National study on emergency department visits for transient ischemic attack, 1992-2001

Care settings of transient ischemic attack in the United States: A cohort study from the TriNetX health research network

BACKGROUND

Evaluation and hospitalization rates after a transient ischemic attack (TIA)-like presentation vary widely in clinical practice. This study aimed to examine variations in care settings at initial TIA diagnosis in the United States.

METHODS

We retrospectively analyzed an adult cohort with a first TIA principal diagnosis between January 1, 2015, and December 31, 2019, from TriNetX Diamond Network. Care settings at TIA diagnosis were defined as hospital care (including inpatient services and observation unit care without admission) and outpatient care (including any outpatient or emergency department visits). We estimated the distribution of care settings at TIA diagnosis and examined the associations of the hospital care setting with baseline age, sex, race, ethnicity, region, and stroke history.

RESULTS

Among the 554,315 included patients, 38.8% received hospital care at their initial TIA diagnosis. A higher percentage of hospital care was observed in the age group of 50-64 years (40.3%), Black (46.0%), Hispanic (41.2%), South (40.9%), and Midwest (43.0%) Regions, and with a history of stroke (39.6%). Multivariable logistic regression consistently showed patients who were aged 50-64 years (Odds Ratio=1.09, 95% CI: [1.07, 1.11]), Black (1.28, [1.24, 1.32]), Hispanic (1.13, [1.09, 1.18]), from South (1.20, [1.18, 1.22]) and Midwest Region (1.33, [1.30, 1.35]), and had a history of stroke (1.02, [1.00, 1.04]) to more likely receive hospital care.

CONCLUSIONS

Although there are TIA care disparities based on demographics, most patients with initial TIA received acute care in outpatient settings. It is imperative to ensure primary providers can risk-stratify TIA patients and provide rapid and proper management.

Recognizing Posterior Circulation Transient Ischemic Attacks Presenting as Episodic Isolated Dizziness

Diagnosing patients presenting to the emergency department with self-limited episodes of isolated dizziness (the episodic vestibular syndrome) requires a broad differential diagnosis that includes posterior circulation transient ischemic attack. Because these patients are, by definition, asymptomatic without new neurologic findings on examination, the diagnosis, largely based on history and epidemiologic context, can be challenging. We review literature that addresses the frequency of posterior circulation transient ischemic attack in this group of patients compared with other potential causes of episodic vestibular syndrome. We present ways of distinguishing posterior circulation transient ischemic attack from vestibular migraine, the most common cause of episodic vestibular syndrome. We also present a diagnostic algorithm that may help clinicians to work their way through the differential diagnosis.

Safety and Feasibility of an Emergency Department-to-Outpatient Pathway for Patients With TIA and Nondisabling Stroke

Background and Objectives

Evaluation of transient ischemic attack/nondisabling ischemic strokes (TIA/NDS) in the emergency department (ED) contributes to capacity issues and increasing health care expenditures, especially high-cost duplicative imaging.

Methods

As an institutional quality improvement project, we developed a novel pathway to evaluate patients with TIA/NDS in the ED using a core set of laboratory tests and CT-based neuroimaging. Patients identified as 'low risk' through a safety checklist were discharged and scheduled for prompt outpatient tests and stroke clinic follow-up. In this prespecified analysis designed to assess feasibility and safety, we abstracted data from patients consecutively enrolled in the first 6 months.

Results

We compared data from 106 patients with TIA/NDS enrolled in the new pathway from April through September 2020 (age 67.9 years, 45% female), against 55 unmatched historical controls with TIA encountered from April 2016 through March 2017 (age 68.3 years, 47% female). Both groups had similar median NIHSS scores (pathway and control 0) and ABCD2 scores (pathway and control 3). Pathway-enrolled patients had a 44% decrease in mean ED length of stay (pathway 13.7 hours, control 24.4 hours, p < 0.001) and decreased utilization of ED MRI-based imaging (pathway 63%, control 91%, p < 0.001) and duplicative ED CT plus MRI-based brain and/or vascular imaging (pathway 35%, control 53%, p = 0.04). Among pathway-enrolled patients, 89% were evaluated in our stroke clinic within a median of 5 business days; only 5.5% were lost to follow-up. Both groups had similar 90-day rates of ED revisits (pathway 21%, control 18%, p = 0.84) and recurrent TIA/ischemic stroke (pathway 1%, control 2%, p = 1.0). Recurrent ischemic events among pathway-enrolled patients were attributed to errors in following the safety checklist before discharge.

Discussion

Our TIA/NDS pathway, implemented during the initial outbreak of COVID-19, seems feasible and safe, with significant positive impact on ED throughput and ED-based high-cost duplicative imaging. The safety checklist and option of virtual telehealth follow-up are novel features. Broader adoption of such pathways has important implications for value-based health care.

Risk of Subsequent Stroke Among Patients Receiving Outpatient vs Inpatient Care for Transient Ischemic Attack: A Systematic Review and Meta-analysis

IMPORTANCE

Transient ischemic attack (TIA) often indicates a high risk of subsequent cerebral ischemic events. Timely preventive measures improve the outcome.

OBJECTIVE

To estimate and compare the risk of subsequent ischemic stroke among patients with TIA or minor ischemic stroke (mIS) by care setting.

