American Heart Association

Yearly Archives: 2017

History of Aneurysmal Subarachnoid Hemorrhage

Tapan Mehta, MBBS, MPH

Korja M, Kivisaari R, Rezai Jahromi B, Lehto H. Natural History of Ruptured but Untreated Intracranial Aneurysms. Stroke. 2017

Over the past fifty years, understanding of the natural course of aneurysmal subarachnoid hemorrhage (aSAH) has concurrently transformed the standard management approaches. With the awareness of risk related to aneurysm re-rupture (about 15% within few hours and overall cumulative risk of 40%–50% at 6 months) among patients who survive the initial event, securing the aneurysm as soon as possible has become the standard of care. Korja et al present an interesting retrospective observational study that depicts the natural course of untreated ruptured intracranial aneurysms.

By |November 10th, 2017|clinical|Comments Off on History of Aneurysmal Subarachnoid Hemorrhage
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Using CT Perfusion to Predict Hemorrhagic Transformation

Brian Marcus, MD

Li Q, Gao X, Yao Z, Feng X, He H, Xue J, et al. Permeability Surface of Deep Middle Cerebral Artery Territory on Computed Tomographic Perfusion Predicts Hemorrhagic Transformation After Stroke. Stroke. 2017

The authors of this study utilized CT perfusion (CTP) to assess blood brain barrier integrity and to help predict which patients are at risk of hemorrhagic transformation after receiving tPA and/or mechanical thrombectomy. They note that patients who have proximal MCA-M1/distal ICA occlusions are at an increased susceptibility of hemorrhagic transformation, particularly in the deep MCA territory supplied by the lenticulostriate arteries. They aimed to explore the relationship and potential risk factors between permeability and hemorrhagic transformation in the deep MCA territory by utilizing CT perfusion imaging.

The authors performed a multisite retrospective study, specifically looking at patients that were found to have a deep MCA territory hemorrhagic transformation at 24 hours (and had received CT perfusion and CT angiography on admission). In their study, they noted that patients with a proximal MCA/distal ICA and poor collateral circulation had increased permeability in the deep MCA territory.

By |November 8th, 2017|clinical, diagnosis and imaging|Comments Off on Using CT Perfusion to Predict Hemorrhagic Transformation
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Reducing Recurrent Strokes with Secondary Risk-Factor Modification — Reflections from Temporal Trends in a Population-Based Study

Gurmeen Kaur, MBBS
@kaurgurmeen

Bergström L, Irewall AL, Söderström L, Ögren J, Laurell K, Mooe T. One-Year Incidence, Time Trends, and Predictors of Recurrent Ischemic Stroke in Sweden From 1998 to 2010: An Observational Study. Stroke. 2017

The risk of recurrent stroke has been on a decline as per estimates from different countries, including Italy, Taiwan and the “Western world.” Rikstroke is the Swedish Stroke Register where all Swedish hospital admissions because of stroke are recorded. The authors describe an excellent longitudinal study design where patients with ischemic strokes were followed up from 1998 to 2009. From the year 1998, all Swedish hospitals and rehab centers report their admissions to the Rikstroke registry, which had an astounding 85% coverage in the year 2009.

The recurrence of ischemic stroke events was calculated by amalgamating the Rikstroke registry with the Swedish National Inpatient Register (IPR), which contains data about diagnoses and dates of discharge from hospitalizations in Sweden.

By |November 6th, 2017|clinical, epidemiology and genetics|Comments Off on Reducing Recurrent Strokes with Secondary Risk-Factor Modification — Reflections from Temporal Trends in a Population-Based Study
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Hide and Seek: Using Cardiac MRI to Find a Hidden Clot in ESUS

Kevin S. Attenhofer, MD

Takasugi J, Yamagami H, Noguchi T, Morita Y, Tanaka T, Okuno Y, et al. Detection of Left Ventricular Thrombus by Cardiac Magnetic Resonance in Embolic Stroke of Undetermined Source. Stroke. 2017.

As has been reviewed in this blog many times before, embolic stroke of undetermined source (ESUS) is a novel clinical construct that is a hot topic for emerging diagnostic and therapeutic strategies. While many studies are evaluating methods to increase the detection rate of covert atrial fibrillation in this population, the authors of this paper demonstrate improved detection of left ventricular (LV) thrombi in ESUS patients using cardiac MRI versus TTE.

Currently, echocardiography is the test of choice when evaluating for intra-cardiac thrombus. Transesophageal echocardiography (TEE) is the gold standard technique for detecting left atrial or left atrial appendage thrombi. Transthoracic echocardiography (TTE) is used to evaluate the presence of LV thrombus, patent foramen ovale, depressed ejection fraction, etc. Recently, contrast enhanced cardiac magnetic resonance imaging (CE-CMR) has shown significantly better sensitivity than TTE for the diagnosis of LV thrombus (cardiac studies suggesting sensitivity of TTE was 40%, compared with 88% for CE-CMR) in patients with a history of myocardial infarction (MI) or LV dysfunction (LVEF < 30%).

