffusion-weighted imaging. The occurrence of clinical events (transient ischemic attack or stroke) three-months after the initial transient ischemic attack was recorded, and the ABCD2 and ABCD3-I scores were calculated. The clinical and imaging parameters were compared between patients with and without initial diffusion-weighted imaging lesion, clinical events, and follow-up diffusion-weighted imaging lesions. Abnormalities were present on diffusion-weighted imaging, perfusion-weighted imaging, and magnetic resonance angiogram in 38·9%, 44·1%, and 51·9% of patients, respectively. Diffusion-weighted imaging plus perfusion-weighted imaging explained 64·8%, and the addition of magnetic resonance angiogram explained 74% of the transient ischemic attack symptoms. The initial diffusion-weighted imaging positivity was associated with longer time from symptom onset to magnetic resonance imaging examination (odds ratio, 1·039; 95% confidence interval, 1·008-1·071; P=0·013). On follow-up diffusion-weighted imaging, new lesions were found in 46·7% of the patients who initially showed normal diffusion-weighted imaging findings. Initial perfusion-weighted imaging abnormality predicted the appearance of follow-up diffusion-weighted imaging lesion (chi-square=7·774, P=0·005). During the three-months follow-up, 23 patients (14·2%) experienced subsequent transient ischemic attack (n=16) or stroke (n=7). Symptomatic magnetic resonance angiogram abnormality (odds ratio, 12·667; 95% confidence interval, 2·859-56·110; P=0·001) was the only independent factor associated with clinical events with a sensitivity of 91·3% and specificity of 54·7% (C statistics, 0·73). None with initially normal multimodal magnetic resonance imaging findings developed subsequent clinical events. Approximately three-quarter of transient ischemic attack is associated with multimodal magnetic resonance imaging abnormality. Initial perfusion-weighted imaging abnormality predicts newly developed diffusion-weighted imaging lesions, and symptomatic magnetic resonance angiogram abnormality seems to be the most important predictor for subsequent clinical events. Multimodal magnetic resonance imaging appears to be useful in assessing transient ischemic attack and predicting outcome in these patients.

The documented annual risk of ischemic cardiac, cerebral and other vascular events in patients with carotid stenosis depends upon the population studied, in addition to other established risk factors. The control groups included in medical or surgical trials are selected populations and are usually found to have lower event rates than the total cohort. Community studies indicate that, in patients with asymptomatic carotid disease, the annual stroke rate is about 1–2%, and that the death rate (usually due to cardiac causes) is 4–5%. Among the many factors influencing outcome, the severity of carotid stenosis is probably the most dominant. Patients with carotid stenoses of &lt; 75% have annual stroke rates of 1–2%, while those with carotid stenoses of &gt; 75 % have annual stroke rates of 5–6%, with a proportionately increased death rate. When symptomatic and asymptomatic groups are compared and matched for age and sex, a higher prevalence of carotid stenosis is found in stroke patients than in transient ischemic attack (TIA) patients; both stroke and TIA patients have more frequent and more severe carotid stenosis than asymptomatic patients. In patients with TIA and stroke, the evaluation of vascular risks also depends on the conditions under which the population has been studied. Community studies, especially those with prospective follow-up, such as the Mayo Clinic series, allow a more generalized perspective. In patients with TIA, the annual incidence of stroke is approximately 5–7%, and the annual death rate is approximately 7%. In patients with completed ischemic stroke, the annual rate of recurrent stroke is 10%, and the annual death rate is approximately 7%. The vascular outcome depends on a variety of factors. Morbidity and mortality are lower after vertebrobasilar strokes than after carotid strokes; outcome is also affected by clinical factors, such as age, and the presence of concomitant stroke risk factors, such as hypertension. In all forms of cerebrovascular disease, both symptomatic and asymptomatic the incidence of myocardial infarction and cardiac death is 4–5 times higher than the-incidence of stroke.

