American Heart Association

Racial and Ethnic Disparities in Thrombectomy for Acute Stroke

Rachel Forman, MD

Rinaldo L, Rabinstein AA, Cloft H, Knudsen JM, Rangel Castilla L, Brinjikji W. Racial and Ethnic Disparities in the Utilization of Thrombectomy for Acute Stroke: Analysis of Data From 2016 to 2018. Stroke. 2019

I was excited for the chance to review this article, as this topic is near and dear to my heart as someone who does community stroke education to help improve healthcare disparities in this area. From my experience in providing stroke education to more diverse communities, there is much less knowledge in terms of recognizing stroke symptoms and the importance of prompt care to be eligible for tPA and mechanical thrombectomy (MT).  Unfortunately, I was not surprised when I read the results of this paper. 

It has already been established that minority patients receive less MT; however, this study looked at updated data (2016-2018) to see if this still held true following the publication of multiple positive MT trials in 2015. MT has become increasingly utilized after a series of positive trials published in 2015 and is now the standard of care for treatment of stroke due to large vessel occlusion. For more information on these trials, the HERMES collaboration is a meta-analysis of five major trials in The Lancet, published in 2016. 

By |August 21st, 2019|clinical|0 Comments

Better is the Enemy of Good

Elena Zapata-Arriaza, MD

García-Tornel A, Requena M, Rubiera M, Muchada M, Pagola J, Rodriguez-Luna D, et al. When to Stop: Detrimental Effect of Device Passes in Acute Ischemic Stroke Secondary to Large Vessel Occlusion. Stroke. 2019;50:1781–1788

The achievement of mTICI 3 after one pass, known as first pass effect, is clearly associated with better functional outcome, as compared with those patients with more passes needed to obtain full recanalization. But how many passes should we attempt before stop procedure? Or maybe we should pursue a good (TICI 2B) but not perfect recanalization, instead of seeking TICI 3, because such recanalization is more than enough for patient outcome?

These are some of the aims of this study, in addition to finding the relation between number of passes and recanalization degree and clinical outcome.

Can We Predict Post Thrombectomy Hematoma?

Elizabeth M. Aradine, DO

Boisseau W, Fahed R, Lapergue B, Desilles J-P, Zuber K, Khoury N, et al. Predictors of Parenchymal Hematoma After Mechanical Thrombectomy: A Multicenter Study. Stroke. 2019

Parenchymal hematoma (PH) is a potential complication of IV thrombolytics or mechanical thrombectomy; however, risk factors for hematoma after thrombectomy are still uncertain. PH after acute stroke intervention can increase morbidity and mortality. In this study, the authors retrospectively reviewed data from a registry of thrombectomy patients to identify variables to predict post thrombectomy PH. Patients presenting with an anterior circulation large vessel or intracranial carotid occlusion who had a thrombectomy from 2011-2016 were included. MRI or CT based brain and vessel imaging were used to select patients for thrombectomy and to calculate the ASPECT score. Post thrombectomy, a 24-hour brain image was routinely performed on all patients to evaluate for PH. PH was classified using the European Cooperative Acute Stroke Study (ECASS) criteria. 90-day post stroke outcome was assessed using the mRS. This data was compared to baseline patient characteristics including age, smoking status, hypertension, diabetes, admission NIHSS, and antiplatelet or anticoagulation use. Data on the presence of collateralization on angiogram and general anesthesia use was also recorded.

By |August 19th, 2019|clinical|0 Comments

Article Commentary: “Causes and Risk Factors of Cerebral Ischemic Events in Patients With Atrial Fibrillation Treated With Non–Vitamin K Antagonist Oral Anticoagulants for Stroke Prevention”

Yan Hou, MD, PhD

Paciaroni M, Agnelli G, Caso V, Silvestrelli G, Seiffge DJ, Engelter S, et al. Causes and Risk Factors of Cerebral Ischemic Events in Patients With Atrial Fibrillation Treated With Non–Vitamin K Antagonist Oral Anticoagulants for Stroke Prevention: The RENo Study. Stroke. 2019;50:2168–2174

Non–vitamin K antagonist oral anticoagulants (NOACs) are currently recommended as the stroke prevention for patients with nonvalvular atrial fibrillation (AF). Despite compliance with NOAC, patients with nonvalvular AF may still experience ischemic cerebrovascular events. The RENO study is a multicenter case-control study to identify the etiology and risk factors for ischemic events occurring during NOACs (dabigatran, apixaban, rivaroxaban, or edoxaban) therapy in patients with nonvalvular AF.