By |November 3rd, 2017|clinical, diagnosis and imaging|Comments Off on Hide and Seek: Using Cardiac MRI to Find a Hidden Clot in ESUS
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Author Interview: Ramin Zand, MD, and Vida Abedi, PhD

A conversation with Ramin Zand, MD, Neurology Director of Clinical Stroke Operations, Northeastern Regional Stroke Director, Geisinger Health System, and Associate Professor of Neurology, University of Tennessee Health Science Center, and Vida Abedi, PhD, Research Scientist, Geisinger Health System, and Adjunct Professor, Virginia Tech, about using an artificial neural network to screen for stroke.

Interviewed by José G. Merino, MD, Associate Professor of Neurology, University of Maryland School of Medicine.

They will be discussing the paper “Novel Screening Tool for Stroke Using Artificial Neural Network,” published in the June issue of Stroke.

Dr. Merino: Could you please briefly summarize the key findings and put them in context of what was known before you did the study (i.e. an “elevator pitch” about your research)?

Vida Abedi, PhD

Vida Abedi, PhD

Drs. Zand and Abedi: We have developed ​a new computational method based on artificial intelligence to screen for the stroke in an emergency setting. Previous studies have shown that up to 25% of strokes can be initially misdiagnosed in the emergency department. The failure to recognize stroke in the emergency department is a missed opportunity for intervention. The goal of our study was to test if a supervised learning method could recognize and differentiate stroke from stroke mimics based on the patient demographics, risk factors, and certain clinical elements. Our results showed that in 6 out of the 10 data sets, the precision of our tool for the diagnosis of stroke was >90%. We believe that these methods can serve as a clinical decision support system and assist the emergency providers with early recognition of stroke.

Ramin Zand, MD

Ramin Zand, MD

By |November 1st, 2017|author interview, clinical, diagnosis and imaging|Comments Off on Author Interview: Ramin Zand, MD, and Vida Abedi, PhD
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Low-Dose Rivaroxaban Plus Aspirin: A New Way to Prevent Strokes?

Philip Chang, MD

Eikelboom JW, Connolly SJ, Bosch J, Dagenais GR, Hart RG, Shestakovska O, et al. Rivaroxaban with or without Aspirin in Stable Cardiovascular Disease. N Engl J Med. 2017

This landmark trial published in the New England Journal of Medicine found that in 27,395 patients with stable atherosclerotic cardiovascular disease (ASCVD), aspirin 100 daily plus rivaroxaban 2.5mg twice daily was superior to aspirin alone and rivaroxaban alone in preventing the primary outcome of cardiovascular death, stroke, or heart attack. In addition, secondary outcomes of all-cause death were also significantly lower in the aspirin-plus-rivaroxaban group. The effect size was large enough for the study to stop prematurely for superiority of the aspirin-plus-rivaroxaban group. From this, it is clear that treatment with rivaroxaban plus aspirin is superior to aspirin alone in a patient with coronary or peripheral vascular disease in preventing ischemic stroke (p=<0.001) without significantly increased adverse effects. However, this brings into the question – what about patients who already have a history of ischemic stroke? Ischemic stroke is an ASCVD risk equivalent, and this study brings into question – do we need to start adding apixaban for secondary ischemic stroke prevention for all-comers?

By |October 30th, 2017|clinical|Comments Off on Low-Dose Rivaroxaban Plus Aspirin: A New Way to Prevent Strokes?
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World Stroke Day: Sunday, October 29

Nerses Sanossian, MD, and José G. Merino, MD
Blogging Stroke Editors

World Stroke Day is an opportunity to focus on how to reduce the global burden of the deadliest and most morbid brain disease. Stroke is a global disease that exerts a particularly high burden on developing nations, where it is the second leading cause of death. Stroke remains a leading cause of death and disability throughout the United States and Europe despite many recent advances in stroke care. However, World Stroke Day also allows us an opportunity to recognize breakthroughs in stroke care and review priorities for the future.

Advances in acute stroke have created major disparities in care nationwide and worldwide. The four most impactful stroke treatments of the past 30 years — stroke units, intravenous thrombolysis, emergency/prehospital systems, and endovascular therapy — are currently available to the minority of people around the word. Most countries are just starting to develop stroke units. Intravenous thrombolysis is unavailable or beyond the financial means for most people in the world. Emergency systems of care are non-existent in most countries. Many countries do not have a single neuroendovascular practitioner. In a world where basic medical care is limited, how can advances in stroke care be translated into meaningful results?

By |October 27th, 2017|World Stroke Day|Comments Off on World Stroke Day: Sunday, October 29
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Serum Gamma-Glutamyl Transferase at Time of Stroke is Associated With Post-Stroke Mortality and Recurrent, Fatal Stroke

Neal S. Parikh, MD 
@NealSParikhMD

Tu W, Liu Q, Cao J, Zhao S, Zeng X, Deng A. γ-Glutamyl Transferase as a Risk Factor for All-Cause or Cardiovascular Disease Mortality Among 5912 Ischemic Stroke. Stroke. 2017

In light of an increasing interest in and understanding of the association between liver disease and cerebrovascular disease, Wen-Jun Tu and colleagues sought to explore the association between serum γ-glutamyl transferase (GGT) and post-stroke mortality.

