American Heart Association

Are Topographical Patterns of Microbleeds Enough to Determine a Difference Between Amyloid and Hypertensive Angiopathy?

Alejandro Rodríguez-Vázquez, MD

Jung YH, Jang H, Park SB, Choe YS, Park Y, Kang SH, Lee JM, Kim JS, Kim J, Kim JP, et al. Strictly Lobar Microbleeds Reflect Amyloid Angiopathy Regardless of Cerebral and Cerebellar Compartments. Stroke. 2020;51:3600–3607.

Nowadays, Boston criteria are pillars for the diagnosis of cerebral amyloid angiopathy (CAA). According to those criteria, CAA diagnosis is excluded due to the presence of deep microbleeds independent of other neuroimaging findings and in absence of pathology. However, Thal et al. proposed that CAA pathology extends sequentially from cortical to cerebellar and finally basal ganglia and brainstem vessels. Therefore, deep microbleeds added to lobar both cerebral and cerebellar ones do not exclude CAA but are related to an advanced stage of the disease.

In this study, the authors tried to determine if the topographical pattern of microbleeds could help to establish the underlying pathophysiology comparing amyloid-β burden and cerebral small vessel disease markers according to the anatomic distribution of microbleeds. From 2333 patients who visited the authors’ memory clinic, they included 71 with suspected CAA markers on MRI neuroimaging, and they categorized them in 4 groups based on the distribution of microbleeds: strictly lobar (n=33); strictly lobar cerebral and strictly lobar cerebellar (n=13); lobar, cerebellar both lobar and dentate and deep (n=17); and lobar and deep (n=7). Brainstem microbleeds were categorized as deep. In addition, they performed an amyloid-β PET and a complete cognitive assessment. The prevalence of hypertension was slightly higher on the lobar and deep group than in the strictly lobar, but the rest of classic cardiovascular risk factors and dementia did not significantly differ between groups.

By |April 21st, 2021|clinical|0 Comments

Stroke and COVID-19 Infection: Causation or Correlation?

Ying Gue, PhD
@DrYXGue

Dhamoon MS, Thaler A, Gururangan K, Kohli A, Sisniega D, Wheelwright D, Mensching C, Fifi JT, Fara MG, Jette N, et al. Acute Cerebrovascular Events With COVID-19 Infection. Stroke. 2021;52:48–56.

In this article, Dhamoon et al. compared the differences in characteristics and outcomes of patients, with and without concurrent coronavirus disease 2019 (COVID-19) infection, who presented with stroke during the peak of the COVID-19 pandemic in New York City. The retrospective observational study identified a total of 277 patients, of which 105 (38%) were COVID-19 positive.

Interestingly, patients with COVID-19 who suffered an acute cerebrovascular event were more likely males (61.9% vs. 46.1% P=0.038) with no history of smoking (28.3% vs. 47.1%, P=0.014) and less likely to be taking full-dose anticoagulant at stroke onset (68.6% vs. 90.7%, P<0.0001). Many studies have shown that males with COVID-19 are associated with more adverse events and complications, and, hence, this finding was not surprising. Secondly, COVID-19 infection is associated with a pro-thrombotic state, and, therefore, the lack of traditional cardiovascular risk factor (such as smoking) is probable. As the authors pointed out, failure of data captured on admission due to a higher proportion of patients being more critically ill could also explain the lower proportion of smokers.

By |April 21st, 2021|clinical|0 Comments

A Good Reminder: Adherence to Quality Indicators Associated with Decreased 7-Day Mortality

Melanie R. F. Greenway, MD
@MRFGreenwayMD

Haas K, Rücker V, Hermanek P, Misselwitz B, Berger K, Seidel G, Janssen A, Rode S, Burmeister C, Matthis C, et al. Association Between Adherence to Quality Indicators and 7-Day In-Hospital Mortality After Acute Ischemic Stroke. Stroke. 2020;51:3664–3672.