DATA SOURCES

MEDLINE, Web of Science, Scopus, Embase, International Clinical Trials Registry Platform, ClinicalTrials.gov, Trip Medical Database, CINAHL, and all Evidence-Based Medicine review series were searched from the inception of each database until October 1, 2020.

STUDY SELECTION

Studies evaluating the occurrence of ischemic stroke after TIA or mIS were included. Cohorts without data on evaluation time for reporting subsequent stroke, with retrospective diagnosis of the index event after stroke occurrence, and with a report of outcomes that were not limited to patients with TIA or mIS were excluded. Two authors independently screened the titles and abstracts and provided the list of candidate studies for full-text review; discrepancies and disagreements in all steps of the review were addressed by input from a third reviewer.

DATA EXTRACTION AND SYNTHESIS

The study was prepared and reported following the Preferred Reporting Items for Systematic Reviews and Meta-analyses, Meta-analysis of Observational Studies in Epidemiology, Methodological Expectations of Cochrane Intervention Reviews, and Enhancing the Quality and Transparency of Health Research guidelines. The Risk of Bias in Nonrandomized Studies-of Exposures (ROBINS-E) tool was used for critical appraisal of cohorts, and funnel plots, Begg-Mazumdar rank correlation, Kendall τ2, and the Egger bias test were used for evaluating the publication bias. All meta-analyses were conducted under random-effects models.

MAIN OUTCOMES AND MEASURES

Risk of subsequent ischemic stroke among patients with TIA or mIS who received care at rapid-access TIA or neurology clinics, inpatient units, emergency departments (EDs), and unspecified or multiple settings within 4 evaluation intervals (ie, 2, 7, 30, and 90 days).

RESULTS

The analysis included 226 683 patients from 71 articles recruited between 1981 and 2018; 5636 patients received care at TIA clinics (mean [SD] age, 65.7 [3.9] years; 2291 of 4513 [50.8%] men), 130 139 as inpatients (mean [SD] age, 78.3 [4.0] years; 49 458 of 128 745 [38.4%] men), 3605 at EDs (mean [SD] age, 68.9 [3.9] years; 1596 of 3046 [52.4%] men), and 87 303 patients received care in an unspecified setting (mean [SD] age, 70.8 [3.8] years, 43 495 of 87 303 [49.8%] men). Among the patients who were treated at a TIA clinic, the risk of subsequent stroke following a TIA or mIS was 0.3% (95% CI, 0.0%-1.2%) within 2 days, 1.0% (95% CI, 0.3%-2.0%) within 7 days, 1.3% (95% CI, 0.4%-2.6%) within 30 days, and 2.1% (95% CI, 1.4%-2.8%) within 90 days. Among the patients who were treated as inpatients, the risk of subsequent stroke was to 0.5% (95% CI, 0.1%-1.1%) within 2 days, 1.2% (95% CI, 0.4%-2.2%) within 7 days, 1.6% (95% CI, 0.6%-3.1%) within 30 days, and 2.8% (95% CI, 2.1%-3.5%) within 90 days. The risk of stroke among patients treated at TIA clinics was not significantly different from those hospitalized. Compared with the inpatient cohort, TIA clinic patients were younger and had had lower ABCD2 (age, blood pressure, clinical features, duration of TIA, diabetes) scores (inpatients with ABCD2 score >3, 1101 of 1806 [61.0%]; TIA clinic patients with ABCD2 score >3, 1933 of 3703 [52.2%]).

CONCLUSIONS AND RELEVANCE

In this systematic review and meta-analysis, the risk of subsequent stroke among patients who were evaluated in a TIA clinic was not higher than those hospitalized. Patients who received treatment in EDs without further follow-up had a higher risk of subsequent stroke. These findings suggest that TIA clinics can be an effective component of the TIA care component pathway.

Risk of Ischemic Stroke after an Inpatient Hospitalization for Transient Ischemic Attack in the United States

INTRODUCTION

A diagnosis of transient ischemic attack (TIA) must be followed by prompt investigation and rapid initiation of measures to prevent stroke. Prior studies evaluating the risk of stroke after TIA were conducted in the emergency room or clinic settings. Experience of patients admitted to the hospital after a TIA is not well known. We sought to assess the early risk of ischemic stroke after inpatient hospitalization for TIA.

METHODS

We used the 2010-2015 Nationwide Readmissions Database to identify all hospitalizations with the primary discharge diagnosis of TIA and investigated the incidence of ischemic stroke readmissions within 90 days of discharge from the index hospitalization.

RESULTS

Of 639,569 index TIA admissions discharged alive (mean ± SD age 70.4 ± 14.4 years, 58.7% female), 9,131 (1.4%) were readmitted due to ischemic stroke within 90 days. Male sex, head/neck vessel atherosclerosis, hypertension, diabetes, atrial flutter/fibrillation, previous history of TIA/stroke, illicit drug use, and higher Charlson Comorbidity Index score were independently associated with readmissions due to ischemic stroke. Ischemic stroke readmissions were associated with excess mortality, discharge disposition other than to home, and elevated cost.

