Risk of recurrent stroke in patients with atrial fibrillation treated with oral anticoagulants alone or in combination with anti-platelet therapy

INTRODUCTION

Ischaemic stroke patients with atrial fibrillation (AF) are at high risk of stroke recurrence despite oral anticoagulation therapy. Patients with cardiovascular comorbidities may take both antiplatelet and oral anticoagulation therapy (OAC/AP). Our study aims to evaluate the safety and efficacy of OAC/AP therapy as secondary prevention in people with AF and ischaemic stroke.

PATIENTS AND METHODS

We performed a post-hoc analysis of pooled individual data from multicenter prospective cohort studies and compared outcomes in the OAC/AP cohort and patients on DOAC/VKA anticoagulation alone (OAC cohort). Primary outcome was a composite of ischaemic stroke, systemic embolism, intracranial bleeding, and major extracranial bleeding, while secondary outcomes were ischaemic and haemorrhagic events considered separately. A multivariable logistic regression analysis was performed to identify independent predictors for outcome events. To compare the risk of outcome events between the two cohorts, the relation between the survival function and the set of explanatory variables were calculated by Cox proportional hazard models and the results were reported as adjusted hazard ratios (HR). Finally another analysis was performed to compare the overall risk of outcome events in both OAC/AP and OAC cohorts after propensity score matching (PSM).

RESULTS

During a mean follow-up time of 7.5 ± 9.1 months (median follow-up time 3.5 months, interquartile range ±3), 2284 stroke patients were on oral anticoagulants and 215 were on combined therapy. The multivariable model demonstrated that the composite outcome is associated with age (OR: 1.03, 95% CI: 1.01-1.04 for each year increase) and concomitant antiplatelet therapy (OR: 2.2, 95% CI: 1.48-3.27), the ischaemic outcome with congestive heart failure (OR: 1.55, 95% CI: 1.02-2.36) and concomitant antiplatelet therapy (OR: 1.93, 95% CI: 1.19-3.13) and the haemorrhagic outcome with age (OR: 1.03, 95% CI: 1.01-1.06 for each year increase), alcoholism (OR: 2.15, 95% CI: 1.06-4.39) and concomitant antiplatelet therapy (OR: 2.22, 95% CI: 1.23-4.02). Cox regression demonstrated a higher rate of the composite outcome (hazard ratio of 1.93 [95% CI, 1.35-2.76]), ischaemic events (HR: 2.05 [95% CI: 1.45-2.87]) and bleeding outcomes (HR: 1.90 [95% CI, 1.06-3.40]) in OAC/AP cohort. After PSM analysis, the composite outcome remained more frequent in people treated with OAC + AP (RR: 1.70 [95% CI, 1.05-2.74]).

DISCUSSION

Secondary prevention with combination of oral anticoagulant and antiplatelet therapy after ischaemic stroke was associated with worse outcomes in our cohort.

CONCLUSION

Further research is needed to improve secondary prevention by investigating the mechanisms of recurrent ischaemic stroke in patients with atrial fibrillation.

Telestroke Across the Continuum of Care: Lessons from the COVID-19 Pandemic

While use of telemedicine to guide emergent treatment of ischemic stroke is well established, the COVID-19 pandemic motivated the rapid expansion of care via telemedicine to provide consistent care while reducing patient and provider exposure and preserving personal protective equipment. Temporary changes in re-imbursement, inclusion of home office and patient home environments, and increased access to telehealth technologies by patients, health care staff and health care facilities were key to provide an environment for creative and consistent high-quality stroke care. The continuum of care via telestroke has broadened to include prehospital, inter-facility and intra-facility hospital-based services, stroke telerehabilitation, and ambulatory telestroke. However, disparities in technology access remain a challenge. Preservation of reimbursement and the reduction of regulatory burden that was initiated during the public health emergency will be necessary to maintain expanded patient access to the full complement of telestroke services. Here we outline many of these initiatives and discuss potential opportunities for optimal use of technology in stroke care through and beyond the pandemic.

Timing of initiation of oral anticoagulants in patients with acute ischemic stroke and atrial fibrillation comparing posterior and anterior circulation strokes

Introduction

The aim of this study in patients with acute posterior ischaemic stroke (PS) and atrial fibrillation (AF) was to evaluate (1) the risks of recurrent ischaemic event and severe bleeding and (2) these risks in relation with oral anticoagulant therapy (OAT) and its timing.

