Antithrombotic Therapy in the Prevention of Stroke

OVERVIEW

Ischemic stroke is a leading cause of death and disability throughout the world. Antithrombotic therapy, which includes both antiplatelet and anticoagulant agents, is a primary medication of choice for the secondary prevention of stroke. However, the choices vary with the need to incorporate evolving, newer information into the clinical scenario. There is also the need to factor in co-morbid medical conditions as well as the cost ramifications for a particular patient as well as compliance with the regimen. Pertinent Updates: In the acute setting, dual antiplatelet therapy from three weeks to up to three months has become recognized as a reasonable approach for patients with either minor stroke or transient ischemic attack or those with symptoms associated with higher-grade intracranial stenosis. This approach is favored for non-cardioembolic stroke as a cardiogenic mechanism tends to be best managed with attention to the cardiac condition as well as anticoagulant therapy. Risk stratification for recurrent stroke is important in weighing potential risk versus benefits. For example, prolonged dual antiplatelet therapy, with a combination such as aspirin and clopidogrel or aspirin and ticagrelor, tends to have negation of the potential clinical benefit of stroke prevention, over time, by the enhanced bleeding risk. Anticoagulant choices are now impacted by newer agents, initially identified as novel oral anticoagulants (NOACs), which also became associated with "non-vitamin K" agents as they are no longer considered novel. Alternatively, they are now often identified as direct oral anticoagulants (DOACs). They tend to be viewed as superior or non-inferior to warfarin with the caveat that warfarin is still viewed as the agent of choice for stroke prevention in patients with mechanical heart valves.

CONCLUSION

Based upon cumulative information from multiple clinical trials of secondary prevention of stroke, there is an increasing array of approaches in an effort to provide optimal management. Antithrombotic therapy, including in combination with anticoagulant therapy, continues to evolve with the general caveat that "one size does not fit all". In view of this, we desire to provide an evidence-based approach for the prevention of stroke with antithrombotic agents.

Heart-Brain Relationship in Stroke

The patient presenting with stroke often has cardiac-related risk factors which may be involved in the mechanism of the stroke. The diagnostic assessment is predicated on recognition of this potential relationship. Naturally, an accurate history is of utmost importance in discerning a possible cause and effect relationship. The EKG is obviously an important clue as well as it allows immediate assessment for possible cardiac arrhythmia, such as atrial fibrillation, for possible acute ischemic changes reflective of myocardial ischemia, or there may be indirect factors such as the presence of left ventricular hypertrophy, typically seen with longstanding hypertension, which could be indicative of a hypertensive mechanism for a patient presenting with intracerebral hemorrhage. For all presentations in the emergency room, the vital signs are important. An elevated body temperature in a patient presenting with acute stroke raises concern about possible infective endocarditis. An irregular-irregular pulse is an indicator of atrial fibrillation. A markedly elevated blood pressure is not uncommon in both the acute ischemic and acute hemorrhagic stroke setting. One tends to focus on possible cardioembolic stroke if there is the sudden onset of maximum neurological deficit versus the stepwise progression more characteristic of thrombotic stroke. Because of the more sudden loss of vascular supply with embolic occlusion, seizure or syncope at onset tends to be supportive of this mechanism. Different vascular territory involvement on neuroimaging is also a potential indicator of cardioembolic stroke. Identification of a cardiogenic source of embolus in such a setting certainly elevates this mechanism in the differential. There have been major advances in management of acute cerebrovascular disease in recent decades, such as thrombolytic therapy and endovascular thrombectomy, which have somewhat paralleled the advances made in cardiovascular disease. Unfortunately, the successful limitation of myocardial damage in acute coronary syndrome, with intervention, does not necessarily mirror a similar salutary effect on functional outcome with cerebral infarction. The heart can also affect the brain from a cerebral perfusion standpoint. Transient arrhythmias can result in syncope, while cardiac arrest can result in hypoxic-ischemic encephalopathy. Cardiogenic dementia has been identified as a mechanism of cognitive impairment associated with severe cardiac failure. Structural cardiac abnormalities can also play a role in brain insult, and this can include tumors, such as atrial myxoma, patent foramen ovale, with the potential for paradoxical cerebral embolism, and cardiomyopathies, such as Takotsubo, can be associated with precipitous cardioembolic events.

The Role of the ACE2/MasR Axis in Ischemic Stroke: New Insights for Therapy

Ischemic stroke remains the leading cause of neurologically based morbidity and mortality. Current stroke treatment is limited to two classes of FDA-approved drugs: thrombolytic agents (tissue plasminogen activator (tPA)) and antithrombotic agents (aspirin and heparin), which have a narrow time-window (<4.5 h) for administration after onset of stroke symptoms. While thrombolytic agents restore perfusion, they carry serious risks for hemorrhage, and do not influence damage responses during reperfusion. Consequently, stroke therapies that can suppress deleterious effects of ischemic injury are desperately needed. Angiotensin converting enzyme-2 (ACE2) has been recently suggested to beneficially influence experimental stroke outcomes by converting the vasoconstrictor Ang II into the vasodilator Ang 1-7. In this review, we extensively discuss the protective functions of ACE2-Ang (1-7)-MasR axis of renin angiotensin system (RAS) in ischemic stroke.

Overview of Acute Ischemic Stroke Evaluation and Management

Stroke is a major contributor to death and disability worldwide. Prior to modern therapy, post-stroke mortality was approximately 10% in the acute period, with nearly one-half of the patients developing moderate-to-severe disability. The most fundamental aspect of acute stroke management is "time is brain". In acute ischemic stroke, the primary therapeutic goal of reperfusion therapy, including intravenous recombinant tissue plasminogen activator (IV TPA) and/or endovascular thrombectomy, is the rapid restoration of cerebral blood flow to the salvageable ischemic brain tissue at risk for cerebral infarction. Several landmark endovascular thrombectomy trials were found to be of benefit in select patients with acute stroke caused by occlusion of the proximal anterior circulation, which has led to a paradigm shift in the management of acute ischemic strokes. In this modern era of acute stroke care, more patients will survive with varying degrees of disability post-stroke. A comprehensive stroke rehabilitation program is critical to optimize post-stroke outcomes. Understanding the natural history of stroke recovery, and adapting a multidisciplinary approach, will lead to improved chances for successful rehabilitation. In this article, we provide an overview on the evaluation and the current advances in the management of acute ischemic stroke, starting in the prehospital setting and in the emergency department, followed by post-acute stroke hospital management and rehabilitation.

