American Heart Association

clinical

Focal CTP Abnormalities in TIA

Deepak Gulati, MD

Meyer IA, Cereda CW, Correia PN, Zerlauth JP, Puccinelli F, Rotzinger DC, et al. Factors Associated With Focal Computed Tomographic Perfusion Abnormalities in Supratentorial Transient Ischemic Attacks. Stroke. 2017

TIAs are associated with an increased risk of debilitating recurrent stroke along with increased risk for cardiovascular morbidity and mortality. Several studies have demonstrated poor agreement regarding TIA diagnosis among Emergency Department (ED) physicians, neurologists, and even stroke specialists. Although many biomarkers for TIA diagnosis are promising, none has been proven to be sufficiently reliable for diagnosis of TIA. Substantial international variation exists in clinical practice and policies for hospital admission for patients with TIA. International guidelines also differ in their recommendations for brain and vascular imaging after TIA, with imaging either immediately or several days after symptom onset, and brain imaging by either CT or MRI recommended. It has been reported that CTP shows focal perfusion deficits in up to a third of suspected patients with TIA and could also predict functional outcome at 3 months. It has been shown that limiting urgent assessment to patients with a score of 4 or more on ABCD2 would miss approximately 20% of those with early recurrent strokes. There appears to be a need for more research focus on dynamic imaging modalities like CTP or MRP, in addition to clinical information for better diagnosis and management of TIA.

By |February 16th, 2018|clinical|0 Comments

Statins and Intracerebral Hemorrhage — Causation or Coincidence?

Kevin S. Attenhofer, MD

Gaist D, Goldstein LB, Cea Soriano L, García Rodríguez LA. Statins and the Risk of Intracerebral Hemorrhage in Patients With Previous Ischemic Stroke or Transient Ischemic Attack. Stroke. 2017

Statins are some of the most commonly prescribed drugs in the fields of cardio- and cerebrovascular disease. In the last two decades, randomized controlled trials have shown that statin therapy reduces the risk of major vascular events in high-risk populations. Definitions of these populations have changed over the years, but currently the AHA/ASA stroke guidelines recommend statins in all patients for secondary stroke prevention.

Despite the ubiquitous usage of statins, it has been noted that some data (from the Heart Protection Study (HPS) and the Stroke Prevention with Aggressive Reductions of Cholesterol Levels (SPARCL)) suggests that the benefits of high-dose atorvastatin treatment was partially offset by an increase in hemorrhagic stroke. The association of statins and intracerebral hemorrhage (ICH) has remained controversial ever since. Subsequent meta-analyses and case control studies — some of which included data from SPARCL — found no associated increase in the risk of ICH in patients on statin therapy.

Author Interview: Dr. Greg Albers, on DEFUSE 3 and its Implications for Systems of Stroke Care in the U.S.

Dr. Greg Albers

Dr. Greg Albers

A conversation with Dr. Greg Albers, professor of neurology at Stanford and the principal investigator for DEFUSE 3.

Interviewed by Dr. Kaustubh Limaye, assistant professor of neurology in the division of cerebrovascular diseases at the University of Iowa, at the International Stroke Conference 2018 following the presentation of the final results of DEFUSE 3 and a simultaneous publication in the New England Journal of Medicine.

Albers GW, Marks MP, Kemp S, Christensen S, Tsai JP, Ortega-Gutierrez S, et al. Thrombectomy for Stroke at 6 to 16 Hours with Selection by Perfusion Imaging. New England Journal of Medicine. 2018

Dr. Limaye: Dr. Albers, first accept my hearty congratulations on the phenomenal success of the DEFUSE 3 trial.

Dr. Albers: Thank you so much.

Dr. Limaye: Just like everybody else, I was patiently waiting to hear what the results were going to be. All of us are delighted looking at the strong treatment effect that DEFUSE 3 showed in this extended time window. Thanks again for taking time out from your busy schedule. I’m sure this conference was extremely busy for you.

Dr. Albers: It’s been a very exciting week. We’ve been anticipating this for some time, and it’s wonderful to see this come to fruition.