Materials and Methods

Patients with PS were prospectively included; the outcome events of these patients were compared with those of patients with anterior stroke (AS) which were taken from previous registries. The primary outcome was the composite of stroke recurrence, transient ischaemic attack, symptomatic systemic embolism, symptomatic cerebral bleeding and major extracranial bleeding occurring within 90 days from acute stroke.

Results

A total of 2470 patients were available for the analysis: 473 (19.1%) with PS and 1997 (80.9%) with AS. Over 90 days, 213 (8.6%) primary outcome events were recorded: 175 (8.7%) in patients with AS and 38 (8.0%) in those with PS. In patients who initiated OAT within 2 days, the primary outcome occurred in 5 out of 95 patients (5.3%) with PS compared to 21 out of 373 patients (4.3%) with AS (OR 1.07; 95% CI 0.39-2.94). In patients who initiated OAT between days 3 and 7, the primary outcome occurred in 3 out of 103 patients (2.9%) with PS compared to 26 out of 490 patients (5.3%) with AS (OR 0.54; 95% CI 0.16-1.80).

Discussion

our findings suggest that, when deciding the time to initiate oral anticoagulation, the location of stroke, either anterior or posterior, does not predict the risk of outcome events.

Conclusions

Patients with PS or AS and AF appear to have similar risks of ischaemic or haemorrhagic events at 90 days with no difference concerning the timing of initiation of OAT.

Safety of Anticoagulation in Patients Treated With Urgent Reperfusion for Ischemic Stroke Related to Atrial Fibrillation

BACKGROUND AND PURPOSE

The optimal timing for starting oral anticoagulant after an ischemic stroke related to atrial fibrillation remains a challenge, mainly in patients treated with systemic thrombolysis or mechanical thrombectomy. We aimed at assessing the incidence of early recurrence and major bleeding in patients with acute ischemic stroke and atrial fibrillation treated with thrombolytic therapy and/or thrombectomy, who then received oral anticoagulants for secondary prevention.

METHODS

We combined the dataset of the RAF and the RAF-NOACs (Early Recurrence and Major Bleeding in Patients With Acute Ischemic Stroke and Atrial Fibrillation Treated With Non-Vitamin K Oral Anticoagulants) studies, which were prospective observational studies carried out from January 2012 to March 2014 and April 2014 to June 2016, respectively. We included consecutive patients with acute ischemic stroke and atrial fibrillation treated with either vitamin K antagonists or nonvitamin K oral anticoagulants. Primary outcome was the composite of stroke, transient ischemic attack, symptomatic systemic embolism, symptomatic cerebral bleeding, and major extracerebral bleeding within 90 days from the inclusion. Treated-patients were propensity matched to untreated-patients in a 1:1 ratio after stratification by baseline clinical features.

RESULTS

A total of 2159 patients were included, 564 (26%) patients received acute reperfusion therapies. After the index event, 505 (90%) patients treated with acute reperfusion therapies and 1287 of 1595 (81%) patients untreated started oral anticoagulation. Timing of starting oral anticoagulant was similar in reperfusion-treated and untreated patients (median 7.5 versus 7.0 days, respectively). At 90 days, the primary study outcome occurred in 37 (7%) patients treated with reperfusion and in 146 (9%) untreated patients (odds ratio, 0.74 [95% CI, 0.50-1.07]). After propensity score matching, risk of primary outcome was comparable between the 2 groups (odds ratio, 1.06 [95% CI, 0.53-2.02]).

CONCLUSIONS

Acute reperfusion treatment did not influence the risk of early recurrence and major bleeding in patients with atrial fibrillation-related acute ischemic stroke, who started on oral anticoagulant.

Recommended Strategies for Physician Burnout, a Well-Recognized Escalating Global Crisis Among Neurologists

Several indexes are used to classify physician burnout, with the Maslach Burnout Inventory currently being the most widely accepted. This index measures physician burnout based on emotional exhaustion, detachment from work, and lack of personal achievement. The overall percentage of physicians with burnout is estimated to be around 40%, but the proportion varies between specialties. Neurology currently has the second-highest rate of burnout and is projected to eventually take the top position. The purpose of this review is to provide a comprehensive overview focusing on the causes and ramifications of burnout and possible strategies for addressing the crisis. Several factors contribute to burnout among neurologist, including psychological trauma associated with patient care and a lack of respect compared to other specialties. Various interventions have been proposed for reducing burnout, and this article explores the feasibility of some of them. Burnout not only impacts the physician but also has adverse effects on the overall quality of patient care and places a strain on the health-care system. Burnout has only recently been recognized and accepted as a health crisis globally, and hence most of the proposed action plans have not been validated. More studies are needed to evaluate the long-term effects of such interventions.