Human placenta mesenchymal stem cell protection in ischemic stroke is angiotensin converting enzyme-2 and masR receptor-dependent

Thromboembolic stroke remains a major cause of neurological disability and death. Current stroke treatments (aspirin, tissue plasminogen activator) are significantly limited by timing and risks for hemorrhage which have driven researchers to explore other approaches. Stem cell‐based therapy appears to be an effective option for ischemic stroke. Besides trans‐differentiation into neural cells, stem cells also provide acute protection via paracrine signaling pathways through which releasing neuroprotective factors. We previously reported that intraperitoneal administration of human placenta mesenchymal stem cell (hPMSC) therapy upon reperfusion significantly protected the brain against middle cerebral artery occlusion (MCAO)‐induced injury. In the present study, we specifically investigated the role of hPMSC‐derived angiotensin converting enzyme‐2 (ACE‐2) in protection of MCAO‐induced brain injury by measurement of brain tissue viability, cerebral blood flow, and neurological score. Here, we report for the first time that hPMSC expressing substantial amount of ACE‐2, which mediates hPMSC protection in the MCAO model. Strikingly, we found that the protective effects of hPMSC in MCAO‐induced brain injury could be attenuated by pretreatment of hPMSCs with MLN‐4760, a specific inhibitor of ACE‐2 activity, or by transfection of hPMSCs with ACE‐2‐shRNA‐lentivirus. The hPMSC‐derived ACE‐2 specific protective mechanism was further demonstrated by administration of PD123319, an Angiotensin type‐2 receptor antagonist, or A779, a MasR antagonist. Importantly, our study demonstrated that the protective effects of hPMSC in experimental stroke are ACE‐2/MasR dependent and this signaling pathway represents an innovative and highly promising approach for targeted stroke therapy.

Emerging Concepts in Vascular Dementia: A Review

OBJECTIVE

Vascular dementia (VaD) is the second most common cause of dementia and a major health concern worldwide. A comprehensive review on VaD is warranted for better understanding and guidance for the practitioner. We provide an updated overview of the epidemiology, pathophysiological mechanisms, neuroimaging patterns as well as current diagnostic and therapeutic approaches.

MATERIALS AND METHODS

A narrative review of current literature in VaD was performed based on publications from the database of PubMed, Scopus and Google Scholar up to January, 2021.

RESULTS

VaD can be the result of ischemic or hemorrhagic tissue injury in a particular region of the brain which translates into clinically significant cognitive impairment. For example, a cerebral infarct in the speech area of the dominant hemisphere would translate into clinically significant impairment as would involvement of projection pathways such as the arcuate fasciculus. Specific involvement of the angular gyrus of the dominant hemisphere, with resultant Gerstman's syndrome, could have a pronounced effect on functional ability despite being termed a "minor stroke". Small vessel cerebrovascular disease can have a cumulate effect on cognitive function over time. It is unfortunately well recognized that "good" functional recovery in acute ischemic or haemorrhagic stroke, including subarachnoid haemorrhage, does not necessarily translate into good cognitive recovery. The victim may often be left unable to have gainful employment, drive a car safely or handle their affairs independently.

CONCLUSIONS

This review should serve as a compendium of updated information on VaD and provide guidance in terms of newer diagnostic and potential therapeutic approaches.

Neurological complications of syncope and sudden cardiac arrest

Syncope is very common and usually comes with enough warning for the person to assume a safer position rather than fall in a potentially dangerous way. Syncope may be associated with pregnancy, for example, but we rarely encounter significant injury related to the potential for an associated fall. In the elderly, however, there are often comorbid factors such as delayed reaction time and other aspects of cognitive impairment, along with gait instability, that can affect the defensive reflexes to the point that brain injury, including subdural or epidural hematoma, is not uncommonly encountered. Sudden syncope without warning can also have both neurological and general physical implications in terms of driving safety, safety operating potentially dangerous equipment or exposure to heights as well as the potential impact for drowning or near-drowning while swimming or taking a bath. Sudden death, from whatever the mechanism, implies cerebral hypoperfusion with the potential consequences of hypoxic-ischemic brain injury.

Evolving Approaches to Antithrombotics in Stroke Prevention and Treatment

The optimization of antithrombotic therapy for acute stroke treatment and secondary prevention is an evolving process based on an increasing array of studies that provide an evidence-based approach. Options have increased dramatically with the release of the non-vitamin K oral anticoagulants and with the results of recent randomized clinical trials designed to assess potential benefits versus risks for patients in an individualized fashion. Recent studies have provided important information to guide choice and dosing of antiplatelet agents as well as the length of treatment. Anticoagulant use is particularly pertinent for stroke prevention in patients at higher risk of atrial fibrillation and may have a place in certain other stroke mechanisms. One important focus of study is the potential benefit of combined antiplatelet and anticoagulant therapy. Options for our patients, when the initial choice of therapy does not demonstrate benefit or is not well tolerated, clearly, are valuable. For example, short-term dual antiplatelet therapy for minor stroke and transient ischemic attack is being adopted, but with the recognition that longer-term combined therapy is not worth the increased risk of bleeding. Alternative antiplatelet choices, such as cilostazol and possibly ticagrelor, may be of benefit for refractory patients and this could affect the decision-making process. This review represents an effort to incorporate the information from more recent stroke prevention and treatment studies with information gleaned from prior studies.