CONCLUSIONS

Patients hospitalized for TIA have a lower risk of ischemic stroke compared to that reported in the studies based on the emergency room and/or outpatient clinic evaluation. Among these patients, those with cardiovascular comorbidities remain at a higher risk of readmission due to ischemic stroke despite undergoing an inpatient evaluation and should therefore be the target for future preventive strategies.

A predictive analytics model for differentiating between transient ischemic attacks (TIA) and its mimics

Background

Transient ischemic attack (TIA) is a brief episode of neurological dysfunction resulting from cerebral ischemia not associated with permanent cerebral infarction. TIA is associated with high diagnostic errors because of the subjective nature of findings and the lack of clinical and imaging biomarkers. The goal of this study was to design and evaluate a novel multinomial classification model, based on a combination of feature selection mechanisms coupled with logistic regression, to predict the likelihood of TIA, TIA mimics, and minor stroke.

Methods

We conducted our modeling on consecutive patients who were evaluated in our health system with an initial diagnosis of TIA in a 9-month period. We established the final diagnoses after the clinical evaluation by independent verification from two stroke neurologists. We used Recursive Feature Elimination (RFE) and Least Absolute Shrinkage and Selection Operator (LASSO) for prediction modeling.

Results

The RFE-based classifier correctly predicts 78% of the overall observations. In particular, the classifier correctly identifies 68% of the cases labeled as “TIA mimic” and 83% of the “TIA” discharge diagnosis. The LASSO classifier had an overall accuracy of 74%. Both the RFE and LASSO-based classifiers tied or outperformed the ABCD2 score and the Diagnosis of TIA (DOT) score. With respect to predicting TIA, the RFE-based classifier has 61.1% accuracy, the LASSO-based classifier has 79.5% accuracy, whereas the DOT score applied to the dataset yields an accuracy of 63.1%.

Conclusion

The results of this pilot study indicate that a multinomial classification model, based on a combination of feature selection mechanisms coupled with logistic regression, can be used to effectively differentiate between TIA, TIA mimics, and minor stroke.

Uncertainty as a Key Influence in the Decision To Admit Patients with Transient Ischemic Attack

BACKGROUND

Patients with transient ischemic attacks (TIA) are at high risk of subsequent vascular events. Hospitalization improves quality of care, yet admission rates for TIA patients vary considerably.

OBJECTIVES

We sought to identify factors associated with the decision to admit patents with TIA.

DESIGN

We conducted a secondary analysis of a prior study's data including semi-structured interviews, administrative data, and chart review.

PARTICIPANTS

We interviewed multidisciplinary clinical staff involved with TIA care. Administrative data included information for TIA patients in emergency departments or inpatient settings at VA medical centers (VAMCs) for fiscal years (FY) 2011 and 2014. Chart reviews were conducted on a subset of patients from 12 VAMCs in FY 2011.

APPROACH

For the qualitative data, we focused on interviewees' responses to the prompt: "Tell me what influences you in the decision to or not to admit TIA patients." We used administrative data to identify admission rates and chart review data to identify ABCD² scores (a tool to classify stroke risk after TIA).

KEY RESULTS

Providers' decisions to admit TIA patients were related to uncertainty in several domains: lack of a facility TIA-specific policy, inconsistent use of ABCD² score, and concerns about facilities' ability to complete a timely workup. There was a disconnect between staff perceptions about TIA admission and facility admission rates. According to chart review data, staff at facilities with higher admission rates in FY 2011 reported consistent reliance on ABCD² scores and related guidelines in admission decision-making.

CONCLUSIONS

Many factors contributed to decisions regarding admitting a patient with TIA; however, clinicians' uncertainty appeared to be a key driver. Further quality improvement interventions for TIA care should focus on facility adoption of TIA protocols to address uncertainty in TIA admission decision-making and to standardize timely evaluation of TIA patients and delivery of secondary prevention strategies.

A challenge for psychocardiology: Addressing the causes and consequences of patients' perceptions of enduring somatic threat

The enduring somatic threat (EST) model of posttraumatic stress disorder (PTSD) due to life-threatening medical events suggests that PTSD-like symptoms represent patients' sensitization to cues of ongoing threat in the body. In this article, we review research on the prevalence and consequences of such reactions in cardiovascular disease patients, discuss early tests of the EST model, and then report a new test of the EST model in 143 patients enrolled during their first acute coronary syndrome (ACS; i.e., non-ST elevation myocardial infarction or unstable angina-colloquially, "heart attack"). Invasive coronary revascularization procedures are commonly used to reduce secondary ACS risk and may reduce patients' EST, as revascularized patients often report being "cured." We assessed ACS patients' initial threat perceptions during emergency department (ED) evaluation and followed them for 1 month for PTSD symptoms (specific for ACS, by telephone). We compared PTSD symptoms in participants who were revascularized (n = 65), catheterized but not revascularized (n = 35), and medically managed (n = 43). PTSD symptoms were lower for revascularized versus medically managed participants (B = -5.32, 95% confidence interval [-9.77, -0.87]), t(98.19) = -2.37, p = .020. In a multiple regression model adjusted for clinical and psychosocial covariates, the interaction of threat perception in the ED and ACS management group was significant (greater ED threat predicted greater 1-month PTSD symptoms only in medically managed participants). These findings offer further support for the EST model and suggest that psychological interventions to preempt patients' development of EST should be considered in the hospital. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Association Between the Subtypes of Stroke and the Various Risk Factors of Cerebrovascular Accidents: A Cross-Sectional Study

Objective

Stroke is a common heterogeneous disease classified into two subtypes: ischemic and hemorrhagic. Many risk factors have been associated with stroke, and the most well-known is hypertension. Although the relation between stroke and these risk factors has been emphasized before, there is inconclusive evidence about the relation between the different risk factors and the subtypes of stroke. The present study aims to fill this gap.