Hemorrhagic Transformation in Patients With Acute Ischemic Stroke and Atrial Fibrillation: Time to Initiation of Oral Anticoagulant Therapy and Outcomes

Background

In patients with acute ischemic stroke and atrial fibrillation, early anticoagulation prevents ischemic recurrence but with the risk of hemorrhagic transformation (HT). The aims of this study were to evaluate in consecutive patients with acute stroke and atrial fibrillation (1) the incidence of early HT, (2) the time to initiation of anticoagulation in patients with HT, (3) the association of HT with ischemic recurrences, and (4) the association of HT with clinical outcome at 90 days.

Methods and Results

HT was diagnosed by a second brain computed tomographic scan performed 24 to 72 hours after stroke onset. The incidence of ischemic recurrences as well as mortality or disability (modified Rankin Scale scores >2) were evaluated at 90 days. Ischemic recurrences were the composite of ischemic stroke, transient ischemic attack, or systemic embolism. Among the 2183 patients included in the study, 241 (11.0%) had HT. Patients with and without HT initiated anticoagulant therapy after a mean 23.3 and 11.6 days, respectively, from index stroke. At 90 days, 4.6% (95% confidence interval, 2.3–8.0) of the patients with HT had ischemic recurrences compared with 4.9% (95% confidence interval, 4.0–6.0) of those without HT; 53.1% of patients with HT were deceased or disabled compared with 35.8% of those without HT. On multivariable analysis, HT was associated with mortality or disability (odds ratio, 1.71; 95% confidence interval, 1.24–2.35).

Conclusions

In patients with HT, anticoagulation was initiated about 12 days later than patients without HT. This delay was not associated with increased detection of ischemic recurrence. HT was associated with increased mortality or disability.

Anticoagulation After Stroke in Patients With Atrial Fibrillation

Background and Purpose- Bridging therapy with low-molecular-weight heparin reportedly leads to a worse outcome for acute cardioembolic stroke patients because of a higher incidence of intracerebral bleeding. However, this practice is common in clinical settings. This observational study aimed to compare (1) the clinical profiles of patients receiving and not receiving bridging therapy, (2) overall group outcomes, and (3) outcomes according to the type of anticoagulant prescribed. Methods- We analyzed data of patients from the prospective RAF and RAF-NOACs studies. The primary outcome was defined as the composite of ischemic stroke, transient ischemic attack, systemic embolism, symptomatic cerebral bleeding, and major extracerebral bleeding observed at 90 days after the acute stroke. Results- Of 1810 patients who initiated oral anticoagulant therapy, 371 (20%) underwent bridging therapy with full-dose low-molecular-weight heparin. Older age and the presence of leukoaraiosis were inversely correlated with the use of bridging therapy. Forty-two bridged patients (11.3%) reached the combined outcome versus 72 (5.0%) of the nonbridged patients (P=0.0001). At multivariable analysis, bridging therapy was associated with the composite end point (odds ratio, 2.3; 95% CI, 1.4-3.7; P<0.0001), as well as ischemic (odds ratio, 2.2; 95% CI, 1.3-3.9; P=0.005) and hemorrhagic (odds ratio, 2.4; 95% CI, 1.2-4.9; P=0.01) end points separately. Conclusions- Our findings suggest that patients receiving low-molecular-weight heparin have a higher risk of early ischemic recurrence and hemorrhagic transformation compared with nonbridged patients.

Early recurrence in paroxysmal versus sustained atrial fibrillation in patients with acute ischaemic stroke

Background

The relationship between different patterns of atrial fibrillation and early recurrence after an acute ischaemic stroke is unclear.

Purpose

In a prospective cohort study, we evaluated the rates of early ischaemic recurrence after an acute ischaemic stroke in patients with paroxysmal atrial fibrillation or sustained atrial fibrillation which included persistent and permanent atrial fibrillation.