In the age of checklists, quality metrics, and frequent audits, sometimes the importance of these indicators is taken for granted. Instead of serving as a guiding light for quality care, they may be seen as an annoyance, slowing down an already inefficient system. This study reviewing the association between quality indicators (QI) and outcomes is a good reminder of the importance of tending to these quality indicators. 

This study utilized the German Stroke Registers Study Group (Arbeitsgemeinschaft Deutschprachiger Schlaganfall Register), which is a network of nine stroke registers, comprising multiple regions throughout the country. 388,012 patients with acute ischemic stroke admitted to 736 hospitals were reviewed from 2015-2016. Of the hospitals participating, 55.6% of them had stroke unit services. Overall, 7-day in-hospital mortality was 3.4%, and median length of stay was 8 days. 

Managing Tandem Occlusions From Carotid Dissection: To Stent or Not to Stent?

Setareh Salehi Omran, MD

Marnat G, Lapergue B, Sibon I, Gariel F, Bourcier R, Kyheng M, Labreuche J, Dargazanli C, Consoli A, Blanc R, et al. Safety and Outcome of Carotid Dissection Stenting During the Treatment of Tandem Occlusions: A Pooled Analysis of TITAN and ETIS. Stroke. 2020;51:3713–3718.

Intracranial occlusions with an ipsilateral cervical internal carotid artery (ICA) stenosis/occlusion, so-called tandem occlusions, are a frequent cause of anterior circulation strokes. Tandem occlusions can be treated with endovascular therapy, although the best technical strategy for treating the ICA stenosis/occlusion component is unclear.1 In particular, there is great variability in practice with performing carotid artery stenting (CAS) in addition to intracranial thrombectomy.2 It is also unknown whether the etiology of the ICA stenosis/occlusion, either from dissection or atherosclerosis, should impact the decision to perform CAS. While data supports thrombectomy with CAS in tandem occlusions due to atherosclerosis, there is limited data on its safety and efficacy in tandem occlusions from carotid dissection.3

Marnat et al4 examined the safety and outcome of CAS during the treatment of tandem occlusions from carotid dissections using pooled data from two prospectively maintained, multicenter databases (Endovascular Treatment in Ischemic Stroke and Thrombectomy in Tandem Lesion). The analysis included patients who received endovascular therapy for tandem occlusions related to acute cervical carotid dissection between January 2012 and January 2019. The endovascular strategy, stenting protocol, and antithrombotic regimens were chosen by the interventionalist and treating team. Patients were divided in two groups depending on whether they did or did not undergo CAS. The main outcomes of favorable neurological outcome (defined as 90-day mRS 0-2) and successful reperfusion (modified Thrombolysis in Cerebral Infarction score 2b-3) were assessed in both groups. The rates of procedural complications, 90-day mortality, and symptomatic intracerebral hemorrhage were also compared between patients who did and did not undergo CAS. In order to minimize potential bias due to endovascular strategy, the authors performed a sensitivity analysis comparing main clinical outcomes (favorable outcome and overall degree of disability) in the subgroup of patients with successful reperfusion.

Left Atrial Appendage Thrombus in Patients with Ischemic Stroke as Marker of Atrial Fibrillation?

Wern Yew Ding, MBChB

Senadeera SC, Palmer DG, Keenan R, Beharry J, Yuh Lim J, Hurrell MA, Mouthaan P, Fink JN, Wilson D, Lim A, Wu TY. Left Atrial Appendage Thrombus Detected During Hyperacute Stroke Imaging Is Associated With Atrial Fibrillation. Stroke. 2020;51:3760–3764.

Atrial fibrillation (AF) is an established risk factor for thromboembolic events, including ischemic stroke. Therefore, identification of patients with this arrhythmia is important to facilitate the implementation of stroke prevention therapy using oral anticoagulation. Nonetheless, as a significant proportion of patients with AF remain asymptomatic, it remains largely under-diagnosed in the general population. Given that the source of emboli in the majority of AF-related strokes originates from the left atrial appendage (LAA), inclusion of this structure in imaging protocols may have a role in aiding the diagnosis of AF.