Materials and Methods

In the present retrospective, cross-sectional study, 827 patients with diagnosed stroke were included. Demographic data and the acquired risk factors were determined using pre-designed questionnaires. Statistical analysis was conducted using chi-square test, Student t-test, and Pearson correlation coefficient.

Results

Among the included 827 patients, 432 (52.2%) were men and 395 (47.8%) were women. The mean±standard deviation of age was 68.41±12.46 y in men and 67.89±11.85 y in women, respectively, and the difference was not significant. Of all the patients, 672 had ischemic strokes and 155 had hemorrhagic strokes. The most common risk factor in the patients was hypertension with a prevalence of 66.7%. Of all the risk factors, only hypertension, atrial fibrillation (AF), age, and a positive family history were significantly related to a subtype of stroke.

Conclusion

Knowing that the prevalence of hypertension, AF, age, and positive family history are significantly different between the two subtypes, the patients having these risk factors can be entered into more specified public health measures, which puts more emphasis on the subtype that they are more prone to.

Can I Send This Patient with Stroke Home? Strategies Managing Transient Ischemic Attack and Minor Stroke in the Emergency Department

BACKGROUND

While transient ischemic attack and minor stroke (TIAMS) are common conditions evaluated in the emergency department (ED), there is controversy regarding the most effective and efficient strategies for managing them in the ED. Some patients are discharged after evaluation in the ED and cared for in the outpatient setting, while others remain in an observation unit without being admitted or discharged, and others experience prolonged and potentially costly inpatient admissions.

OBJECTIVE OF THE REVIEW

The goal of this clinical review was to summarize and present recommendations regarding the disposition of TIAMS patients in the ED (e.g., admission vs. discharge).

DISCUSSION

An estimated 250,000 to 300,000 TIA events occur each year in the United States, with an estimated near-term risk of subsequent stroke ranging from 3.5% to 10% at 2 days, rising to 17% by 90 days. While popular and easy to use, reliance solely on risk-stratification tools, such as the ABCD2, should not be used to determine whether TIAMS patients can be discharged safely. Additional vascular imaging and advanced brain imaging may improve prediction of short-term neurologic risk. We also review various disposition strategies (e.g., inpatient vs. outpatient/ED observation units) with regard to their association with neurologic outcomes, such as 30-day or 90-day stroke recurrence or new stroke, in addition to other outcomes, such as hospital length of stay and health care costs.

CONCLUSIONS

Discharge from the ED for rapid outpatient follow-up may be a safe and effective strategy for some forms of minor stroke without disabling deficit and TIA patients after careful evaluation and initial ED workup. Future research on such strategies has the potential to improve neurologic and overall patient outcomes and reduce hospital costs and ED length of stay.

A systematic review and meta-analysis of published randomized controlled trials of combination of clopidogrel and aspirin in transient ischemic attack or minor stroke

The use of antiplatelet agents in patients with ischemic stroke is recommended. In this study, we compared the efficacy and safety of the treatment of clopidogrel plus aspirin (ASA) and that of ASA alone in patients with mild stroke/transient ischemic attack (TIA). Randomized controlled trial (RCT) studies of Clop + ASA vs. ASA therapy in the patients with minor stroke/TIA were identified by electronic bibliographic searches. The primary result was recurrent stroke, while myocardial infarction (MI) as well as vascular mortalities were the secondary result, and major hemorrhagic events were the safety result. A comparative analysis of binary outcomes was performed on the treatment groups, with the employment of fixed effect models and the measurement of risk ratios (95% CI). Five RCT studies involving 9,527 patients were included. Compared with the group with ASA treatment, there was significant reduction in the incidence of recurrent stroke in the group with Clop + ASA (RR=0.76, 95% CI=0.67–0.87, P<0.0001), and there was no significant increase in the incidence of vascular mortalities and MI (RR=1.08, 95% CI=0.83–1.41, P=0.56) and no significant change in major hemorrhagic events (RR=1.55, 95% CI=0.72–3.36, P=0.26). Therefore, the treatment with Clop + ASA seems safe as well as effective for decreasing stroke recurrence. In addition, this is related to a statistically insignificant trend in increasing vascular mortalities, MI, and primary hemorrhagic events. These findings need to be confirmed in prospective studies.

Impact of Hospital Admission for Patients with Transient Ischemic Attack

OBJECTIVES

To determine the impact of admission among transient ischemic attack (TIA) patients in the emergency department (ED).

STUDY DESIGN

Retrospective cohort study using national Veterans Health Administration data (2008).

METHODS

We first analyzed whether admitted patients were discharged from the hospital with a diagnosis of TIA. We then analyzed whether admission was associated with a composite outcome (new stroke, new myocardial infarction, or death in the year after TIA) using multivariate logistic regression modeling with propensity score matching.