Utilization of the large-bore Penumbra JET 7 reperfusion catheter in thrombectomy for acute ischemic stroke: A single-center experience

BACKGROUND AND PURPOSE

The Penumbra JET 7 reperfusion catheter is used in the revascularization of large vessel occlusions in acute ischemic stroke. Description of its use in clinical practice remains limited. Our purpose is to describe our initial experience with the Penumbra JET 7 reperfusion catheter and to report on its safety and efficacy in different thrombectomy techniques.

MATERIALS AND METHODS

We conducted a retrospective study of 50 patients treated with thrombectomy using the Penumbra JET 7 reperfusion catheter. Mean patient age and admission National Institutes of Health Stroke Scale were 70.6 and 17.76, respectively. The most common sites of vessel occlusion were the M1 segment (72%) followed by distal internal carotid artery (14%). Thrombectomy was performed using the direct aspiration first-pass technique and/or aspiration in conjunction with a stent retriever.

RESULTS

Revascularization was achieved in a total of 44 cases (88%). Successful navigation of the Penumbra JET 7 reperfusion catheter to the occlusion site with clot engagement was achieved in 94% of cases. Mean time from vascular access to revascularization was 31.60 min. No catheter-related complications occurred. Clinical outcome data were collected from 43 patients (86%). Of those patients, 51% achieved good outcome (modified Rankin score of 0-2) at 60 or more days follow-up, 28% had poor outcome (modified Rankin score of 3-5), and 9 patients died (21%).

CONCLUSION

The use of the Penumbra JET 7 reperfusion catheter for treatment of acute ischemic stroke was observed to be safe and effective with appropriate revascularization outcomes in different thrombectomy techniques.

Prevalence of ischemic stroke and atrial fibrillation in young patients with migraine national inpatient sample analysis

OBJECTIVE

To estimate the prevalence of ischemic stroke (IS) and atrial fibrillation (AF) in young patients with migraine and to identify the independent predictors of IS in a large cohort of hospitalized patients.

METHODS

A cohort of patients with migraine with aura (MA) and migraine without aura (MO) was identified from the National Inpatient Sample database for the years 2012 to 2015. Ischemic stroke was identified by the International Classification of Diseases-9-CM codes. Binary logistic regression and Chi-square tests were utilized.

RESULTS

A total number of 834,875 young patients (18-44 years) were included in this study with a mean age of 33 years. The prevalence of IS was 1.3% and was significantly higher in patients with MA (3.7% versus 1.2%, P <0.001). The prevalence of AF was 0.9% and it was significantly higher in patients with MA (1.2% versus 0.8%, P <0.001). Migraine with aura was an independent predictor of IS (OR 3.23, 95% CI 3.05-3.42, P <0.001) and AF (OR 1.63, 95% CI 1.42-1.88, P <0.001). Other predictors of IS were hypertension (OR 2.2, 95% CI 2.12-2.3, P <0.001), diabetes mellitus (DM) (OR 1.37, 95% CI 1.31-1.42, P <0.001), peripheral vascular disease (PVD) (OR 12.08, 95% CI 11.23-12.98, P <0.001) and smoking (OR 1.37, 95% CI 1.31-1.42, P <0.001).

CONCLUSION

In this relatively large study, the overall prevalence of IS in young migraine patients was low at 1.3%. The prevalence of IS and AF was significantly higher in patients with MA. Presence of PVD confers a high risk of IS in young patients with migraine. Migraine aura was observed to be an independent predictor of IS and AF in patients with history of migraine. Optimal control of vascular risk factors in migraine patients appears to be indicated despite the overall low risk.

Cognitive impairment assessment and interventions to optimize surgical patient outcomes

For elderly patients undergoing elective surgical procedures, preoperative evaluation of cognition is often overlooked. Patients may experience postoperative delirium (POD) and postoperative cognitive decline (POCD), especially those with certain risk factors, including advanced age. Preoperative cognitive impairment is a leading risk factor for both POD and POCD, and studies have noted that identifying these deficiencies is critical during the preoperative period so that appropriate preventive strategies can be implemented. Comprehensive geriatric assessment is a useful approach which evaluates a patient's medical, psycho-social, and functional domains objectively. Various screening tools are available for preoperatively identifying patients with cognitive impairment. The Enhanced Recovery After Surgery (ERAS) protocols have been discussed in the context of prehabilitation as an effort to optimize a patient's physical status prior to surgery and decrease the risk of POD and POCD. Evidence-based protocols are warranted to standardize care in efforts to effectively meet the needs of these patients.

Implications of the use of mechanical thrombectomy on outcome in large vessel occlusion following the 2015 landmark trials

BACKGROUND

The effectiveness of mechanical thrombectomy (MT) was demonstrated in five landmark trials published in2015.Mechanical thrombectomy is now standard of care for acute ischemic stroke and has been growing in popularity after publication of landmark trials.

OBJECTIVE

To analyze outcomes and trends of the use of MT and intravenous thrombolysis (IVT) in patients with acute ischemic stroke in US hospitals before and after publication of these trials.

METHODS

Patients discharged with a diagnosis of ischemic stroke between 2012 to 2017 were diagnosed using ICD codes from the National Inpatient Sample. Thereafter, patients given acute stroke treatment were identified using the corresponding procedure codes for IVT and MT. The primary clinical outcomes of in-hospital mortality and disability were then compared between two time periods: 2012-2014 (pre-landmark trials) and 2015-2017 (post-landmark trials). Binary logistic regression and Χ² tests were used for statistical analysis.

RESULTS

A total of 57 675 patients (median age 68.9 years (range 18-90), 50.1% female) were identified with acute procedures. Of these patients, 57.6% were from the post-landmark trials time period. Despite an increased number of cases, the rate of IVT decreased from 84.3% to 75.9% and the rate of IVT+MT decreased from 7.1% to 6.3%. After publication of the pivotal trials in 2015, the rates of MT increased from 8.7% to 17.8%. Significant reductions of in-hospital mortality (7.1% vs 8.7%, p<0.001) and disability (64% vs 66.2%, p<0.001) were noted.