Objectives: Patients with transient ischemic attack (TIA) are at high risk of early stroke, indicating a need for urgent diagnostic workup and treatment. Atrial fibrillation (AF) is one of important causes for TIA. The purpose of this study was to investigate characteristics of TIA patients with AF, using data of a multicenter retrospective study. Methods: The subjects of this study were TIA patients admitted to 13 stroke centers within 7 days after onset between 2008 and 2009. The definition of TIA used in this study was that of clinical symptoms lasting less than 24 hours, regardless of imaging findings. We compared baseline characteristics and diffusion weighted-MRI (DWI) findings between patients with AF and those without AF. Results: A total of 464 patients (69 ± 13 years in age, 172 women) were enrolled. We diagnosed 79 patients (17%) as having AF. TIA patients with AF were older (74 ± 9 vs. 67 ± 14 years old, P = 0.0001) and more likely to have a longer length of hospital stay (15 ± 9 vs. 14 ± 20 days, P = 0.046) than those without AF. Of 464 TIA patients, 458 patients (99%) underwent head MRI. DWI lesion was detected in 96 (21%) patients. There was no difference of DWI positivity rate between patients with or without AF (28% vs. 20%, P = 0.10). Compared to patients without AF, patients with AF were more likely to have a single lesion on DWI (86% vs. 51%, P = 0.005). DWI lesion of ≥15 mm was found more frequently in TIA patients with AF than in those without AF (45% vs. 22%, P = 0.04). Conclusions: This study demonstrated that TIA patients with AF were older and had a longer length of hospital stay than those without AF. In addition, characteristics of DWI findings differed between TIA patient with AF and those without AF; TIA patients with AF were more likely to have a single lesion with a size of ≥15 mm.

Objective To investigate the relationship between enlarged perivascular space (EPVS) and retinal vessel abnormalities in transient ischemic attack (TIA) and mild stroke patients. Methods TIA and mild cerebral infarction (National Institutes of Health Stroke Scale score≤3) patients were enrolled from March to August 2019 in Changzhou Second People′s Hospital. Magnetic resonance imaging and retinal fundus photography were performed in all patients. Retinal arteriovenous diameter was semi-automatically measured, and retinal arteriosclerosis grades, vascular curvature, hemorrhages, microangioma, hard exudation, soft exudation, arteriovenous nicking and venous beads were assessed. Patients were divided into two groups according to the existence of EPVS: EPVS group and non-EPVS group. The baseline data of the two groups were compared and further multivariate Logistic regression was carried out. After normal transformation of the number of EPVS, the correlation between the grades of EPVS and converted EPVS was analyzed. The relationship between the number of converted EPVS and the grades and retinal fundus vascular lesions was further analyzed. Results A total of 123 patients were included, including 99 patients with cerebral infarction, 24 patients with TIA; 52 patients without EPVS and 71 patients with EPVS. The EPVS group was more than the non-EPVS group in age ((68.61±12.71) years and (63.37±13.53) years, t=-2.198, P=0.030), history of hypertension (52 (73.2%) and 25 (48.1%), χ2=8.118, P=0.004), hemangioma (17 (23.9%) and 5 (9.6%), χ2=4.196, P=0.041), arteriovenous nicking (50 (70.4%) and 8 (15.4%), χ2=36.488, P<0.05) and arteriosclerosis grades (1 (1, 2) and 0 (0, 1), Z=-7.454, P<0.05), and less than the non-EPVS group in central retinal artery equivalent (CRAE; (106.31±15.02) mm and (113.89±11.86) mm, t=3.014, P=0.003) and arteriole-to-venule ratio (AVR; 0.54±0.07 and 0.59±0.05, t=4.553, P<0.05). Multivariate Logistic regression analysis showed arteriosclerosis grades (OR=7.781, 95%CI 2.876-21.055, P<0.05) and hypertension (OR=3.203, 95%CI 1.049-9.777, P=0.041) were related factors for EPVS. Adjusting for age, sex, hypertension and diabetes, the normally transformed EPVS was found positively correlated with arteriovenous nicking (B=0.556, 95%CI 0.203-0.910, P=0.003) and arteriosclerosis grade (B=0.417, 95%CI 0.259-0.576, P<0.05), and negatively correlated with AVR (B=-4.213, 95%CI-6.712--1.714, P=0.001). The grades of EPVS were positively correlated with arteriosclerosis (r=0.764, P<0.05), and negatively correlated with CRAE (r=-0.287, P<0.05) and AVR (r=-0.422, P<0.05). Conclusions Hypertension and retinal arteriosclerosis are related factors of EPVS in mild stroke and TIA patients. EPVS is correlated with retinal vessel abnormalities. The more serious of EPVS is, the more serious of retinal arteriosclerosis is, the higher ratio of arteriovenous nicking is, the smaller of CRAE and AVR are. Key words: Perivascular space; Retina; Microvessels; Brain infarction; Fundus oculi; Arteriosclerosis