RESULTS

Among 3623 patients assigned a diagnosis of TIA in the ED, 2118 (58%) were admitted to the hospital or placed in observation compared with 1505 (42%) who were discharged from the ED. Among the 2118 patients who were admitted, 903 (43% of admitted group) were discharged from the hospital with a diagnosis of TIA, and 548 (26% of admitted group) were discharged with a diagnosis of stroke. Admitted patients were more likely than nonadmitted patients to receive processes of care (i.e., brain imaging, carotid imaging, echocardiography). In matched analyses using propensity scores, the 1-year composite outcome in the admitted group (15.3%) was not lower than the discharged group (13.3%, OR 1.17 [.94-1.46], P = .17).

CONCLUSIONS

Less than half of patients admitted with a diagnosis of TIA retained that diagnosis at hospital discharge. Although admitted patients were more likely to receive diagnostic procedures, we did not identify improvements in outcomes among admitted patients; however, evaluating care for patients with TIA is limited by the reliability of secondary data analysis.

Trends in Transient Ischemic Attack Hospitalizations in the United States

Background

Transient ischemic attack (TIA) is a major predictor of subsequent stroke. No study has assessed nation‐wide trends in hospitalization for TIA in the United States.

Methods and Results

Temporal trends in hospitalization for TIA (International Classification of Diseases, Ninth Revision code 435.0–435.9) from 2000 to 2010 were assessed among adults aged ≥25 years using the Nationwide Inpatient Sample. Age‐, sex‐, and race/ethnic‐specific TIA hospitalization rates were calculated using the weighted number of hospitalizations as the numerator and the US population as the denominator. Age‐adjusted rates were standardized to the 2000 US Census population. From 2000 to 2010, age‐adjusted TIA hospitalization rates decreased from 118 to 83 per 100 000 (overall rate reduction, −29.7%). Age‐specific TIA hospitalization rates increased for individuals aged 24 to 44 years (10–11 per 100 000), but decreased for individuals aged 45 to 64 (74 to 65 per 100 000), 65 to 84 (398 to 245 per 100 000), and ≥85 years (900 to 619 per 100 000). Blacks had the highest age‐adjusted yearly hospitalization rates, followed by Hispanics and whites (124, 82, and 67 per 100 000 in 2010). Rates slightly increased for blacks, but decreased for Hispanics and whites. Compared to women, age‐adjusted TIA hospitalization rates were lower and declined more steeply in men (132 to 89 per 100 000 versus 134 to 97 per 100 000).

Conclusions

Although overall TIA hospitalizations have decreased in the United States, the reduction has been more pronounced among older individuals, men, whites, and Hispanics. These findings highlight the need to target risk‐factor control among women, blacks, and individuals aged <45 years.

Hemodynamic variability and cerebrovascular control after transient cerebral ischemia

We investigated if hemodynamic variability, cerebral blood flow (CBF) regulation, and their interrelationships differ between patients with transient ischemic attack (TIA) and controls. We recorded blood pressure (BP) and bilateral middle cerebral artery flow velocity (MCAv) in a cohort of TIA patients (n = 17), and age-matched controls (n = 15). Spontaneous fluctuations in BP and MCAv were characterized by spectral power analysis, and CBF regulation was assessed by wavelet phase synchronization analysis in the very low- (0.02–0.07 Hz), low- (0.07–0.20 Hz), and high-frequency (0.20–0.40 Hz) ranges. Furthermore, cerebrovascular CO₂ reactivity was assessed as a second metric of CBF regulation by inducing hypercapnia with 8% CO₂ inhalation followed by hyperventilation driven hypocapnia. We found that TIA was associated with higher BP power (group effect, P < 0.05), but not MCAv power (P = 0.11). CBF regulation (assessed by wavelet phase synchronization and CO₂ reactivity) was intact in patients (all P ≥ 0.075) across both hemispheres (all P ≥ 0.51). Pooled data (controls and affected hemisphere of patients) showed that BP and MCAv power were positively correlated at all frequency ranges (R² = 0.20–0.80, all P < 0.01). Furthermore, LF phase synchronization index was a significant determinant of MCAv power (P < 0.05), while VLF and HF phase synchronization index, and TIA were not (all P ≥ 0.50). These results indicate that CBF stability and control is maintained in TIA patients, but BPV is markedly elevated. BPV attenuation may be an important therapeutic strategy for enhancing secondary stroke prevention in patients who suffer a TIA.

Treatment of Rivaroxaban versus Aspirin for Non-disabling Cerebrovascular Events (TRACE): study protocol for a randomized controlled trial

BACKGROUND

Transient ischemic attack (TIA) or minor ischemic stroke represents the largest group of cerebrovascular disease, and those patients have a high risk of early recurrent stroke. Over decades, anticoagulation therapy has been used prudently in them for likely increasing the risk of intra-/extra-cranial hemorrhagic complications. However, recently rivaroxaban, a new oral anticoagulant, is proved to be as effective as traditional anticoagulants, while carrying significantly less risk of intracranial hemorrhage. Therefore, we assumed that patients may benefit from rivaroxaban if treated soon after TIA or minor stroke, and designed this adequately powered randomized study, TRACE.