In their well-designed and well-powered prospective, multicenter cohort observational study, the authors enrolled 5,912 patients within 24 hours of acute ischemic stroke. The study was conducted in China. They excluded patients with known hepatobiliary disease and alcohol abuse. Serum GGT level at baseline was the exposure of interest, and patients were followed for a median of 1 year with regular telephone interviews and review of death certificates. The primary outcome was all-cause mortality, and cardiovascular death (including fatal stroke) was separately adjudicated. Men and women were analyzed differently because normative values for GGT are sex-specific.

By |October 25th, 2017|clinical, prognosis|Comments Off on Serum Gamma-Glutamyl Transferase at Time of Stroke is Associated With Post-Stroke Mortality and Recurrent, Fatal Stroke
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Omega-3 Fatty Acid Biomarkers: A Potential Marker of Incident Ischemic Stroke Risk?

Mark R. Etherton, MD, PhD

Saber H, Yakoob MY, Shi P, Longstreth Jr. WT, Lemaitre RN, Siscovick D, et al. Omega-3 Fatty Acids and Incident Ischemic Stroke and Its Atherothrombotic and Cardioembolic Subtypes in 3 US Cohorts. Stroke. 2017

In this entry, I discuss a recent publication by Hamidreza Saber and colleagues regarding the relationship of circulating omega-3 fatty acids levels and incident ischemic stroke.

The authors set out to clarify the impact of omega-3 fatty acids on ischemic stroke incidence. Observational studies of self-reported omega-3 fatty acid consumption and omega-3 fatty acid supplementation trials have previously produced disparate results. As such, the authors quantified circulating omega-3 fatty acid levels in association with ischemic stroke incidence from 3 separate prospective cohort studies.

The authors used data from the Cardiovascular Health Study (CHS), Nurses’ Health Study (NHS), and Health Professionals Follow-Up Study (HPFS). Each of these three cohort studies represent distinct patient populations, which does influence the overall generalizability of these results. CHS is a prospective cohort study of adults aged 65 years and older. The NHS is a prospective cohort study of female registered nurses 30 to 55 years of age. Lastly, HPFS is a cohort study of U.S. male health professionals 40 to 75 years of age. Most participants in each study were white (88% in CHS, for example). The analysis of NHS and HPFS was based on a nested case-control study of age and vascular-risk factor matched controls. Ischemic stroke was subdivided into atherothrombotic, cardioembolic, or other. At the time of enrollment in the studies, blood samples were collected and stored for later analysis of omega-3 fatty acid levels. Of note, there were some differences in collection and storage of blood samples for fatty acid analysis between the three studies.

By |October 23rd, 2017|clinical, prevention|Comments Off on Omega-3 Fatty Acid Biomarkers: A Potential Marker of Incident Ischemic Stroke Risk?
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Readmission after Subarachnoid Hemorrhage

Pouya Tahsili-Fahadan, MD

Dasenbrock HH, Angriman F, Smith TR, Gormley WB, Frerichs KU, Aziz-Sultan MA, et al. Readmission After Aneurysmal Subarachnoid Hemorrhage: A Nationwide Readmission Database Analysis. Stroke. 2017

Readmission (within a pre-defined period of time from discharge) is frequently measured and reported as a quality measure for care provided by physicians and hospitals. However, it is debatable whether this measure is an appropriate quality metric for various indications and etiologies of the index hospitalization. Dasenbrock et al. investigated this question by analyzing the Nationwide Readmission Database (NRD) for readmission after aneurysmal subarachnoid hemorrhage (SAH).

Data from this longitudinal administrative database within 21 states were extracted for 3806 non-elective adult patients admitted for treatment of aneurysmal subarachnoid or intracerebral hemorrhage and discharged alive in 2013. Mortality during the index hospitalization and readmission were 11% and 1.7%, respectively, and about two thirds of survivors were discharged home. The median cost of the index and readmission hospitalizations were $266,304 and $45,091, respectively, and readmission was associated with increased total costs. Within the next 30 days from discharge, 10.2% of patients were readmitted with 34.4%, 65.6%, and 82.4% of readmissions within 1, 2, and 3 weeks from discharge, respectively. As expected, patients who were readmitted had higher SAH severity scale, higher incidence of cerebral edema, and complications during their index hospitalization, and were more likely to undergo tracheostomy or gastrostomy, and less likely to be discharged home. Treatment modality (clipping versus coiling) was not associated with increased rate of readmission. Independent predictors for readmission, however, were identified as comorbidity score equal or more than 3, higher SAH severity, and discharge destination other than home; the more predictors, the higher chance of readmission. Of note, high-volume institutions had lower risk of readmission and mortality. The most common reasons for readmission included hydrocephalus, other neurological complications, infections, and thromboembolic events. Neurosurgical procedures and surgeries were among the most common operations performed after readmission. Importantly, hydrocephalus during index hospitalization was associated with increased risk of readmission for hydrocephalus.

By |October 18th, 2017|clinical, hemorrhage|Comments Off on Readmission after Subarachnoid Hemorrhage
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