American Heart Association

Monthly Archives: May 2020

Small Vessel Disease: Collaterals’ Enemy

Elena Zapata-Arriaza, MD
@ElenaZaps

Lin MP, Brott TG, Liebeskind DS, Meschia JF, Sam K, Gottesman RF. Collateral Recruitment Is Impaired by Cerebral Small Vessel Disease. Stroke. 2020;51:1404–1410.

Small vessel disease (SVD) is clearly related to increased stroke risk and worse functional outcome. However, the effect of mentioned SVD on the vasodilatory capacity of arteriole and microvasculature for collaterals recruitment during an acute stroke scenario is unclear. Lin and colleagues performed a study to asses SVD effect on collaterals development in acute stroke setting.

For this study, consecutive patients with middle cerebral artery or internal carotid artery occlusion presenting within 6 hours after stroke symptom onset who underwent thrombectomy from 2012 to 2017 were included. The primary outcome was poor collateral flow (assessed on baseline computed tomographic angiography). Markers of chronic SVD on brain magnetic resonance imaging were rated for the extent of white matter hyperintensities, enlarged perivascular spaces, chronic lacunar infarctions and cerebral microbleeds using the Standards for Reporting Vascular Changes on Neuroimaging criteria. Severity of SVD was quantified by adding the presence of each SVD feature, with a total possible score of 0 to 4; each SVD type was also evaluated separately.

Functional Stroke Mimics: How Hard Is It to Say This Is Not a Stroke?

Victor J. Del Brutto, MD

Popkirov S, Stone J, Buchan AM. Functional Neurological Disorder: A Common and Treatable Stroke Mimic. Stroke. 2020;51:1629–1635.

Since the work of Jean-Martin Charcot in the 19th century on functional neurological disorders (called “hysteria”), neurologists have developed a variety of examination skills capable of discerning between organic and non-organic causes of neurological symptoms. Functional neurological disorders may manifest as non-epileptic seizures, chronic abnormal movement disorders, and certainly as acute focal neurological deficits prompting the activation of a rapid stroke evaluation aimed to identify candidates for reperfusion therapies. In fact, functional neurological deficits are common stroke mimics frequently presenting as lateralized limb weakness, sensory changes, or speech disturbances.

As stroke neurologists, we rely on clinical scales (i.e., the National Institutes of Health Stroke Scale) and a variety of neuroimaging techniques to make time-sensitive therapeutic decisions. Nevertheless, none of the above are entirely useful to identify functional disorders, thus underscoring the importance of the clinical examination in acute stroke care. In the May issue of Stroke, Popkirov and colleagues bring us a topical review on the diagnosis of functional disorders during the acute evaluation of patients with suspected stroke. Key points of this review include:

– Stereotypical biases based on age, sex, psychiatric comorbidities, or social background are not good predictors of functional disorders at the individual patient level and frequently lead to misdiagnosis. 

– Bedside tests focused on inconsistencies between voluntary and involuntary movements (i.e., Hoover’s sign, hip abductor sign, facial lip pulling) or non-physiological patterns of weakness (i.e., drift without pronation, give-away weakness, inverse pyramidal pattern) have shown to be specific and reliable techniques to identify functional motor weakness (Figure). Generally, sensory signs are less reliable than motor testing.

Figure. Positive clinical signs of functional neurological disorder.
Figure. Positive clinical signs of functional neurological disorder. 

– Speech disorders (i.e., dysarthria, aphasia) in isolation are rare stroke presentations. Functional speech disorders can be recognized by inconsistencies such as aphonia with normal sound production prompted by cough, dysarthria without dysphagia, or non-physiological agrammatism (“baby talk”) rather than the telegraphic speech characteristic of Broca’s aphasia.

Practice Makes Perfect: Article Commentary on “Improving Stroke Care in Times of the COVID-19 Pandemic Through Simulation: Practice your Protocols!”

Muhammad Rizwan Husain, MD, and Muhammad Taimoor Khan, MD
@RIZWANHUSAINMD

Kurz MW, Ospel JM, Kurz KD, Goyal M. Improving Stroke Care in Times of the COVID-19 Pandemic Through Simulation: Practice Your Protocols! Stroke. 2020.