METHODS AND DESIGN

The Treatment of Rivaroxaban versus Aspirin in Non-disabling Cerebrovascular Events (TRACE) study is a randomized, double-blind clinical trial with a target enrollment of 4400 patients. A 14-days regimen of rivaroxaban 10 mg daily or a 14-days regimen of aspirin 100 mg daily will be administrated to randomized participants with acute TIA or minor stroke, defined as National Institute of Health Stroke Scale scores ≤ 3. The primary efficacy end point is percentage of patients with any stroke (ischemic or hemorrhage) at 14 days. Study visits will be performed at the day of randomization, day 14 and day 90.

DISCUSSION

Even though the new oral anticoagulants seem to be both safe and effective, few clinical trials have been carried out to test their effect on non-disabling cerebrovascular events. Treatment with rivaroxaban may prevent more cerebrovascular events with an acceptable risk profile after TIA or minor stroke, compared with aspirin, thus helping to improve the outcome of the disease.

TRIAL REGISTRATION

No. NCT01923818.

Incorporating diffusion-weighted magnetic resonance imaging into an observation unit transient ischemic attack pathway: a prospective study

BACKGROUND AND PURPOSE

National guidelines advocate for early, aggressive transient ischemic attack (TIA) evaluations and recommend diffusion-weighted magnetic resonance imaging (MRI) for brain imaging. The purpose of this study is to examine clinician compliance, the yield of MRI, and patient-centered clinical outcomes following implementation of an emergency department observation unit (EDOU) clinical pathway incorporating routine MRI into the acute evaluation of patients with TIA.

METHODS

This is a prospective observational study of patients with TIA admitted from the ED. Patients with low-risk TIA were transferred to an EDOU for diagnostic testing including MRI; high-risk patients were directed to hospital admission. Clinical variables, diagnostic tests, and treatment were recorded for all patients. The primary clinical outcome was the rate of stroke or recurrent TIA, determined through telephone follow-up and medical record review at 7 and 30 days.

RESULTS

A total of 116 patients with TIA were enrolled. In all, 92 (79.3%) patients were transferred to the EDOU, of whom 69 (59.5%) were discharged without hospitalization. Compliance with the EDOU pathway was 83 (91.2%) of 92. Magnetic resonance imaging demonstrated acute infarct in 16 (15.7%) of 102 patients. Stroke (n = 2) or TIA (n = 3) occurred in 5 patients with TIA (4.3%, 95% confidence interval: 1.6%-10.0%) within 30 days; no strokes occurred after discharge.

CONCLUSIONS

Implementation of a TIA clinical pathway incorporating MRI effectively encouraged guideline-compliant diagnostic testing; however, patient-important outcomes appear similar to diagnostic protocols without routine MRI. Further study is needed to assess the benefits and costs associated with routinely incorporating MRI into TIA evaluation.

The incidence and clinical predictors of acute infarction in patients with transient ischemic attack using MRI including DWI

INTRODUCTION

According to the most recent definition of transient ischemic attack (TIA) and the recommendations of the American Heart Association, magnetic resonance imaging (MRI) including diffusion-weighted imaging (DWI) is considered a mandatory tool in evaluating and treating patients with TIA. This study aims to determine the incidence of TIA-related acute infarction, identify the independent predictors of acute infarction, and investigate the correlation between acute infarction detected by DWI-MRI and stroke risk during hospitalization.

METHODS

Over a 36-month period (starting November 2007), all TIA patients (symptom duration of <24 h) who were admitted to hospital within 48 h of symptom onset and who underwent DWI-MRI were included in this population-based prospective study. The incidence of acute infarction, clinical predictors, and association with stroke recurrence during hospitalization were studied.

RESULTS

Of 1,910 patients (mean age, 66.7 ± 13 years; 46 % women), 1,862 met the inclusion criteria. A TIA-related acute infarction was detected in 206 patients (11.1 %). Several independent predictors were identified with logistic regression analysis: motor weakness [odds ratio (OR), 1.5], aphasia (OR, 1.6), National Institutes of Health Stroke Scale (NIHSS) score of ≥10 at admission (OR, 3.2), and hyperlipidemia (OR, 0.6). Of 24 patients (1.3 %) who suffered a stroke during hospitalization (mean, 6 ± 4 days), five had positive DWI. Stroke rate during hospitalization was nonsignificantly higher in patients with positive DWI than those with negative DWI (2.4 vs 1.1 %, respectively; P = 0.12).

CONCLUSION

The evidence of acute infarction by DWI-MRI in TIA patients was detected in 11.1 % of patients and associated with motor weakness, aphasia, and NIHSS score of ≥10 at admission.