In a recent retrospective study of consecutive patients with ischemic stroke or transient ischemic attack, Senadeera and colleagues investigated the prevalence of computed tomography angiography (CTA)-detected LAA thrombus during hyperacute stroke imaging and evaluated the association between LAA thrombus and AF. The imaging protocol consisted of non-contrast CT, followed by CT perfusion and CTA from aortic arch to vertex. Two experienced physicians and pre-defined measures were used to assess for LAA thrombus on these scans.

External Validation of the Edinburgh Criteria for Cerebral Amyloid Angiopathy

Walter Valesky, MD

van Etten ES, Kaushik K, van Zwet EW, Voigt S, van Walderveen MAA, van Buchem MA, Terwindt GM, Wermer MJH. Sensitivity of the Edinburgh Criteria for Lobar Intracerebral Hemorrhage in Hereditary Cerebral Amyloid Angiopathy. Stroke. 2020;51:3608–3612.

Limitations in our knowledge of cerebral amyloid angiopathy (CAA) persist due to relatively small study sample sizes and a requirement for pathological specimens to confirm a diagnosis. The Edinburgh criteria is the most recent decision instrument developed to assist in the pre-mortem diagnosis of this disorder. In their logistic regression model, Rodrigues et al. utilized genetic factors (APOE ε4 genotype) and computed tomography (CT) findings (finger-like projections and subarachnoid hemorrhage) to attain a high degree of sensitivity and specificity.1 However, their cohort relied on autopsy specimens for confirmation of moderate-to-severe CAA. 

To this end, van Etten et al. recruited patients with Dutch-type CAA (D-CAA) for analysis. D-CAA, a hereditary variant of CAA, causes similar radiographic features as CAA with an accelerated clinical course, and most importantly, does not require a tissue-based confirmation. Using patients with D-CAA, the investigators evaluated the aforementioned CT variables in this validation study. 

Interventions for Medium Vessel Occlusions

Kevin O’Connor, MD

Pérez-García C, Moreu M, Rosati S, Simal P, Egido JA, Gomez-Escalonilla C, Arrazola J. Mechanical Thrombectomy in Medium Vessel Occlusions: Blind Exchange With Mini-Pinning Technique Versus Mini Stent Retriever Alone. Stroke. 2020;51:3224-3231.

Although mechanical thrombectomy (MT) is routinely performed for patients with acute stroke due to large vessel occlusions, interventions for those with medium vessel occlusions (MeVO) are increasing. Techniques for MT for MeVOs include the use stent retrievers and distal aspiration catheters (DACs). A recently developed approach is the blind exchange/mini-pinning (BEMP) technique, which combines a mini stent retriever with a DAC (see Figure 1 below).

Figure 1. Illustrations depicting the blind exchange with mini-pinning technique.
Figure 1. Illustrations depicting the blind exchange with mini-pinning technique.

Pérez-García et al. retrospectively compared mini stent retrievers alone (initial standard institutional MeVO procedure, n=50) versus the BEMP technique (later standard institutional MeVO procedure, n=56) for effectiveness and safety using a prospective database of MT patients. Aside from the DACs, the devices used for the two groups were comparable. The BEMP technique group had a higher rate of expanded Thrombolysis in Cerebral Ischemia (eTICI) 2c/3 recanalization scores after first pass (n=32, 57% versus n=17, 34%; P=0.017) and at procedure conclusion (n=37, 66% versus n=23, 46%; P=0.037). The rate of eTICI ≥ 2b recanalization scores was comparable between the groups after first pass (n=36, 64% versus n=25, 50%; P=0.137) and at procedure end (n=44, 78.5% versus n=39, 78%; P=0.856). A rescue therapy (other than the initial technique) was used less often in the BEMP group (n=4, 7.1% versus n=11, 22%; P=0.028). The BEMP technique was an independent predictor of eTICI 2c/3 recanalization (OR 2.72 [95% CI, 1.19-6.22]; P=0.018).