CONCLUSION

The analysis showed a significant increase in the proportion of patients receiving MT after 2015. This has translated into reduction of in-hospital mortality and improvement in disability.

Obstructive sleep apnea intensifies stroke severity following middle cerebral artery occlusion

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) is a sleep disorder caused by transient obstruction of the upper airway and results in intermittent hypoxia, sleep fragmentation, sympathetic nervous system activation, and arousal which can have an adverse effect on cardiovascular disease. It is theorized that OSA might intensify stroke injury. Our goal here was to develop a new model of experimental OSA and test its ability to aggravate behavioral and morphological outcomes following transient brain ischemia/reperfusion.

METHODS

We used a 3D printed OSA device to expose C57BL6 mice to 3 h of OSA (obstructive apnea index of 20 events per hour) for three days. These mice were then subjected to ischemia/reperfusion using the middle cerebral artery occlusion model (MCAO) stroke and examined for overall survival, infarct size and neurological scoring.

RESULTS

We found that OSA transiently decreased respiration and reduced oxygen saturation with bradycardia and tachycardia typical of human responses during apneic events. Brain injury from MCAO was significantly increased by OSA as measured by infarct size and location as well as by intensification of neurological deficits; mortality following MCAO was also increased in OSA animals.

CONCLUSIONS

Our findings suggest that our new model of OSA alters respiratory and cardiovascular physiological functions and is associated with enhanced ischemia/reperfusion mediated injury in our non-invasive, OSA intensified model of stroke.

Abstract TP142: Inpatient Mortality Rates in Endovascular Stenting and Angioplasty of Intracranial Vertebral and Basilar Arteries

Objective: To compare inpatient mortality rates in patients who underwent intracranial endovascular stenting and/or angioplasty of the vertebral artery or basilar artery by analyzing data from the National inpatient sample database (2012-2015).

Methods: We extracted data utilizing ICD-9 diagnosis codes for occlusion and stenosis of vertebral artery with or without stroke (433.20, 433.21) and occlusion and stenosis of basilar artery with or without stroke (433.00, 433.01). The cohort included total of 201 patients. Binary logistic regression and Chi-square tests were utilized for data analysis.

Results: A total number of 201 patients underwent either intracranial angioplasty alone or stenting with or without angioplasty for either vertebral or basilar artery stenosis. Male patients were predominant (74%). The majority were 51 to 75 years of age (76.1%). 55% of the patients had stenosis of the basilar artery, 45% had vertebral artery stenosis. The majority of patients underwent stenting with or without angioplasty (69%); 47% had basilar stenting and 53% had vertebral stenting. The common co-morbidities observed were hypertension (84%), diabetes mellitus (37%), peripheral vascular disease (20%) and obesity (14%). The overall mortality rate in this cohort was 17.4%. The mortality rate was significantly higher in patients with basilar artery stenosis when compared with vertebral artery stenosis regardless of type of procedure performed (24% vs 9%, P = 0.004). The mortality during hospitalization was not significantly affected by the type of procedure (angioplasty vs stenting with or without angioplasty), or by the aforementioned comorbidities. The significant predictor of mortality was basilar artery stenosis (OR 2.87, 95% CI 1.18-6.98, P =0.02).

Conclusion: The overall mortality in this cohort of patients who underwent angioplasty vs stenting with or without angioplasty for basilar or vertebral intracranial artery stenosis was 17.4%. Mortality rate was significantly higher in patients with basilar artery stenosis (24%) compared to those with vertebral artery stenosis (9%). The type of procedure performed (angioplasty vs stenting with or without angioplasty) had no significant statistical impact.

Factors Associated with Inpatient Mortality after Intracerebral Hemorrhage: Updated Information from the United States Nationwide Inpatient Sample

BACKGROUND

To use a nationwide database of hospital admissions to assess for trends in inpatient mortality from acute spontaneous intracerebral hemorrhage as well as associated potentially contributing factors.

METHODS

Adults with intracerebral hemorrhage in the US National Inpatient Sample database from 2012 to 2015 were included in this study. We assessed for mortality rate as well as potential impact of various comorbidities and demographic factors such as ethnicity and median house hold income on inpatient mortality rate.

RESULTS

A total of 47,700 patients were identified with a mean age of 68 years. The overall mortality rate was 24%. Hypertension was the commonest comorbidity (84%) followed by diabetes mellitus (28%). Positive associated factors for mortality rate were coagulopathy (OR 1.28, 95% CI 1.19-1.38, P < .001), female gender (OR 1.12, 95% CI 1.08-1.17, P < .001), and congestive heart failure (OR 1.16, 95% CI 1.08-1.24, P < .001). Age greater than 75 was also associated with higher mortality (P < .001). Factors associated with reduced mortality were hypertension (OR .76, 95% CI .72-0.81, P < .001), hypothyroidism (OR .87, 95% CI .81-.93, P < .001) and obesity (OR .64, 95% CI .59-.69, P < .001).

CONCLUSIONS

The inpatient mortality of 24% represents a decline when compared to previous years. Attention to the associated factors with mortality, that we report, could have some potential impact on management. Of interest, we found support for obesity paradox in which obesity may have an actual salutary effect on vascular disease outcome. Our observed paradoxical effects, not only for obesity, but also hypertension and hypothyroidism, warrant further study.

The Relationship Between Obstructive Sleep Apnea and Ruptured Intracranial Aneurysms

STUDY OBJECTIVES

The role of obstructive sleep apnea (OSA) in the overall outcome of ruptured intracranial aneurysms (RIAs) is unknown. We have investigated the role of OSA in overall outcome of RIAs.

METHODS

Data from 159 consecutive patients were retrospectively reviewed. A chi-square test and regression analysis were performed to determine the significant difference. A value of P < .05 was considered significant.