Use of cranial CT to identify a new infarct in patients with a transient ischemic attack

Research on infarct detection by noncontrast cranial computed tomography (CCT) in patients with transient ischemic attack (TIA) is sparse. However, the aims of this study are to determine the frequency of new infarcts in patients with TIA, to evaluate the independent predictors of infarct detection, and to investigate the association between a new infarct and early short-term risk of stroke during hospitalization. We prospectively evaluated 1533 consecutive patients (mean age, 75.3 ± 11 years; 54% female; mean National Institutes of Health Stroke Scale [NIHSS] score, 1.7 ± 2.9) with TIA who were admitted to hospital within 48 h of symptom onset. A new infarct was detected by CCT in 47 (3.1%) of the 1533 patients. During hospitalization, 17 patients suffered a stroke. Multivariate logistic regression analysis revealed the following independent predictors for infarct detection: NIHSS score ≥10 (odds ratio [OR], 4.8), time to CCT assessment >6 h (OR 2.2), and diabetes (OR 2.3). The evidence of a new infarct was not associated with the risk of stroke after TIA. The frequency of a new infarct in patients with TIA using CCT is low. The use of the CCT tool to predict the stroke risk during hospitalization in patients with TIA is found to be inappropriate. The estimated clinical predictors are easy to use and may help clinicians in the TIA work up.

Transient ischemic attack: definition, diagnosis, and risk stratification

Transient ischemic attack (TIA) can convey a high imminent risk for the development of a major stroke and is therefore considered to be a medical emergency. Recent evidence indicates that TIA with imaging proof of brain infarction represents an extremely unstable condition with early risk of stroke that is as much as 20 times higher than the risk after TIA without tissue damage. The use of neuroimaging in TIA is therefore critical not only for diagnosis but also for accurate risk stratification. In this article, recent advances in diagnostic imaging, categorizations, and risk stratification in TIA are discussed.

The ABCD and ABCD2 Scores and the Risk of Stroke following a TIA: A Narrative Review

The California, ABCD, and ABCD2 risk scores (ABCD system) were developed to help stratify short-term stroke risk in patients with TIA (transient ischemic attack). Beyond this scope, the ABCD system has been extensively used to study other prognostic information such as DWI (diffusion-weighted imaging) abnormalities, large artery stenosis, atrial fibrillation and its diagnostic accuracy in TIA patients, which are independent predictors of subsequent stroke in TIA patients. Our comprehensive paper suggested that all scores have and equivalent prognostic value in predicting short-term risk of stroke; however, the ABCD2 score is being predominantly used at most centers. The majority of studies have shown that more than half of the strokes in the first 90 days, occur in the first 7 days. The majority of patients studied were predominantly classified to have a higher ABCD/ABCD2 > 3 scores and were particularly at a higher short-term risk of stroke or TIA and other vascular events. However, patients with low risk ABCD2 score < 4 may have high-risk prognostic indicators, such as diffusion weighted imaging (DWI) abnormalities, large artery atherosclerosis (LAA), and atrial fibrillation (AF). The prognostic value of these scores improved if used in conjunction with clinical information, vascular imaging data, and brain imaging data. Before more data become available, the diagnostic value of these scores, its applicability in triaging patients, and its use in evaluating long-term prognosis are rather secondary; thus, indicating that the primary significance of these scores is for short-term prognostic purposes.

Prospective validation of the ABCD2 score for patients in the emergency department with transient ischemic attack

BACKGROUND

The ABCD2 score (Age, Blood pressure, Clinical features, Duration of symptoms and Diabetes) is used to identify patients having a transient ischemic attack who are at high risk for imminent stroke. However, despite its widespread implementation, the ABCD2 score has not yet been prospectively validated. We assessed the accuracy of the ABCD2 score for predicting stroke at 7 (primary outcome) and 90 days.

METHODS

This prospective cohort study enrolled adults from eight Canadian emergency departments who had received a diagnosis of transient ischemic attack. Physicians completed data forms with the ABCD2 score before disposition. The outcome criterion, stroke, was established by a treating neurologist or by an Adjudication Committee. We calculated the sensitivity and specificity for predicting stroke 7 and 90 days after visiting the emergency department using the original "high-risk" cutpoint of an ABCD2 score of more than 5, and the American Heart Association recommendation of a score of more than 2.

RESULTS

We enrolled 2056 patients (mean age 68.0 yr, 1046 (50.9%) women) who had a rate of stroke of 1.8% at 7 days and 3.2% at 90 days. An ABCD2 score of more than 5 had a sensitivity of 31.6% (95% confidence interval [CI] 19.1-47.5) for stroke at 7 days and 29.2% (95% CI 19.6-41.2) for stroke at 90 days. An ABCD2 score of more than 2 resulted in sensitivity of 94.7% (95% CI 82.7-98.5) for stroke at 7 days with a specificity of 12.5% (95% CI 11.2-14.1). The accuracy of the ABCD2 score as calculated by either the enrolling physician (area under the curve 0.56; 95% CI 0.47-0.65) or the coordinating centre (area under the curve 0.65; 95% CI 0.57-0.73) was poor.

INTERPRETATION

This multicentre prospective study involving patients in emergency departments with transient ischemic attack found the ABCD2 score to be inaccurate, at any cut-point, as a predictor of imminent stroke. Furthermore, the ABCD2 score of more than 2 that is recommended by the American Heart Association is nonspecific.

How much would performing diffusion-weighted imaging for all transient ischemic attacks increase MRI utilization?

OBJECTIVES

The American Heart Association recently redefined TIA to exclude patients with infarction on neuroimaging. Given its advantages, MRI/diffusion-weighted imaging (DWI) was recommended as the preferred imaging modality. We determined how frequently MRI/DWI was performed for TIA and ascertained the proportion of clinically defined TIA patients who had ischemic lesions on DWI in our community in 2005.