Therapeutic Management of Aspirin Failure – Does Changing the Antiplatelet Regimen Help?

Philip Chang, MD

Lee M, Saver JL, Hong KS, Rao NM, Wu YL, Ovbiagele B. Antiplatelet Regimen for Patients with Breakthrough Strokes While on Aspirin. Stroke. 2017

When your patient has a stroke while on an antiplatelet regimen, a common practice is to switch it. If they were on aspirin, change to clopidogrel. If on clopidogrel, one may think of switching to aspirin plus dipyridamole. While there has been much theory about aspirin failure, or aspirin resistance, there has been scant evidence to suggest that switching antiplatelet agents may benefit patients. Clinicians have switched antiplatelet regimens under the common philosophy, “Insanity is doing the same thing over and over again and expecting different results.” This is with the underlying theory that patients who experience recurrent stroke while on aspirin must have developed aspirin resistance, and blocking another antiplatelet pathway (like ADP) will confer some protective benefit. However, this theory has never been proven or disproven by a clinical study. This article by Lee et al is a great step into this clinical conundrum.

Association Between Prehospital Blood Pressure and Extent of Bleeding in Patients with Acute Intracerebral Hemorrhage

Andrea Morotti, MD

Rodriguez-Luna D, Rodriguez-Villatoro N, Juega JM, Boned S, Muchada M, Sanjuan E, et al. Prehospital Systolic Blood Pressure Is Related to Intracerebral Hemorrhage Volume on Admission. Stroke. 2018

Elevated blood pressure has been consistently associated with active bleeding and unfavorable prognosis in acute intracerebral hemorrhage (ICH). Dr. Rodriguez-Luna and colleagues investigated whether systolic blood pressure (SBP) in the prehospital phase correlates with admission SBP and extent of bleeding measured as baseline ICH volume. To explore this association, a prospectively collected cohort of ICH patients was retrospectively analyzed. A total of 219 patients qualified for the analysis (mean age 76, 54% males), with mean baseline ICH volume of 25 mL. Prehospital SBP was strongly correlated with admission SBP (r=0.552; P<0.001) and baseline ICH volume (ρ=0.189; P=0.006), as shown in the Figure.

Scatterplots showing the relationship between prehospital systolic blood pressure (SBP) and time from symptom onset (A), SBP on admission (B), and intracerebral hemorrhage (ICH) volume on admission (C).

Figure: Scatterplots showing the relationship between prehospital systolic blood pressure (SBP) and time from symptom onset (A), SBP on admission (B), and intracerebral hemorrhage (ICH) volume on admission (C).

Hitting the Sack After Brain Attack: The Relationship Between Sleep, Preconditioning and Stroke

Danny R. Rose, Jr. MD

Pincherle A, Pace M, Sarasso S, Facchin L, Dreier JP, Bassetti CL. Sleep, Preconditioning and Stroke. Stroke. 2017

Sleep is a complex yet fundamental physiological state with wide-reaching implications for a variety of disease states that are still incompletely understood. The study of the various deleterious effects of sleep deprivation and benefits of physiologic sleep are ripe for application to the pathophysiology of stroke, which itself involves the study of the negative and positive effects of physiologic stressors and the importance of recovery and regeneration. Coauthors Pincherle and Pace et al. recently published a comprehensive review of current research in human and animal models about the effects of sleep as well as preconditioning in the context of acute ischemic stroke.

Sleep disorders are exceedingly prevalent; it is estimated that up to one third of adults do not get adequate sleep. Sleep deprivation (SD)/fragmentation induces autonomic nervous system dysfunction, increases inflammation and induces procoagulant factors and oxidative stress. In acute stroke, animal models show that sleep deprivation increases apoptosis and impairs neuroplasticity and neurogenesis. In human studies, sleep-disordered breathing (SDB) has been significantly associated with hypertension, atherosclerosis and cardiac arrhythmia. In addition, SDB was identified as an independent stroke predictor in one meta-analysis (OR 2.24, CI 1.57-3.19), and was shown to have a dose-response relationship in stroke/TIA survivors with respect to recurrent stroke/TIA and all-cause mortality in a separate review. Intermittent hypoxia, intrathoracic pressure changes, sympathetic activation, blood pressure lability, endothelial dysfunction and proinflammatory factors are all likely contributing factors associated with SDB.