RESULTS

The prevalence of OSA in RIAs was fivefold higher in the nonaneurysm patient group, P = .002. The number of patients with hypertension (P < .0001), body mass index ≥ 30 (P < .0001), hyperlipidemia (P = .018), chronic heart disease (P = .002) or prior ischemic stroke (P = .001) was significantly higher in the OSA group. Similarly, the number of wide-neck aneurysms (P < .0001) and aneurysm > 7 mm (P = .004), poor Hunt and Hess grade IV-V (P = .005), vasospasms, (P = .03), and patients with poor Modified Rankin Scale scores (3-6) was significantly higher in the OSA group (P < .0001). Interestingly, for the first time in univariate (P = .01) and multivariate (P = .003) regression analysis, OSA was identified as an individual predictor of unfavorable outcome of RIAs. In addition, hypertension (P = .04), smoking (P = .049), chronic heart disease (P = .01), and Hunt and Hess grade IV-V (P = .04) were revealed as predictors of poor outcome of RIAs.

CONCLUSIONS

This is a novel study to determine the association between OSA and ruptured cerebral aneurysm in terms of comorbidities, size of aneurysm, severity of symptoms, and outcomes after treatment. In addition, for the first time, OSA is identified as a positive predictor of unfavorable outcome of RIAs.

Frontotemporal Dementia

Frontotemporal dementia (FTD) is a not-uncommon explanation for progressive cognitive deficit in patients who often have a genetic susceptibility for such a neurodegenerative process. However, FTD does not seem to identify one particular pathogenetic mechanism but rather a spectrum of pathologies with particular predilection for the frontal and temporal lobes of the brain. There have been various subcategorizations of this form of dementia that have a tendency to be of earlier onset than typical Alzheimer disease and heralded by behavioral or communication manifestations. There is a behavioral variant and a language variant, referred to as primary progressive aphasia.

A cute verbal dyspraxia, a rare presentation in multiple sclerosis: a case report with MRI localization

C ortical speech disorders rarely occur in multiple sclerosis (MS). We report a patient with relapsing-remitting MS, who presented with acute verbal dyspraxia. Magnetic resonance imaging (MRI) demonstrated an acute T2/Flair hyperintense, primarily white matter lesion underlying the middle third of the inferior frontal gyrus. The verbal dyspraxia cleared beginning 48 hours after the initiation of iv dexamethasone. Follow-up MRI demonstrated qualitative and quantitative diminution of the hyperintensity. This is the first report of a clinically definite MS patient with acute verbal dyspraxia. Moreover, there was a suggestive localization of verbal praxis to Brodmann areas 44/45.

WEST NILE VIRUS MENINGO-ENCEPHALITIS: POSSIBLE SEXUAL TRANSMISSION

PURPOSE

We report a previously healthy middle aged woman who developed West Nile virus meningo-encephalitis within two weeks of unprotected vaginal intercourse with her husband.

SUBJECT

This patient's husband had serologically confirmed West Nile virus infection manifested by a flu-like illness and rash with the sexual contact one day before the onset of his symptoms.

RESULT

This well documented neuroinvasive West Nile virus infection in our patient was within the incubation period of transmission and there was no reported mosquito bite exposure.

CONCLUSION

The timeframe of infection raises the possibility that her illness was sexually transmitted.

A pilot study: portable out-of-center sleep testing as an early sleep apnea screening tool in acute ischemic stroke

INTRODUCTION

Prompt diagnosis of obstructive sleep apnea (OSA) after acute ischemic stroke (AIS) is critical for optimal clinical outcomes, but in-laboratory conventional polysomnograms (PSG) are not routinely practical. Though portable out-of-center type III cardiopulmonary sleep studies (out-of-center cardiopulmonary sleep testing [OCST]) are widely available, these studies have not been validated in patients who have recently suffered from AIS. We hypothesized that OCST in patients with AIS would yield similar results when compared to conventional PSG.

METHODS

Patients with AIS had simultaneous type III OCST and PSG studies performed within 72 hours from symptom onset. The accuracy of OCST was compared to PSG using: chi-square tests, receiver operatory characteristic curves, Bland-Altman plot, paired Student's t-test/Wilcoxon signed-rank test, and calculation of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV).

RESULTS

Twenty-one out of 23 subjects with AIS (age 61±9.4 years; 52% male; 58% African-American) successfully completed both studies (9% technical failure). Nearly all (95%) had Mallampati IV posterior oropharynx; the mean neck circumference was 16.8±1.6 in. and the mean body mass index (BMI) was 30±7 kg/m(2). The apnea hypopnea index (AHI) provided by OCST was similar to that provided by PSG (19.8±18.0 vs 22.0±22.7, respectively; P=0.49). On identifying subjects by OCST with an AHI ≥5 on PSG, OCST had the following parameters: sensitivity 100%, specificity 85.7%, PPV 93%, and NPV 100%. On identifying subjects with an AHI ≥15 on PSG, OCST parameters were as follows: sensitivity 100%, specificity 83.3%, PPV 81.8%, and NPV 100%. Bland-Altman plotting showed an overall diagnostic agreement between OCST and PSG modalities for an AHI cutoff >5, despite fine-grained differences in estimated AHIs.

CONCLUSION

Compared with PSG, OCST provides similar diagnostic information when run simultaneously in AIS patients. OCST is a reliable screening tool for early diagnosis of OSA in AIS patients.

Perioperative stroke

It is increasingly recognized that one can identify a higher risk patient for perioperative stroke. The risk of stroke around the time of operative procedures is fairly substantial and it is recognized that patients initially at risk for vascular events are those most likely to have this risk heightened by invasive procedures. Higher risk patients include those of advanced age and there is a cumulative risk, over time, of coexistent hypertension, atherosclerosis, diabetes mellitus, cardiac disease and clotting disorders. There are a number of possible mechanisms associated with the procedure (e.g., preoperative hypercoagulability, holding of antithrombic therapy at the time of the procedure and cardiac arrhythmia) that can promote a thrombo-embolic event. Examples of these include: direct mechanical trauma to extracranial vessels related to operations on the head and neck; and vascular injury as a consequence of vascular and innovative endovascular procedures affecting the cerebral circulation (e.g., carotid endarterectomy, extracranial or intracranial angioplasty with stenting, and use of the MERCI clot retrieval device), as well as various endovascular methods that have been developed to obliterate cerebral aneurysms and arteriovenous malformations as an alternative to surgical clipping and surgical resection, respectively.