METHODS

All clinically defined TIA cases among residents of a 5-county region around Cincinnati who presented to emergency departments were identified during 2005. Demographics and medical history, whether MRI/DWI was performed, and DWI findings were recorded. Generalized estimating equations were used to compare groups to account for the design of the study and multiple events per patient.

RESULTS

Of 834 TIA events in 799 patients, 323 events (40%) had MRI/DWI performed. Patients who had MRI/DWI were younger (mean, 66 vs 70 years; P=0.03), had less severe prestroke disability (baseline modified Rankin Scale score, 0; 44% vs 34%; P=0.02), were less likely to have previous stroke or TIA (42% vs 56%; P=0.002), and were less likely to have atrial fibrillation (10% vs 16%; P=0.01). Of the 323 events with DWI, 51 (15%) had evidence of acute infarction. Patients with positive DWI were older (75 vs 64 years; P=0.0001) and more likely to have atrial fibrillation (21% vs 7%; P=0.002).

CONCLUSIONS

Performing MRI/DWI on all clinically defined TIA patients in our community would reveal more cases of actual infarction but would more than double current use. Future studies should assess whether MRI/DWI is warranted for all TIA patients.

Urgent neurology consultation from the ED for transient ischemic attack

OBJECTIVE

The objective of this study was to evaluate the association between urgent neurology consultation and outcomes for patients with transient ischemic attack (TIA).

METHODS

In a secondary analysis of data from 1707 emergency department patients with transient ischemic attack from March 1997 to May 1998, we compared presentation, management, and outcomes by neurology consultation status using generalized estimating equations to adjust for ABCD(2) score and clustering by facility and survival analysis for outcomes.

RESULTS

Consultation was obtained f28% of patients. Median ABCD(2) scores were comparable, but consultation was associated with hospital admission (odds ratio, 1.35 [1.02-1.78], P = .04) and use of antithrombotics (odds ratio, 1.88 [1.20-2.93], P = .005). The cumulative stroke risk was significantly lower within 1 week (5.3% versus 7.5%, P = .02) but not at 90 days (9.9% versus 11.0%, P = .21).

CONCLUSIONS

Consultation was not targeted to high-risk patients but was associated with some quality of care measures and improved early outcomes; however, improvement in 90-day outcomes was not established.

Evaluation of transient ischemic attack in an emergency department observation unit

OBJECTIVE

To evaluate the feasibility of a protocol for evaluation of transient ischemic attack (TIA) in an Emergency Department Observation Unit (EDOU), and assess the risk of early stroke after such an evaluation.

METHODS

All adult patients presenting to the Emergency Department (ED) with signs and symptoms consistent with TIA were prospectively enrolled in this observational study over a period of 3 years. Patients underwent a standardized TIA evaluation per protocol. Risk of subsequent stroke at 48 h, 1 week, 1 month, and 3 months was prospectively assessed.

RESULTS

In total, 418 patients were seen during the study period, and all were evaluated per the EDOU TIA protocol. The mean age was 73.1 (+/-13.3) years and 53.8% were males. Comorbidities included hypertension in 71.5%, diabetes mellitus in 20.1%, prior TIA in 19.6%, and prior ischemic stroke in 19.6% of the cohort. Brain CT, neurology consult, electrocardiogram, carotid ultrasound, and additional tests were performed, and education was given. A total of 30.4% of the patients were dismissed directly from the EDOU. The risk of stroke at 2 days was 0.96%, at 7 days 1.2%, at 30 days 1.9%, and 2.4% at 90 days.

CONCLUSION

An Emergency Department Observation Unit Protocol for TIA is a feasible option for expedited evaluation of these patients.

Characteristics of TIA and its management in a tertiary care hospital in Pakistan

BACKGROUND

Transient ischemic attack (TIA) is described as a brief episode of neurological dysfunction caused by focal brain ischemia, with clinical symptoms typically lasting less than an hour, and without evidence of acute infarction. Recent studies depict TIA as a particularly unstable condition. Risk of stroke is greater than 10% in the first 90 days after an index TIA. The presentation, prognosis and intervention for TIA have not been reported in South-Asians in a developing country.

METHOD

A retrospective chart review was done for 158 patients who were admitted with the diagnosis of TIA, as defined by ICD 9 code 435, from January 2003 to December 2005 at the Aga Khan University Hospital, Karachi, Pakistan. The data was entered and analyzed in SPSS version 14.0.

FINDINGS

Among 158 patients, 57.6% were male and 41.1% were female. The common presenting symptoms were motor symptoms (51.3%), speech impairment (43%), sensory impairment (34.8%) and loss of balance/vertigo (29.1%). The median delay in presenting to the hospital was 4 hours. Those with motor symptoms were found to present earlier. The study showed that only 60.8% of all the patients presenting with TIA received any immediate treatment out of which 44.7% received aspirin. Neuroimaging was used in 91.1% of the patients. Of all the TIA patients 9.1% converted to stroke with 50% doing so within the first 24 hours.

CONCLUSION

The natural history of TIA from this developing nation is comparable to international descriptions. A large percentage of patients are still not receiving any immediate treatment as recommended in available guidelines, even in a tertiary care hospital.