The study included 713 cases (641 ischemic strokes and 72 TIA) and 700 controls (patients did not experience cerebrovascular events). Cases who did not guarantee compliance or who had suspended NOAC at least 24 hours before the cerebrovascular event were excluded. Most strokes (64%) occurring during NOACs therapy were caused by cardioembolism, but about 30% of strokes were found due to non-cardioembolic etiology. Among the risk factors (age, sex, hypertension, diabetes mellitus, current cigarette smoking, hyperlipidemia, ischemic heart disease, peripheral artery disease, alcohol abuse, obesity, previous stroke/transient ischemic attack, creatinine clearance, duration of NOAC treatment, doses of NOACs, AF classification, CHA2DS2-VASc score, left atrial enlargement on echo), off-label low doses of NOACs (OR, 3.18), atrial enlargement (OR, 6.64), hyperlipidemia (OR, 2.40), and high CHA2DS2-VASc score (OR, 1.72 for each point increase) were associated with ischemic events. The reasons for prescribing low doses of NOAC included fear of bleeding, history of bleeding, concomitant antiplatelet therapy, recurrent falls, amyloid angiopathy, anemia, history of cancer, age, gastrointestinal discomfort, and hypertension or other causes. Low clearance of creatinine (OR, 0.98 for 1 mL/min increase) and high CHA2DS2-VASc score (OR, 1.35 for each point increase) were also found associated with prescription of low-dose NOACs.   

When More is More: The Benefit of Combination Therapy for Large Vessel Occlusion Ischemic Stroke

Charlotte Zerna, MD, MSc

Young-Saver DF, Gornbein J, Starkman S, Savel JL. Magnitude of Benefit of Combined Endovascular Thrombectomy and Intravenous Fibrinolysis in Large Vessel Occlusion Ischemic Stroke. Stroke. 2019

Little is known about the effect size of the combination of intravenous alteplase therapy (IVT) and endovascular therapy (EVT) compared to supportive treatment alone for patients with anterior circulation large vessel occlusion (LVO). At the time EVT was proven effective with the randomized controlled trials, IVT had already been the standard of care for almost 20 years and thus chosen as a comparator group. Since no randomized controlled trial data are available to compare IVT+EVT to supportive therapy alone, Young-Saver et al. chose to undertake a post-hoc analysis matching patients from the Solitaire With the Intention for Thrombectomy as Primary Endovascular Treatment (SWIFT-PRIME) trial with patients from the 2 National Institute for Neurological Disorders and Stroke Recombinant Tissue Plasminogen Activator (NINDS rt-PA) trials.

In the main analysis, a total of 240 patients (80 from the SWIFT-PRIME IVT+EVT group, 80 from the NINDS rt-PA Study IVT alone group, and 80 from the NINDS rt-PA Study placebo group) were 1:1 inverse variance matched for presenting National Institutes of Health Stroke Scale (NIHSS) score to identify NINDS rt-PA Study patients likely harboring LVOs and age since it is a strong determinant of outcome. The 90-day modified Rankin Scale (mRS) score was used as the outcome, analyzed both as an ordinal scale (shift across all 7 mRS levels) with ordinal logistic regression analysis and as a dichotomized outcome ( 0-1 vs. 2-6 and 0-2 vs. 3-6) using Fisher exact test.

By |August 14th, 2019|clinical|0 Comments

More Thrombectomies Might Mean Less Hemicraniectomies

Raffaele Ornello, MD

Rumalla K, Ottenhausen M, Kan P, Burkhardt J-K. Recent Nationwide Impact of Mechanical Thrombectomy on Decompressive Hemicraniectomy for Acute Ischemic Stroke. Stroke. 2019;50:2133–2139

Decompressive hemicraniectomy (DHC) is performed to treat malignant cerebral edema (MCE), a potentially devastating consequence of ischemic stroke. It has been hypothesized that mechanical thrombectomy (MT) procedure might prevent the need of MCE in patients with the most severe forms of ischemic stroke by restoring the blood flow in the ischemic penumbra.

To verify that hypothesis, the authors of the present study reviewed the National Inpatient Sample, a large United States dataset of hospitalized patients, to assess the trends of DHC and MT from 2012 to 2016, the years in which there was a massive implementation of MT. The study showed that the increase of MT procedure was paralleled by a sharp decrease in the number of DHCs, that was more evident after 2015, when the MT guidelines were published. Data also showed that patients undergoing MT were less likely to undergo DHC.