By |January 17th, 2018|clinical|0 Comments

Eating Healthy: Tips for Stroke Prevention

Rohan Arora, MD

Larsson SC. Dietary Approaches for Stroke Prevention. Stroke. 2017

This review by Susanna Larsson focuses on the current evidence from randomized controlled trials and prospective studies on dietary modifications that could help with stroke prevention.

The article is very important since diet is one of the modifiable factors that can help with reducing the risk of stroke and promote cardiovascular health. The stroke survivors or their family members are of utmost curiosity to change their diet after seeing a family member suffer from stroke.

Bridging Therapy for Endovascular Thrombectomy: A Role for Direct Mechanical Thrombectomy?

Mark R. Etherton, MD PhD

Bellwald S, Weber R, Dobrocky T, Nordmeyer H, Jung S, Hadisurya J, et al. Direct Mechanical Intervention Versus Bridging Therapy in Stroke patients Eligible for Intravenous Thrombolysis. Stroke. 2017

In this entry, I discuss the matched pairs analysis of IV tPA eligible patients with large-vessel occlusion (LVO) of the anterior circulation that underwent endovascular thrombectomy (EVT) with or without pre-treatment with IV tPA.

The clinical importance of understanding the role of bridging therapy in patients with LVO is critical for efficaciously triaging this population to stroke centers. The hypothetical scenario is, how should emergency medical services appropriately triage a patient with suspicion for LVO with regards to transfer to a primary stroke center with tPA capabilities or a comprehensive stroke center with EVT capabilities that is further away? This scenario epitomizes why there is great interest in understanding the contribution that bridging therapy with tPA has on outcomes in patients with LVO of the anterior circulation.

Stressing Over Sugar: Prognostic Implications of Stress Hyperglycemia After Stroke

Kevin S. Attenhofer, MD

Pan Y, Cai X, Jing J, Meng X, Li H, Wang Y, et al. Stress Hyperglycemia and Prognosis of Minor Ischemic Stroke and Transient Ischemic Attack: The CHANCE Study (Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events). Stroke. 2017

Diabetes is becoming increasingly prevalent worldwide, with over 30 million people diagnosed in the United States as of 2015. It is no secret that diabetes is an independent risk factor for stroke. In fact, mortality is higher and post-stroke outcomes are poorer in patients with stroke and uncontrolled glucose levels.

In some patients, a phenomenon of stress hyperglycemia is observed at the time of stroke. This is a relative increase in glucose during an acute critical illness. It is an ill-defined metric with no consistent definition in the literature. Previous studies have shown that stress hyperglycemia is a better predictive biomarker of critical illness than absolute hyperglycemia. The authors of this paper sought to determine an association between stress hyperglycemia and incidence of new stroke or TIA following index ischemic stroke.

So You’ve Found Some Microbleeds, What Now?

Stephen Makin, PhD
@StephenMakin

Shoamanesh A, Charidimou A, Sharma M, Hart RG. Should Patients With Ischemic Stroke or Transient Ischemic Attack With Atrial Fibrillation and Microbleeds Be Anticoagulated? Stroke. 2017

Anyone who has been to a stroke unit’s imaging meeting will know this situation.

Someone has performed an MRI on their patient with atrial fibrillation, someone who is at high risk of a further stroke, and would usually be started on anticoagulation. Now it shows some microbleeds, and they are considering whether they should still offer anticoagulation.

Someone else will tell you that a meta-analysis of observational studies suggests that CMB is associated with an increased risk of both haemorrahgic and ischaemic stroke.

Someone mutters that maybe the MRI has just caused more trouble, and wonders why you requested it in the first place; after all, we have always managed to diagnose stroke without MRI for decades.

Someone else will say that as none of the trials of anticoagulation required MRI at study entry, so patients with microbleeds must have been included in these studies.

By |January 8th, 2018|clinical|0 Comments