Stiff person syndrome

Recognizing stiff person syndrome is clinically important. It is uncommon, characterized by body stiffness associated with painful muscle spasms, and varies in location and severity. It is subdivided into stiff trunk versus stiff limb presentation, and as a progressive encephalomyelitis. Stiff person-type syndrome also reflects a paraneoplastic picture. Most patients demonstrate exaggerated lumbar lordosis. Roughly 60% of patients have antiglutamic acid decarboxylase antibodies in the blood and the cerebrospinal fluid. The differential diagnosis includes many severe conditions. There are reports of response to muscle relaxants, immunosuppressants, intravenous gamma globulin, plasma exchange, a number of anticonvulsants, and botulinum toxin.

MRS findings in a patient with juvenile-onset Alexander's leukodystrophy

Alexander's leukodystrophy is a rare cerebral white matter disorder with an onset that can be infantile, juvenile, or occur in the adult years. It is thought to be demyelinative, but the pathogenesis is ill-defined. We report a 24-year-old woman with juvenile-onset Alexander disease, of 12 years duration, who underwent magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) serially as part of her care. The patient's latest MRI showed periventricular-increased signal intensity on T2 and fluid attenuation and inversion recovery sequences, which appeared stable when compared to her first study seven years ago. MRS revealed an elevated choline/creatine ratio with relative suppression of the n-acetyl aspartate peak, also similar to her previous MRS findings. MRS also showed elevation of myoinositol levels, best demonstrated with the short echo-time spectra. These findings support the primarily demyelinative characteristics of this leukodystrophy and may provide a surrogate marker of disease progression, as well as a potential response to therapeutic intervention when this becomes available.

Ischemic stroke: emergencies and management

The past 40 years have seen the evolution of acute ischemic stroke management from unproven therapies du jour, such as steroids, heparin for stroke in evolution, and hypervolemic-hemodilution, to more of a scientific basis for our decision-making process. This evolution is directly related to the advancements in imaging of stroke. It is also related to carefully designed, controlled clinical trials of potential therapies, which have led to the recognition of the benefits of thrombolytic therapy in the acute setting but have also caused confusion and frustration over the lack of benefit for potential neuroprotective agents that once seemed promising.

Stem cell factor and granulocyte colony-stimulating factor reduce β-amyloid deposits in the brains of APP/PS1 transgenic mice

INTRODUCTION

Alzheimer's disease (AD) is widely recognized as a serious public health problem and heavy financial burden. Currently, there is no treatment that can delay or stop the progressive brain damage in AD. Recently, we demonstrated that stem cell factor (SCF) in combination with granulocyte colony-stimulating factor (G-CSF) (SCF+G-CSF) has therapeutic effects on chronic stroke. The purpose of the present study is to determine whether SCF+G-CSF can reduce the burden of β-amyloid deposits in a mouse model of AD.

METHODS

APP/PS1 transgenic mice were used as the model of AD. To track bone marrow-derived cells in the brain, the bone marrow of the APP/PS1 mice was replaced with the bone marrow from mice expressing green fluorescent protein (GFP). Six weeks after bone marrow transplantation, mice were randomly divided into a saline control group and a SCF+G-CSF-treated group. SCF in combination with G-CSF was administered subcutaneously for 12 days. Circulating bone marrow stem cells (CD117+ cells) were quantified 1 day after the final injection. Nine months after treatment, at the age of 18 months, mice were sacrificed. Brain sections were processed for immunohistochemistry to identify β-amyloid deposits and GFP expressing bone marrow-derived microglia in the brain.

RESULTS

Systemic administration of SCF+G-CSF to APP/PS1 transgenic mice leads to long-term reduction of β-amyloid deposition in the brain. In addition, we have also observed that the SCF+G-CSF treatment increases circulating bone marrow stem cells and augments bone marrow-derived microglial cells in the brains of APP/PS1 mice. Moreover, SCF+G-CSF treatment results in enhancement of the co-localization of bone marrow-derived microglia and β-amyloid deposits in the brain.

CONCLUSIONS

These data suggest that bone marrow-derived microglia play a role in SCF+G-CSF-induced long-term effects to reduce β-amyloid deposits. This study provides insights into the contribution of the hematopoeitic growth factors, SCF and G-CSF, to limit β-amyloid accumulation in AD and may offer a new therapeutic approach for AD.

Interferon (IFN)-ß1a and IFN-ß1b Block IFN-?-Induced Disintegration of Endothelial Junction Integrity and Barrier

Recent clinical trials indicate the efficacy of interferon (IFN)-beta 1b in reducing relapse rate in relapsing-remitting multiple sclerosis (MS), whereas a surge of IFN-gamma precedes and provokes acute relapses. Disruption of the cerebral endothelial barrier and transendothelial migration of inflammatory cell migration into the brain play a significant role in pathogenesis of MS and may be driven by this surge in IFN-gamma. However, the molecular mechanisms underlying the beneficial effects of IFN-beta 1b against the deleterious effects of IFN-gamma on the barrier formed by the junctional proteins remain to be characterized. The authors investigated the effects of IFN-beta 1b, IFN-beta 1a, and IFN-gamma on the integrity of two endothelial junctional proteins, occludin and vascular endothelial-cadherin (VE-cadherin). Human umbilical vein endothelial cell (HUVEC) layers were treated with IFN-beta 1b, IFN-beta 1a, IFN-gamma, IFN-beta 1b plus IFN-gamma, or IFN-beta 1a plus IFN-gamma. IFN-beta 1b, IFN-beta 1a, and IFN-gamma effects on occludin and VE-cadherin integrity and electrical resistance were assessed by Western blotting and immunofluorescence. IFN-gamma significantly reduced occludin expression and produced gaps in endothelial monolayers. VE-cadherin expression was decreased to a lesser extent in endothelial cells exposed to IFN-gamma. IFN-beta 1b significantly attenuated the IFN-gamma-induced decrease in occludin and VE-cadherin expression. The protective effects of IFN-beta 1a on IFN-gamma-treated endothelial cells were similar to those of IFN-beta 1b. IFN-gamma also significantly reduced endothelial monolayer electrical resistance; this effect was blocked by either IFN-beta 1a or IFN-beta 1b. IFN-beta 1a and IFN-beta 1b effectively prevent the IFN-gamma-induced disintegration of the endothelial tight junctions and sustain barrier against the effects of IFN-gamma. The protective effects of IFN-beta on occludin and VE-cadherin stability appear to represent molecular mechanisms for the therapeutic effects of the IFN-beta on blood brain barrier in MS.