The COVID-19 pandemic portends a risk to healthcare staff dealing with acute stroke emergencies, and many institutions have developed new protocols to help reduce exposure. On a typical day, acute stroke management progresses through a well-defined algorithm, developed by institutions to provide rapid and timely intravenous thrombolysis and mechanical thrombectomy (MT), with healthcare providers having their own well-defined roles. The COVID-19 pandemic has now required enforcement of strict infection control practices such as use of PPE, methods to minimize exposure to patients and staff during imaging and transport and while providing thrombolytic treatment or MT. However, despite these new well-defined protocols and standards of infection control safety in place, there is still a risk of exposure to healthcare workers, who might not be used to adapting quickly to a new system of management, again risking unwarranted exposure, which further leads to increased anxiety among the front line staff.

In this article, the authors describe how practice simulations catered to help staff adapt to the new standards have helped streamline the process of acute stroke emergencies, reduce staff anxiety and, at the same time, identify potential unknown sources of exposure, as well.

Stroke vs COVID-19: A World Fight

Elena Zapata-Arriaza, MD
@ElenaZaps

Zhao J, Li H, Kung D, Fisher M, Shen Y, Liu R. Impact of the COVID-19 Epidemic on Stroke Care and Potential Solutions. Stroke. 2020.

Since the first COVID-19 case was reported in December 2019 in Wuhan, China, the magnitude of this global pandemic, unimaginable at first, has invaded our daily routine and our professional work, displacing any other pathology to a secondary level. As of Saturday, May 9, 2020 at 1:36 p.m., the global number of infected is 3.94 million people and 275,000 deaths, with a spatial dispersion that increasingly affects more countries. Given its ease of transmission (drops when coughing, speaking, direct contact), we are facing a highly contagious virus capable of saturating the health systems, preventing proper management of time-dependent pathologies such as ischemic stroke. Zhao J et al. aimed to demonstrate COVID-19 impact on stroke care. For this purpose, the authors collected data from the Big Data Observatory Platform for Stroke of China (BOSC), formed by 280 hospitals across China. In addition, they designed a survey to investigate major changes in stroke care during the COVID-19 outbreak.

After performing a retrospective and simple descriptive study, the authors found a drop of 26.7% and 25.3% (p<0.001), respectively, in thrombolysis and thrombectomy cases, in February 2020 as compared to February 2019. In 2020, hospital admissions related to stroke dropped by nearly 40%, due to the reduction in stroke care capacity in the majority of hospitals. In stroke care centers, the majority of them stopped completely or partially their efforts in stroke education for the public, with no difference in the patterns of changes between COVID-19 and non-COVID-19 designated hospitals. Among potential causes of observed changes, the authors found that patients or patients’ families not coming to the hospital was likely the most important factor affecting reduced hospital admission rate, and reduced thrombolysis and thrombectomy cases. Deficiencies in stroke awareness, lack of adequate transportation methods, and the COVID-19 screening process were considered as important factors with a direct impact on stroke care and door-to-needle and door-to-groin times. Finally, the authors offer recommendations to improve stroke care in affected countries.

Stroke Care During World War COVID

Victor J. Del Brutto, MD

Sheth SA, Wu T-C, Sharrief A, Ankrom C, Grotta JC, Fisher, M, et al. Early Lessons From World War COVID: Reinventing Our Stroke Systems of Care. Stroke. 2020.

The past century began with devastating world wars that resulted in immense loss of life and left many countries in ruins and the rest impoverished. These global conflicts not only created negative impacts, but also triggered constructive responses in humanity fueled by the elation for surviving the disaster. The latter resulted in postwar times dominated by the development of society, expansion of economy, and the revolution of technology. This special report published in Stroke draws an analogy between the current global health crisis caused by the COVID-19 pandemic and the damage occasioned by the world wars, and exposes an optimistic point of view regarding the adjustments vascular neurologists have made to take care of stroke patients and how this may influence the way we deliver stroke care in the future.

Endovascular Thrombectomy With or Without Intravenous Alteplase: ESO-WSO Large Clinical Trials Webinar

Parneet Grewal, MD
@parneetgrewal6

ESO-WSO 2020 Large Clinical Trials Webinar
Presenter: Dr. Jianmin Liu (China)
Article: Yang P, Zhang Y, Zhang L, Zhang Y, Treurniet KM, Chen W, et al, for the DIRECT-MT Investigators. Endovascular Thrombectomy with or without Intravenous Alteplase in Acute Stroke. NEJM. 2020.