Methods

In patients with acute ischaemic stroke, atrial fibrillation was categorised as paroxysmal atrial fibrillation or sustained atrial fibrillation. Ischaemic recurrences were the composite of ischaemic stroke, transient ischaemic attack and symptomatic systemic embolism occurring within 90 days from acute index stroke.

Results

A total of 2150 patients (1155 females, 53.7%) were enrolled: 930 (43.3%) had paroxysmal atrial fibrillation and 1220 (56.7%) sustained atrial fibrillation. During the 90-day follow-up, 111 ischaemic recurrences were observed in 107 patients: 31 in patients with paroxysmal atrial fibrillation (3.3%) and 76 with sustained atrial fibrillation (6.2%) (hazard ratio (HR) 1.86 (95% CI 1.24-2.81)). Patients with sustained atrial fibrillation were on average older, more likely to have diabetes mellitus, hypertension, history of stroke/ transient ischaemic attack, congestive heart failure, atrial enlargement, high baseline NIHSS-score and implanted pacemaker. After adjustment by Cox proportional hazard model, sustained atrial fibrillation was not associated with early ischaemic recurrences (adjusted HR 1.23 (95% CI 0.74-2.04)).

Conclusions

After acute ischaemic stroke, patients with sustained atrial fibrillation had a higher rate of early ischaemic recurrence than patients with paroxysmal atrial fibrillation. After adjustment for relevant risk factors, sustained atrial fibrillation was not associated with a significantly higher risk of recurrence, thus suggesting that the risk profile associated with atrial fibrillation, rather than its pattern, is determinant for recurrence.

Abstract 86: Nationwide Differences in Care and Outcomes of Acute Ischemic Stroke

Background: Acute Ischemic Stroke (AIS) remains a leading cause of mortality and morbidity in United States, and poses a major socio-economic burden. Efforts are underway to standardize systems of care for acute stroke treatment. We aim to assess if, despite the attempts towards standardization, regional difference in stroke care practice pattern, cost and/ or outcomes persist.

Methods: Healthcare Cost and Utilization Project's Nationwide Inpatient Sample database was reviewed from 2002 to 2014. Hospitalizations with AIS were identified using ICD-9-CM codes 433.xx-436, tPA use by procedure code 99.10. Care is determined based on tPA utilization, length of stay, and cost of hospitalization. Outcomes are determined based on discharge disposition (home or facility) and death. These were further analyzed based on regions; Northeast, South, Midwest and West. Multivariate linear regression model and Cochran Armitage trend test used for the analysis.

Results: AIS admissions increased throughout the US, more so in the South. There is an increase in tPA utilization all regions, which is significantly higher in the West compared to other regions. Midwest and South have significantly lower cost of hospitalization compared to West despite having higher length of stay. (Graph).

Conclusion: AIS care is noted to be remarkably non-uniform across the USA. This lack of uniformity seems to affect outcomes. Further studies are required to determine the causation of these findings.

Abstract TP4: Current Practices and Discharge Outcome of Endovascular Coiling and Clipping Amongst Hemorrhagic Stroke Patients

Background: 20% of strokes are hemorrhagic (HS), with subarachnoid hemorrhage (SAH) and intracerebral hemorrhage each accounting for 10%. Most SAHs are caused by ruptured saccular aneurysms. Therapeutic advances like endovascular coiling (EvC) and clipping have added to the armamentarium for treating this malignant process.

Methods: Data from Nationwide Inpatient Sample (NIS) (years 2003-2013) was analyzed to identify HS (aSAH and ICH) hospitalization using ICD-9-CM codes. EvC and clipping patients were identified from the cohort. A retrospective analysis with multivariate survey logistic regression was done to evaluate the predictors of utilizations of EvC and clipping.