Memory complaints and dementia

With people having the luxury of living longer there is an increasing epidemic of dementia throughout the world. It is important to distinguish true dementia from the not-unexpected loss of mental acuity as people age. This latter process has been termed "benign forgetfulness of senescence." We are all probably susceptible to memory loss if we live long enough. Progressive cognitive impairment to a clinically significant degree, with no obvious identifiable factor, such as a metabolic disturbance, drug intoxication, or medication effect, probably indicates a dementing illness, however.

Multiple sclerosis: clinical features, pathophysiology, neuroimaging and future therapies

Multiple sclerosis (MS) is a common immune-mediated progressive neurodegenerative disease of the CNS that typically manifests with periods of disease activity followed by intervals of remission. The etiology of MS remains unknown; however, existing evidence indicates that MS is a ‘whole-brain disease’ that is driven by a potent immune response against CNS antigen(s), particularly myelin peptide antigens. The immunopathogenesis of MS includes both the cell- and humorally-mediated arms of the immune system. Genetic and environmental factors play important roles in the development of MS. Application of various neuroimaging techniques to the world of MS have expanded our knowledge concerning its pathogenesis and assist us in the more accurate diagnosis of MS versus its imitators. Current treatments target acute attacks and aim to reduce future clinical relapses. A summary of the potential future therapies for MS is presented.

Movement disorders

Abnormal involuntary movements are major features of a large group of neurologic disorders, some of which are neurodegenerative and pose a significant diagnostic and treatment challenge to treating physicians. This article presents a concise review of clinical features, pathogenesis, epidemiology, and management of seven of the most common movement disorders encountered in a primary care clinic routinely. The disorders discussed are Parkinson disease, essential tremor, restless legs syndrome, Huntington disease, drug-induced movement disorder, Wilson disease, and Tourette syndrome.

Antiphospholipid antibodies: paradigm in transition

OBJECTIVES

This is a critical review of anti-phospholipid antibodies (aPL). Most prior reviews focus on the aPL syndrome (APS), a thrombotic condition often marked by neurological disturbance. We bring to attention recent evidence that aPL may be equally relevant to non-thrombotic autoimmune conditions, notably, multiple sclerosis and ITP.

ORGANIZATION

After a brief history, the recent proliferation of aPL target antigens is reviewed. The implication is that many more exist. Theories of aPL in thrombosis are then reviewed, concluding that all have merit but that aPL may have more diverse pathological consequences than now recognized. Next, conflicting results are explained by methodological differences. The lupus anticoagulant (LA) is then discussed. LA is the best predictor of thrombosis, but why this is true is not settled. Finally, aPL in non-thrombotic disorders is reviewed.

CONCLUSION

The current paradigm of aPL holds that they are important in thrombosis, but they may have much wider clinical significance, possibly of special interest in neurology.

Potential value of quantitative analysis of cerebral PET in early cognitive decline

BACKGROUND

In patients diagnosed with Alzheimer's disease, positron emission tomography brain scans can have characteristic hypometabolic patterns that strongly support this diagnosis, but this pattern is often subtle or absent in early stages. A sensitive and objective method for detection of positron emission tomography abnormalities may have value in early detection of Alzheimer's disease.

METHODS

A 2-fluoro-2-deoxy-D-glucose positron emission tomography scans from cognitively impaired patients (n = 43) were compared individually to 28 normal controls using statistical parametric mapping, hypometabolic regions visualized, and clinically correlated. The objective SPM results were compared to the official Nuclear Medicine report based upon subjective interpretation criteria.

RESULTS

A total of 22/43 had abnormalities per the Nuclear Medicine physician, while 21/43 appeared normal. The objective analysis detected abnormalities in 41/43 participants, including 19 of 21 that appeared normal. In these 19, 8 had findings consistent with early Alzheimer's disease.

CONCLUSION

Objective analysis of positron emission tomography brain scans may extend the ability to detect early brain abnormalities in patients with cognitive decline.

Painful brachial plexopathies in SEPT9 mutations: adverse outcome related to comorbid states

Hereditary neuralgic amyotrophy (HNA), an autosomal dominant disorder associated with SEPT9 mutation located on chromosome 17q25, causes recurrent painful weakness with sensory disturbances in a brachial distribution. We present electrophysiological, clinical phenotype, and molecular genetic data of three members from a family with HNA with the C262T SEPT9 mutation. The degree of motor weakness and recovery is variable within this family. Severity and recovery from motor deficits may have been a function of comorbid medical conditions. To our knowledge, this is the first report to confirm SEPT9 mutation in a family with suspected HNA.

Circuitous embolic hemorrhagic stroke: carotid pseudoaneurysm to fetal posterior cerebral artery conduit: a case report

Introduction

The cervical internal carotid artery (ICA) is susceptible to injury through various mechanisms, including dissection, which can lead to pseudoaneurysm formation. Pathological processes affecting the ICA, in association with an ipsilateral fetal posterior cerebral artery (PCA), resulting in parieto-occipital strokes are rarely reported.

