Friday, July 1, 2016

Higher Admission Heart Rate Associated with Death and Poor Functional Outcome in ICH

Alexander E. Merkler, MD

Qiu M, Sato S, Zheng D, Wang X, Carcel C, Hirakawa Y, et al. Admission Heart Rate Predicts Poor Outcomes in Acute Intracerebral Hemorrhage: The Intensive Blood Pressure Reduction in Acute Cerebral Hemorrhage Trial Studies. Stroke. 2016

Intracerebral hemorrhage is a devastating disease with a one-month mortality of 40%. Larger ICH volume, older age, and hematoma expansion are some of the factors associated with both poor functional outcome and death. Admission heart rate (HR) has previously been shown to predict higher mortality in coronary artery disease and ischemic stroke, but its impact on patients with ICH is unknown. 

Thursday, June 30, 2016

Elevated Blood Pressure Significantly Associated with Risk of Vascular Dementia

Danny R. Rose, Jr., MD

Vascular dementia is the second most common cause of dementia, but many aspects of the disease are poorly understood. In particular, there is conflicting evidence regarding the relationship between blood pressure and vascular dementia. Elevated blood pressure in midlife has been found to have a positive association with future development of dementia, but several other studies have found low blood pressure in old age to be associated with an increased risk of dementia. One possible explanation of these findings is that it represents “reverse causality,” meaning vascular dementia is responsible for low blood pressure by decreasing sympathetic drive. Blood pressure medication may also play a confounding role in this association. Emdin et al. sought to further clarify this association by conducting an analysis of 4.28 million individuals without vascular disease or dementia, supplemented with an analysis of a prospective population-based cohort of patients with TIA and stroke.

Wednesday, June 29, 2016

Blood Biomarkers in Ischemic Stroke

Ilana Spokoyny, MD

Blood biomarkers are an active research interest, with the potential for predicting ischemic stroke via identification of novel risk pathways. The authors of this paper tested the associations between ischemic stroke and three blood markers: procalcitonin (PCT), copeptin, and midregional-pro-atrial natriuretic peptide (MRproANP). These biomarkers were chosen because they represent three different pathophysiological processes. Procalcitonin is associated with bacterial infections and was chosen with the hope of finding a link between infection and ischemic (especially non-cardioembolic) stroke. Copeptin is a hypothalamic stress hormone, which was chosen because chronic activation of the hypothalamic-pituitary-adrenal axis and the sympathetic nervous system may promote vascular risk factors. MRproANP was hypothesized to be a marker of hemodynamic dysfunction and thereby a potential marker of (especially cardioembolic) stroke.

Monday, June 27, 2016

Relevance of Carotid Plaque Characteristics for Ischemic Stroke and Coronary Heart Disease

Citing the systemic nature of atherosclerosis, the authors of this paper studied the association between extracranial carotid atherosclerosis features and prior ischemic stroke (IS) and coronary heart disease (CHD). 

Patients were selected from the Rotterdam Study. Participants with at least 2.5mm of carotid intima media thickness (IMT) were eligible for this study. Of 3,795 eligible participants, 1,982 underwent MRI of bilateral carotid arteries. MRI was performed on 1.5-Tesla scanners with a carotid artery protocol. All plaques of at least 2mm of thickness were assessed for intraplaque hemorrhage (IPH), lipid core, and calcification. Additionally, wall thickness and degree of stenosis were determined. Participants’ history was queried for prior IS and CHD (non-fatal MI or myocardial revascularization). Covariates were age, sex, smoking status, lipid measurements, BMI, diabetes, and hypertension.

Friday, June 24, 2016

Intracranial Atherosclerosis and Coronary Atherosclerosis: Two Twigs from the Same Vascular Branch

Peggy Nguyen, MD

Chung J-W, Bang OY, Lee MJ, Hwang J, Cha J, Choi J-H, et al. Echoing Plaque Activity of the Coronary and Intracranial Arteries in Patients With Stroke. Stroke. 2016

Atherosclerosis is a diffuse process that can affect both the coronary and carotid arteries, but while previous studies have suggested a strong correlation between coronary atherosclerosis and extracranial carotid atherosclerosis, the correlation with intracranial atherosclerosis is less clear. Whereas the mechanism of myocardial infarction from coronary atherosclerosis is likely more similar to ischemic stroke caused by extracranial atherosclerosis, ischemic stroke caused by intracranial atherosclerosis typically falls into two etiologies: branch occlusive disease-type (B-type), where atherosclerosis occludes a perforating artery, versus coronary-type plaque rupture of plaque (C-type), where the atherosclerotic plaque ruptures, causing a shower of multiple embolic infarcts distally. This study attempts to characterize intracranial plaque phenotypes and correlate asymptomatic coronary artery disease (CAD) with intracranial atherosclerotic disease (ICAD) burden.

Thursday, June 23, 2016

PCI Setting Has Little Effect on Post-Stroke Cardiovascular Outcomes and Mortality

Benjamin Kummer, MD

Myint PK, Kwok CS, Roffe C, Kontopantelis E, Zaman A, Berry C, et al. Determinants and Outcomes of Stroke Following Percutaneous Coronary Intervention by Indication. Stroke. 2016.

Percutaneous coronary intervention (PCI) is infrequently complicated by stroke, which tends to occur more frequently after emergent PCI, and is highly morbid when it occurs. However, the relationship between PCI setting (emergent vs. elective) or stroke subtype (ischemic vs. hemorrhagic) and stroke risk factors, as well as post-PCI stroke outcomes, remains unclear. Myint et al. sought to address these gaps in knowledge by studying approximately 560,000 PCI patients from the British Cardiovascular Intervention Society database, using in-hospital major adverse cardiovascular events (MACE) and 30-day mortality as outcomes.

Tuesday, June 21, 2016

Residual Arterial Stenosis after Endovascular Thrombectomy: a Relationship with in Situ Thrombo-occlusion and Reocclusion Rates

Mark R. Etherton, MD, PhD

The advent of efficacious endovascular thrombectomy (EVT) for ischemic stroke secondary to acute occlusion of proximal anterior circulation vessels has allowed for the characterization of occlusive lesions. Understanding the underlying pathology of these occlusive lesions could be informative for predicting the success of the endovascular intervention as well as prognostication of clinical outcomes.

Friday, June 10, 2016

Inverse Relationship between HDL2-C Subfraction and Carotid Intima-Media Thickness

Alexander E. Merkler, MD 

Increased carotid-intima media thickness (cIMT) is associated with future cerebrovascular events. Although previous data has shown an inverse relationship between high density lipoprotein cholesterol (HDL-C) and future cerebrovascular events, this association has been challenged in recent trials; therefore, it is uncertain whether HDL-C subfractions have differential effects on cerebrovascular risk.