The goal of current therapeutic strategies for acute ischemic stroke with large vessel occlusion (LVO) is recanalization of the occlusion before irreversible damage has occurred. In this large multicenter, prospective, randomized, open-label trial with blinded outcome assessment, Dr. Jianmin Liu and his team aimed to answer the question of whether mechanical thrombectomy (MT) alone (thrombectomy alone group) would be non-inferior to combined treatment of IV-tPA and MT (combined group) in patients with LVO.  

This trial included patients ³ 18 years of age who presented to 41 pre-selected academic medical centers in China within 4.5 hours of symptom onset, had National Institutes of Health Stroke Scale (NIHSS) ³ 2 with imaging showing an LVO (intracranial segment of ICA, M1 or proximal M2 only). Any patients who did not meet American Heart Association/American Stroke Association guidelines for alteplase or MT were not included in the trial. The standard dose of tPA at 0.9 mg/kg was used, and the first-line strategy for MT was stent-retriever. Statistically, the trial was designed to provide 80% power (at a two-sided alpha level of 0.05) to determine a non-inferiority margin of 0.8. 656 patients were randomized in 1:1 fashion by a web-based system with 327 patients in the thrombectomy alone group and 329 patients in the combined group. The patient enrollment period was 17 months (February 23, 2018, to July 2, 2019). The baseline characteristics of patients were similar in both the groups with a median age of 69 years, median NIHSS score of 17, and median ASPECTS value of 9. The median duration from stroke onset to randomization was 167 minutes in the thrombectomy alone group and 177 minutes in combined group with time from randomization to groin puncture being 31 minutes and 36 minutes, respectively.

Diabetes Mellitus, But Not Prediabetes, Associated With Poorer Cognitive Performance After Stroke

Lina Palaiodimou, MD

Lo JW, Crawford JD, Samaras K, Desmond DW, Köhler S, Staals J, et al. Association of Prediabetes and Type 2 Diabetes With Cognitive Function After Stroke: A STROKOG Collaboration Study. Stroke. 2020.

Diabetes mellitus (DM) affects about 422 million people and is one of the leading causes of death worldwide (World Health Organization). More importantly, the burden of type 2 diabetes (T2D) has been rising relentlessly in all countries in the past three decades. However, it is estimated that a significant percentage of cases of T2D remain undiagnosed. DM is one of the major modifiable risk factors for stroke. In addition, it has been associated with adverse outcomes after stroke, including higher mortality, poorer neurological and functional outcomes, longer hospital stay, higher readmission rates, and stroke recurrence. Another outcome, the post-stroke cognitive function, and its relationship with DM, are being evaluated in the STROKOG collaboration study.

Lo et al. for the STROKOG collaboration present a meta-analysis of individual participant data (IPD) derived from seven international post-stroke cohorts with the aim to investigate the relationship between T2M and prediabetes with cognitive impairment after stroke.

ESO-WSO Large Clinical Trials Webinar: BASICS

Rachel Forman, MD
@bustinclots247

I was happy to see that although the ESO-WSO 2020 annual meeting was postponed, we still had the opportunity to virtually hear the results of some recent large clinical trials. One of the five trials presented was the Basilar Artery International Collaboration Study (BASICS) presented by Dr. Wouter Schonewille from The Netherlands. Posterior circulation occlusions have been largely excluded from the main endovascular randomized control trials, so these results were highly anticipated. 

Many of us are familiar with the devastating effects of a basilar artery occlusion (BAO), and from a personal experience, some of these cases have been very challenging without having the guidance of large trials as we do with anterior circulation occlusions. The clinical presentations, stroke severity, and collateral patterns are inherently different. This trial was an international, multicenter, controlled trial with randomized treatment-group assignments investigating the efficacy and safety of endovascular therapy (EVT) plus best medical management (BMM) versus BMM alone <6 hours of estimated time of BAO. Patients were randomly assigned (1:1 ratio) to EVT+BMM or BMM alone and stratified according to: randomizing center, use of IVT, and NIHSS (<20 vs >20). The enrollment period was from 2011 through 2019. Patients were excluded with intracranial hemorrhage, extensive brainstem ischemia, or cerebellar mass effect/acute hydrocephalus. The calculated sample size was 300 patients assuming favorable outcome in 46% with EVT+BMM and 30% with BMM. Primary outcome was mRS <3 at 90 days. Secondary outcome measures included clinical outcomes (mRS 0-2 at 90 days and mRS distribution) and imaging outcomes (posterior circulation ASPECTS score at 24 hours and basilar artery patency at 24 hours). 