By |August 13th, 2019|clinical|0 Comments

Blood Pressure Lowering During Endovascular Thrombectomy Associated With Poor Radiological and Clinical Outcome

Piyush Ojha, MBBS, MD, DM

Petersen NH, Ortega-Gutierrez S, Wang A, Lopez GV, Strander S, Kodali S, et al. Decreases in Blood Pressure During Thrombectomy Are Associated With Larger Infarct Volumes and Worse Functional Outcome. Stroke. 2019;50:1797–1804

Recent studies have shown that acute ischemic stroke patients with large vessel occlusion (LVO) have good clinical outcome following endovascular thrombectomy (EVT), which is now a new standard of care. However, only 46% of patients undergoing EVT were functionally independent (mRS 0-2) at 90 days, and only 10% were neurologically normal in the meta-analysis of EVT trials [Highly Effective Reperfusion evaluated in Multiple Endovascular Stroke Trials (HERMES)].1 Several factors could potentially contribute to this observation. Both clinical and imaging variables have been shown to correlate with poor outcome, especially age, stroke severity, lack of effective reperfusion and infarct volume.  

Management of blood pressure is hotly debated in the stroke literature. There are theoretical concerns and benefits of acute blood pressure lowering in acute ischemic stroke. Blood pressure fluctuations during EVT could lead to inadequate cerebral perfusion causing poor final radiological (infarct progression) and clinical outcomes (functional status) in patients with LVO. Hypotension prior to reperfusion may compromise collateral flow, which may be further worsened by the exhaustion of compensatory vasodilatory capacity distal to the occluded vessel and the loss of intrinsic autoregulatory function in the ischemic tissue leading to a poor clinical and radiological outcome. 

By |August 7th, 2019|clinical|0 Comments

To Bridge or Not to Bridge

Jennifer Harris, MD

Altavilla R, Caso V, Bandini F, Agnelli G, Tsivgoulis G, Yaghi S, et al. Anticoagulation After Stroke in Patients With Atrial Fibrillation: To Bridge or Not With Low-Molecular-Weight Heparin? Stroke. 2019; 50:2093–2100

Despite evidence that it might be harmful, some clinicians still use bridging therapy with low-molecular-weight heparin (LWMH) to prevent early recurrent stroke in patient with acute stroke and history of atrial fibrillation. In the August issue of Stroke, Altavilla et al. report the results of pooled observational data from RAF (Early Recurrence and Cerebral Bleeding in Patients With Acute Ischemic Stroke and Atrial Fibrillation) and RAF NOAC (Early Recurrence and Major Bleeding in Patients With Acute Ischemic Stroke and Atrial Fibrillation Treated With Non–Vitamin K Oral Anticoagulants) to shed some light on the clinical characteristics and differences in outcomes of patients who received or did not receive bridging therapy.

The primary outcome was a composite of ischemic stroke, TIA, systemic embolism, symptomatic cerebral bleeding, and major extracerebral bleeding observed at 90 days after acute ischemic stroke.

By |August 6th, 2019|clinical|0 Comments

Reconsidering Role of Immune System in Neuropathophysiology After Stroke

Lin Kooi Ong, PhD

Perego C, Fumagalli S, Miteva K, Kallikourdis M, De Simoni M-G. Combined Genetic Deletion of IL (Interleukin)-4, IL-5, IL-9, and IL-13 Does Not Affect Ischemic Brain Injury in Mice. Stroke. 2019;50:2207–2215

Primary brain injury occurs immediately after the onset of stroke, and triggers a cascade of immune responses including glial activation, recruitment of peripheral immune cells and release of cytokines and chemokines. These inflammation responses may aggravate brain injury by enhancing oxidative stress, production of neurotoxic proteins and disruption of neurovascular unit. On the other hand, inflammation may also participate in waste clearance, production of neurotropic factors and support the survivor of neurons. The recognition of the crucial role of inflammation after stroke has motivated stroke researchers to investigate novel interventions to target brain inflammation processes, leading to improve neurological outcome.

Article Commentary: “Timing and Relevance of Clinical Improvement After Mechanical Thrombectomy in Patients With Acute Ischemic Stroke”

Muhammad Taimoor Khan, MD

Rudilosso S, Urra X, Amaro S, Llull L, Renú A, Laredo C, et al. Timing and Relevance of Clinical Improvement After Mechanical Thrombectomy in Patients With Acute Ischemic Stroke. Stroke. 2019;50:1467–1472

Mechanical thrombectomy can prevent functional dependence in about half of the patients with acute ischemic stroke from proximal vessel occlusion. Dr. Rudilosso and his colleagues studied the relevance of the timing of clinical improvement in the prediction of long-term outcome in patients treated with mechanical thrombectomy. Patients who presented substantial clinical improvement SCI at the earliest assessment after MT had the highest odds for functional recovery at 3 months and an improvement >30% in National Institutes of Health Stroke Scale score NIHSS at the end of MT represents a reliable prognostic marker.

By |August 2nd, 2019|clinical|0 Comments