Case Presentation

We present a patient with a left PCA territory, presumably embolic, stroke with early hemorrhagic transformation. The identified nidus of the embolus was a carotid artery pseudoaneurysm. Manifestations included right homonymous hemianopsia with right hemiparesis and hemisensory loss.

Conclusion

Our case is unique, and of clinical interest, because it illustrates both the potential anterior-posterior circulation conduit provided by a fetal origin PCA as well as the apparent early hemorrhagic transformation of embolic infarcts that can lead to further confusion from a mechanistic standpoint.

Combination therapy with interferon beta-1a and doxycycline in multiple sclerosis: an open-label trial

OBJECTIVE

To evaluate the efficacy, safety, and tolerability of combination therapy with intramuscular interferon beta-1a and oral doxycycline, a potent inhibitor of matrix metalloproteinases, in patients with relapsing-remitting multiple sclerosis (RRMS) having breakthrough disease activity.

DESIGN

Open-label, 7-month trial.

SETTING

Louisiana State University Health Sciences Center, Shreveport.

PATIENTS

Fifteen patients with RRMS taking interferon beta-1a with breakthrough disease activity took doxycycline for 4 months. Patients underwent monthly neurologic examination, magnetic resonance imaging of the brain using triple-dose gadolinium, and safety blood work.

INTERVENTIONS

Ongoing treatment with intramuscular interferon beta-1a plus oral doxycycline, 100 mg daily, for 4 months.

MAIN OUTCOME MEASURES

The primary end point was gadolinium-enhancing lesion number change, and the secondary end points were relapse rates, safety and tolerability of the combination of interferon beta-1a and doxycycline in patients with MS, Expanded Disability Status Scale score, serum matrix metalloproteinase-9 levels, and transendothelial migration of monocytes exposed to serum from patients with RRMS.

RESULTS

Combination of doxycycline and interferon beta-1a treatment resulted in reductions in contrast-enhancing lesion numbers and posttreatment Expanded Disability Status Scale values (P < .001 for both). Only 1 patient relapsed. Multivariate analyses indicated correlations between decreased serum matrix metalloproteinase-9 levels and enhancing lesion activity reduction. Transendothelial migration of monocytes incubated with serum from patients with RRMS undergoing combination therapy was suppressed. Adverse effects were mild; no adverse synergistic effects of combination therapy or unexpected adverse events were reported.

CONCLUSIONS

Combination of intramuscular interferon beta-1a and oral doxycycline treatment was effective, safe, and well tolerated. Controlled clinical trials in larger cohorts of patients with MS are needed to evaluate the efficacy and tolerability of this combination. Trial Registration clinicaltrials.gov Identifier: NCT00246324

Clinical and neuroimaging correlates of antiphospholipid antibodies in multiple sclerosis: a preliminary study

Background

The presence of antiphospholipid antibodies (APLA) in multiple sclerosis (MS) patients has been reported frequently but no clear relationship between APLA and the clinical and neuroimaging features of MS have heretofore been shown. We assessed the clinical and neuroimaging features of MS patients with plasma APLA.

Methods

A consecutive cohort of 24 subjects with relapsing-remitting (RR) MS were studied of whom 7 were in remission (Rem) and 17 in exacerbation (Exc). All subjects were examined and underwent MRI of brain. Patients' plasma was tested by standard ELISA for the presence of both IgM and IgG antibodies using a panel of 6 targets: cardiolipin (CL), β2 glycoprotein I (β2GPI), Factor VII/VIIa (FVIIa), phosphatidylcholine (PC), phosphatidylserine (PS) and phosphatidylethanolamine (PE).

Results

In exacerbation up to 80% of MS subjects had elevated titers of IgM antibodies directed against the above antigens. However, in remission, less than half of MS patients had elevated titers of IgM antibodies against one or more of the above antigens. This difference was significant, p < 0.01, for all 6 target antigens. Interestingly, none of the MS patients had elevated plasma titers of IgG against any of the target antigens tested. Correlation analysis between MRI enhancing lesions and plasma levels of APLA revealed high correlation for aPC, aPS and aFVIIa (p ≤ 0.0065), a trend for aPE and aCL (p = 0.056), and no correlation for aβ2GP1. The strongest correlation was for aFVIIa, p = 0.0002.

Conclusion

The findings of this preliminary study show that increased APLA IgM is associated with exacerbations of MS. Currently, the significance of this association in pathogenesis of MS remains unknown. However, systematic longitudinal studies to measure APLA in larger cohorts of patients with relapsing-remitting MS, particularly before and after treatment with immunomodulatory agents, are needed to confirm these preliminary findings.

Demonstration of significant resolution of cerebral sino-venous thrombosis associated with intravenous recombinant tissue plasminogen activator

BACKGROUND

Cerebral sino-venous thrombosis (CVT) is commonly treated with anticoagulant therapy. There are reports of response to endovascular thrombolysis with or without mechanical aspiration in patients with clinical deterioration.

CASE

We present a 29-year-old man with acute onset of severe headache, found to have extensive CVT by magnetic resonance venography (MRV). His atypical presentation led to cerebral angiography that was complicated by global aphasia and right hemiparesis from left middle cerebral artery distribution ischemia. He received intravenous rt-PA (recombinant tissue plasminogen activator) within an hour of the procedure followed, 24 hours later, by intravenous heparin infusion with significant clinical improvement. The headache severity and CVT, on follow-up MRV, resolved significantly within 2 days.

CONCLUSIONS

We demonstrate clinical and neuroimaging response to systemic rt-PA in CVT. Thrombolysis may have a role in CVT management with an extended therapeutic window.

Transient ischemic attack in a patient with absent carotid circulation and dilated vertebrobasilar vessels

Internal carotid artery (ICA) agenesis is a rare vascular anomaly that, in combination with occlusion of the contralateral ICA, produces significant strain on the posterior circulation for collateral flow. We report a patient who presented with transient ischemic attack and was found to have congenital ICA agenesis and contralateral ICA occlusion with cerebral perfusion maintained through dilated vertebrobasilar circulation.