COVID-19 Pandemic Pre-Hospital Acute Stroke Triage: Things to Consider

Elizabeth M. Aradine, DO

Goyal M, Ospel JM, Southerland AM, Wira C, Amin-Hanjani S, Fraser JF, et al. Prehospital Triage of Acute Stroke Patients During the COVID-19 Pandemic. Stroke. 2020.

The COVID-19 pandemic has changed the process of pre-hospital acute stroke triage. Actions such as EMS providers assessing a patient, walking into a patient’s room, transferring a patient to a comprehensive stroke center: These are things we once did without considering if we will contract or spread a virulent airborne virus. Now, special precautions are needed to provide acute stroke care, and they pose various challenges to the process of pre-hospital acute stroke triage. The authors of “Pre-hospital Triage of Acute Stroke Patients During the COVID-19 Pandemic” have established a guide to address these issues, and below is each challenge and possible solution. 

EMS providers need to obtain additional history regarding COVID-19 symptoms or exposures which may not be readily available. The authors propose that EMS providers use the COVID-19 Screening Tool, 5 questions on signs, symptoms, COVID-19 contacts, and patient age plus non-respiratory symptoms, as a quick way to assess for COVID-19. EMS providers can then communicate a positive screen to the receiving hospital so they can efficiently prepare for a protected stroke code.  Proper donning of PPE can be time consuming, thus the authors propose donning PPE prior to the patient’s arrival to minimize delay in the acute stroke evaluation. Symptomatic COVID-19 patients may need supplemental oxygen or intubation before arrival to the hospital. The authors propose continuous monitoring of vitals and to provide necessary emergent respiratory treatments by EMS after donning appropriate PPE. Staff shortages can occur due to quarantine or illness, leaving these duties to be covered by other providers who may be unfamiliar with acute stroke care. Simulation training can provide training for these new roles. COVID-19 positive stroke patients may need treatment at comprehensive stroke centers, but initially may not be transported directly to one due to location or other factors. Additionally, inter-facility transfers may be delayed due to unavailable transport staff for a COVID-19 positive stroke patient. The authors propose coordination between EMS and hospitals to facilitate re-routing patients to the appropriate hospital, for example, routing suspected LVO patients directly to a comprehensive stroke center. Not only could this prevent delay in acute stroke treatment, but it could also minimize PPE use and unnecessary staff exposure to COVID-19.

Vitamin K Antagonists: Insufficient Aid for Embolism and Risky for Intracranial Hemorrhage

Elena Zapata-Arriaza, MD
@ElenaZaps

Meinel TR, Kniepert JU, Seiffge DJ, Gralla J, Jung S, Auer E, et al. Endovascular Stroke Treatment and Risk of Intracranial Hemorrhage in Anticoagulated Patients. Stroke. 2020;51:892–898.

Symptomatic intracranial hemorrhage (sICH) involves a potential complication in patients treated with rtpa or mechanical thrombectomy (MT), which influences functional and vital prognosis of ischemic stroke patients. Patients under oral anticoagulation (OAC) suffer higher risk of sICH per se; however, the association of mentioned oral treatment with recanalization therapies (IV fibrinolysis or MT) may increase cerebral bleeding. This is the aim of Dr. Meinel and colleagues, among others, like mortality and sICH risk in MT patients under OAC, sensitivity analysis with patients with confirmed therapeutic anticoagulation activity, and finally the presentation of a meta-analysis about the topic.

The authors performed a retrospective, multicenter non-randomized observational study to investigate safety and efficacy of a market-release neurothrombectomy device, including their data in the BEYOND-SWIFT registry. Patients were grouped according to their OAC intake prior to admission: Group 1: VKA (vitamin K antagonist); Group 2: DOACs (Direct oral anticoagulants); Group 3: No OAC. The primary endpoint was sICH rate (according to ECASS II (European Co-Operative Acute Stroke Study-II) criteria). The secondary endpoints were technical efficacy and all-cause mortality at 3 months.