Recent prospective registration studies of transient ischemic attack in Western countries demonstrated that large artery atherosclerosis is the highest risk etiology for early stroke recurrence under urgent evaluation and treatment. On the other hand, some limited transient ischemic attack studies from East Asian countries showed transient ischemic attack patients due to small vessel occlusion were at a higher early stroke risk. We aimed to assess the risk for early stroke in small vessel occlusion-transient ischemic attack patients in a Japanese large transient ischemic attack registry. We analyzed the data of a prospective Japanese transient ischemic attack registry including 1320 transient ischemic attack patients within seven days after onset. Small vessel occlusion-transient ischemic attack was defined as the presence of lacunar transient ischemic attack syndrome, without other etiologies. The outcome measure was recurrent stroke within 30 days after transient ischemic attack. The predictors of 30-day recurrent stroke were estimated using the Cox proportional hazards model. The study population had a mean age of 69 ± 12 years and 470 were women. Recurrent stroke was observed in 61 patients (4.6%), and the highest rate was observed with small vessel occlusion-transient ischemic attack (7.8%), followed by large artery atherosclerosis (5.4%). In multivariate analysis, recurrent stroke was independently associated with small vessel occlusion-transient ischemic attack (hazard ratio (HR): 2.01, 95% confidence interval (CI): 1.19-3.35), higher systolic blood pressure (HR: 1.18, 95% CI: 1.08-1.28), and presentation within 3 h after onset (HR: 2.21, 95% CI: 1.27-4.04). Furthermore, small vessel occlusion-transient ischemic attack with acute small deep infarct on diffusion-weighted imaging was a stronger predictor of recurrent stroke (HR: 4.87, 95% CI: 2.09-10.0). Small vessel occlusion-transient ischemic attack, especially with acute small deep infarct, had a higher early stroke risk compared with other etiologies in Japanese transient ischemic attack patients who received early management.

Association of perfusion variables with functional outcome in acute mild ischemic stroke patients or transient ischemic attack

Clinical management of patients with acute stroke and the approach used for secondary prevention depends upon clarification of pathogenesis. Although most strokes are a consequence of cerebrovascular disease, ≈15% to 20% of ischemic (nonhemorrhagic) strokes have been attributed to cardiogenic embolism.1 In practice, determination of the stroke mechanism is fraught with uncertainty, particularly when the possibility of thromboembolism emanating from atherosclerotic lesions in the aorta or cervical arteries is considered. When cardiogenic embolism is suspected, cardiac ultrasound is the principal method used to identify the potential source. The finding of left atrial enlargement has been shown to bear a significant relationship to the risk of stroke in a multivariate analysis of population-based data from the Framingham Heart Study2. The most frequent confounding variable is atrial fibrillation, occurring in >2 million patients in North America and in over half of all patients with cardiogenic embolism. Criteria for selection of patients with acute ischemic stroke for transesophageal echocardiography (TEE) to search for a potential cardiac source of embolism are controversial, particularly because cardiogenic embolism is often an uncertain diagnosis that is inferred merely on the basis of the finding of potential cardiac source. Even after extensive investigation, ≈40% of ischemic stroke patients have no clearly identifiable pathogenesis (cryptogenic stroke).3 In one study, 62% of patients younger than 60 years of age without an obvious source of cerebral infarction and 23% of those with arterial lesions had potential sources of cardiogenic embolism identified by TEE ( P =0.0007 for the difference).4 See p 2625 Among the cardiac anomalies detected by TEE that have been implicated as risk factors for stroke are patent foramen ovale (PFO) and atrial septal aneurysm (ASA).5,6⇓ The foramen ovale, a remnant of the fetal circulation, remains patent through adulthood in ≈1 in 4 …