Results: From years 2003 to 2013, total 1,004,736 patients with HS were hospitalized. Out of them, 47,999 (4.7%) patients had EvC and 55,900 (5.6%) patients had clipping. Predictors of higher EvC utilization were young 35-50 years patients (aOR: 1.20; 95%CI: 1.04-1.38), large hospitals (>100 beds) (aOR: 4.53; 95%CI: 3.54-5.81), and urban teaching hospitals (aOR: 4.66; 95%CI: 3.63-5.97). Clipping utilization was higher among age 65-80 years patients (aOR: 2.02; 95%CI: 1.73-2.37) and age >80 years (aOR: 5.15; 95%CI: 4.25-6.23), male (aOR: 2.02; 95%CI: 1.89-2.15), emergency admissions (aOR: 1.73; 95%CI: 1.52-1.97), and pre-existing co-morbidities like renal failure, solid tumor, hypertension, and diabetes. Utilization of EvC was associated with lower frequencies of in poor discharge disposition: transferred to short-term hospital/skilled nursing facility/intermediate care/long term care facility (45.86% vs. 49.75%; p<0.001) in comparison to clipping.

Discussion: Historically, coiling was reserved for the treatment of high-grade subarachnoid bleed, has found to be not only safe but also favourable with better discharge disposition. The recent AHA guideline and multiple research trials have shown the same result.

Early Recurrence and Major Bleeding in Patients With Acute Ischemic Stroke and Atrial Fibrillation Treated With Non-Vitamin-K Oral Anticoagulants (RAF-NOACs) Study

BACKGROUND

The optimal timing to administer non-vitamin K oral anticoagulants (NOACs) in patients with acute ischemic stroke and atrial fibrillation is unclear. This prospective observational multicenter study evaluated the rates of early recurrence and major bleeding (within 90 days) and their timing in patients with acute ischemic stroke and atrial fibrillation who received NOACs for secondary prevention.

METHODS AND RESULTS

Recurrence was defined as the composite of ischemic stroke, transient ischemic attack, and symptomatic systemic embolism, and major bleeding was defined as symptomatic cerebral and major extracranial bleeding. For the analysis, 1127 patients were eligible: 381 (33.8%) were treated with dabigatran, 366 (32.5%) with rivaroxaban, and 380 (33.7%) with apixaban. Patients who received dabigatran were younger and had lower admission National Institutes of Health Stroke Scale score and less commonly had a CHA₂DS₂-VASc score >4 and less reduced renal function. Thirty-two patients (2.8%) had early recurrence, and 27 (2.4%) had major bleeding. The rates of early recurrence and major bleeding were, respectively, 1.8% and 0.5% in patients receiving dabigatran, 1.6% and 2.5% in those receiving rivaroxaban, and 4.0% and 2.9% in those receiving apixaban. Patients who initiated NOACs within 2 days after acute stroke had a composite rate of recurrence and major bleeding of 12.4%; composite rates were 2.1% for those who initiated NOACs between 3 and 14 days and 9.1% for those who initiated >14 days after acute stroke.

CONCLUSIONS

In patients with acute ischemic stroke and atrial fibrillation, treatment with NOACs was associated with a combined 5% rate of ischemic embolic recurrence and severe bleeding within 90 days.

PR Interval Prolongation and Cryptogenic Stroke: A Multicenter Retrospective Study

BACKGROUND

Atrial dysfunction or "cardiopathy" has been recently proposed as a mechanism in cryptogenic stroke. A prolonged PR interval may reflect impaired atrial conduction and thus may be a biomarker of atrial cardiopathy. We aim to compare the prevalence of PR interval prolongation in patients with cryptogenic stroke (CS) when compared with known non-cryptogenic non-cardioembolic stroke (NCNCS) subtypes.

METHODS

We used prospective ischemic stroke databases of 3 comprehensive stroke centers to identify patients 18 years or older with a discharge diagnosis of ischemic non-cardioembolic stroke between December 1, 2013 and August 31, 2015. The main outcome was ischemic stroke subtype (CS versus NCNCS). We compared PR intervals as a continuous and categorical variable (<200 milliseconds; ≥200 milliseconds) and other clinical and demographic factors between the 2 groups and used multivariate regression analyses to determine the association between PR interval prolongation and CS.

RESULTS

We identified 644 patients with ischemic non-cardioembolic stroke (224 CS and 420 NCNCS). Patients with CS were more likely to have a PR of 200 milliseconds or greater when compared with those with NCNCS (23.2% versus 13.8%, P = .009). After adjusting for factors that were significant in univariate analyses, a PR of 200 milliseconds or greater was independently associated with CS (odds ratio [OR] 1.70, 95% CI 1.08-2.70). The association was more pronounced when excluding patients on atrioventricular nodal blocking agents (OR 2.64, 95% CI 1.44-4.83).

CONCLUSIONS

A PR of 200 milliseconds or greater is associated with CS and may be a biomarker of atrial cardiopathy in the absence of atrial fibrillation. Prospective studies are needed to confirm this association.

Prediction of Early Recurrent Thromboembolic Event and Major Bleeding in Patients With Acute Stroke and Atrial Fibrillation by a Risk Stratification Schema: The ALESSA Score Study

BACKGROUND AND PURPOSES

This study was designed to derive and validate a score to predict early ischemic events and major bleedings after an acute ischemic stroke in patients with atrial fibrillation.

METHODS

The derivation cohort consisted of 854 patients with acute ischemic stroke and atrial fibrillation included in prospective series between January 2012 and March 2014. Older age (hazard ratio 1.06 for each additional year; 95% confidence interval, 1.00-1.11) and severe atrial enlargement (hazard ratio, 2.05; 95% confidence interval, 1.08-2.87) were predictors for ischemic outcome events (stroke, transient ischemic attack, and systemic embolism) at 90 days from acute stroke. Small lesions (≤1.5 cm) were inversely correlated with both major bleeding (hazard ratio, 0.39; P=0.03) and ischemic outcome events (hazard ratio, 0.55; 95% confidence interval, 0.30-1.00). We assigned to age ≥80 years 2 points and between 70 and 79 years 1 point; ischemic index lesion >1.5 cm, 1 point; severe atrial enlargement, 1 point (ALESSA score). A logistic regression with the receiver-operating characteristic graph procedure (C statistic) showed an area under the curve of 0.697 (0.632-0.763; P=0.0001) for ischemic outcome events and 0.585 (0.493-0.678; P=0.10) for major bleedings.

RESULTS

The validation cohort consisted of 994 patients included in prospective series between April 2014 and June 2016. Logistic regression with the receiver-operating characteristic graph procedure showed an area under the curve of 0.646 (0.529-0.763; P=0.009) for ischemic outcome events and 0.407 (0.275-0.540; P=0.14) for hemorrhagic outcome events.

CONCLUSIONS

In acute stroke patients with atrial fibrillation, high ALESSA scores were associated with a high risk of ischemic events but not of major bleedings.

Abstract WMP62: PR Interval Prolongation and Cryptogenic Stroke: A Multicenter Retrospective Study

Background: Atrial dysfunction or “cardiopathy” has been recently proposed as a mechanism in cryptogenic stroke. A prolonged PR interval may reflect impaired atrial conduction and thus may be a useful biomarker of atrial cardiopathy. We aim to compare the prevalence of PR interval prolongation in patients with cryptogenic stroke (CS) when compared to known non-cryptogenic non-cardioembolic stroke (NCNCS) subtypes.

Methods: We retrospectively analyzed prospective ischemic stroke databases and included consecutive patients between December 1 st , 2013 and August 31 st , 2015 in three comprehensive stroke centers (Rhode Island Hospital, Hartford Hospital, and Tulane University Medical Center). Consecutive patients 18 years or older with a discharge diagnosis of ischemic non-cardioembolic stroke were included. The main outcome was ischemic stroke subtype (CS vs. NCNCS). We compared PR intervals as a continuous and categorical variable (< 200 ms; ≥ 200 ms) and other clinical and demographic factors between the two groups and used multivariate regression analyses including age and other factors deemed significant on univariate analyses to determine the association between PR interval prolongation and CS.

Results: We identified 644 patients with ischemic non-cardioembolic stroke (224 CS and 420 NCNCS). The PR interval was longer in patients with CS vs NCNCS (175.4 ± 35.2 ms vs. 166.5 ± 27.7 p = 0.005). After adjusting for factors that were found to be significant in univariate analyses, a prolonged PR interval was independently associated with CS (Odds Ratio: 1.70; 95% CI 1.08-2.70; p=0.022). The association was more pronounced when excluding patients on atrio-ventricular nodal blocking agents (OR=2.64, 95% CI 1.44-4.83, p=0.002).

Conclusions: A prolonged PR interval is associated with CS and may be a biomarker of atrial cardiopathy in patients with cryptogenic stroke. This association needs to be confirmed in prospective neuro-epidemiological cohorts.

Abstract WP236: Left Atrial Enlargement and Cryptogenic Stroke

Introduction: Despite extensive evaluation, no definite cause is identified in 30-40% of ischemic stroke patients. Biomarkers of atrial dysfunction or “cardiopathy” have been shown to be associated with ischemic stroke risk, a relationship independent of atrial fibrillation. Our aim was to determine the association between left atrial enlargement (LAE) and cryptogenic stroke.

Methods: This was a single center retrospective study using the stoke registry of a comprehensive stroke center. The study was approved by the institution board review. We reviewed medical records of patients admitted with acute ischemic stroke between December 1 st , 2013 and August 31 st , 2015 for demographic data (age and sex) and risk factors (hypertension, hyperlipidemia, coronary artery disease, prior stroke, congestive heart failure, and current smoking status). A vascular neurologist determined stroke subtype and cryptogenic stroke was defined based on the embolic stroke of unknown source (ESUS) criteria. Patients with cardioembolic stroke were excluded and the control group included small vessel disease, large vessel disease and other causes including hypercoagulable states, dissection and drug use. The primary predictor was left atrial (LA) size from 2D echocardiography and LA size was categorized as normal, mild LAE, moderate LAE, and severe LAE using the American Society of Echocardiography Recommendations for chamber quantification.

Results: We identified 236 patients with ischemic stroke; 85 cryptogenic stroke and 151 non-cryptogenic stroke. For the entirety of the group, the mean age was 67 years with 45% males. Patients with cryptogenic stroke were more likely to have moderate to severe LAE when compared to patients with known non-cardioembolic etiology (12.8% vs. 3.2%, p = 0.0061).

Conclusion: Moderate to severe left atrial enlargement, a biomarker of atrial cardiopathy or dysfunction, is more prevalent in patients with cryptogenic stroke than non-cardioembolic strokes of known etiology. Clinical trials are needed to study anticoagulation vs. antiplatelet therapy in patients with cryptogenic stroke and evidence of moderate to severe LAE.

An unusual presentation of classic idiopathic polyarteritis nodosa as acute interstitial nephritis

In the medical literature, there have been few reported cases of classic Polyarteritis Nodosa (cPAN) presenting with acute renal failure (ARF) and, unlike microscopic polyangiitis (MPA), no documentation to our knowledge of cPAN with clinical presentation similar to acute interstitial nephritis. We describe a case of ARF and a clinical picture suggestive of acute interstitial nephritis (AIN). However, renal biopsy of this patient showed acute necrotizing intrarenal vasculitis, suggestive of cPAN. Although no guidelines exist for the most appropriate therapy for patients presenting in this fashion, combination therapy with cyclophosphamide and steroids, in our patient, resulted in clinical improvement and resolution of dialysis-dependent renal failure. These findings suggest the potential for good prognosis in patients with cPAN who present with a presumed diagnosis of AIN and dialysis-dependent ARF.

Diagnostic confirmation of mild traumatic brain injury by diffusion tensor imaging: a case report

Introduction

Traumatic brain injury is a form of acquired brain injury that results from sudden trauma to the head. Specifically, mild traumatic brain injury is a clinical diagnosis that can have significant effects on an individual's life, yet is difficult to identify through traditional imaging techniques.

Case presentation

This is the case of a 68-year-old previously healthy African American woman who was involved in a motor vehicle accident that resulted in significant head trauma. After the accident, she experienced symptoms indicative of mild traumatic brain injury and sought a neurological consultation when her symptoms did not subside. She was initially evaluated with a neurological examination, psychological evaluation, acute concussion evaluation and a third-party memory test using software from CNS Vital Signs for neurocognitive function. A diagnosis of post-concussion syndrome was suggested. Diffusion tensor imaging revealed decreased fractional anisotropy in the region immediately adjacent to both lateral ventricles, which was used to confirm the diagnosis. Fractional anisotropy is a scalar value between zero and one that describes the degree of anisotropy of a diffusion process. These results are indicative of post-traumatic gliosis and are undetectable by magnetic resonance imaging. Our patient was treated with cognitive therapy.

Conclusion

Minor traumatic brain injury is a common injury with variable clinical presentation. The system of diagnosis used in this case found a significant relationship between the clinical assessment and imaging results. This would not have been possible using traditional imaging techniques and highlights the benefits of using diffusion tensor imaging in the sub-acute assessment of minor traumatic brain injury.