Medium Vessel Occlusion: How Far is Enough?

Elena Zapata-Arriaza, MD
@ElenaZaps

Ospel JM, Menon BK, Demchuk AM, Almekhlafi MA, Kashani N, Mayank A, Fainardi E, Rubiera M, Khaw A, Shankar JJ, et al. Clinical Course of Acute Ischemic Stroke Due to Medium Vessel Occlusion With and Without Intravenous Alteplase Treatment. Stroke. 2020;51:3232-3240.

There is enough scientific evidence to employ endovascular treatment (EVT) for acute ischemic stroke (AIS) caused by large vessel occlusion (LVO). However, in the case of Medium Vessel Occlusion (MeVO), there are still gaps in knowledge in terms of safety and efficacy that must be clarified to indicate EVT in these occlusions. In order to determine the clinical course of acute ischemic stroke due to MeVO with and without intravenous alteplase treatment, Ospel and colleagues performed the following study.

Patients with MeVO (M2/M3/A2/A3/P2/P3 occlusion) from the INTERRSeCT and PRoveIT studies were included. Baseline characteristics and clinical outcomes were summarized using descriptive statistics. The primary outcome was a modified Rankin Scale score of 0 to 1 at 90 days. Secondary outcomes were the common odds ratio for a 1-point shift across the modified Rankin Scale and functional independence (modified Rankin Scale score 0-2). The authors compared outcomes between patients with versus without intravenous alteplase treatment and between patients who did and did not show recanalization on follow-up computed tomography angiography.

By |April 15th, 2021|clinical|0 Comments

Collaterals Impact on Ischemic Area: Does the Size Matter?

Elena Zapata-Arriaza, MD
@ElenaZaps

Al-Dasuqi K, Payabvash S, Torres-Flores GA, Strander SM, Nguyen CK, Peshwe KU, Kodali S, Silverman A, Malhotra A, Johnson MH, et al. Effects of Collateral Status on Infarct Distribution Following Endovascular Therapy in Large Vessel Occlusion Stroke. Stroke. 2020;51:e193–e202.

Collateral status has been related to impact on infarct size after ischemic stroke (IS) recanalization. However, the smaller final infarct size is not always related to a good clinical situation, which seems to be related to the eloquence of the affected area, rather than the volume of the ischemic area itself. The present scientific work aims to evaluate the relation between collateral status and reperfusion degree on final infarct distribution and clinical outcome after IS due to large vessel occlusion (LVO).

Al-Dasuqi and colleagues performed a single center retrospective analysis of all patients with LVO who were treated with endovascular treatment between 2013-2019. The authors collected clinical, demographic and radiological data. They applied a multivariate voxel-wise general linear model to correlate the distribution of final infarction with collateral status and degree of reperfusion. Early favorable outcome was defined as a discharge modified Rankin Scale score ≤2.

The Benefit of Targeting LDL Cholesterol <70 mg/dL Even at Expense of Adding Second Lipid-Lowering Agent

Manya Khrlobyan, DO, MS

Amarenco P, Kim JS, Labreuche J, Charles H, Giroud M, Lee BC, Mahagne MH, Nighoghossian N, Steg PG, Vicaut E, et al. Benefit of Targeting a LDL (Low-Density Lipoprotein) Cholesterol <70 mg/dL During 5 Years After Ischemic Stroke. Stroke. 2020;51:1231–1239.

The most recent American Heart Association/American Stroke Association guidelines recommend high intensity statin therapy for patients with ischemic stroke or TIA presumed to be of atherosclerotic origin and a Low-Density Lipoprotein (LDL) level >100 mg/dL. These recommendations are largely based on the results of the 2006 SPARCL trial (Stroke Prevention by Aggressive Reduction in Cholesterol Level). With these recommendations in mind, patients are typically started on Atorvastatin 80 mg daily, though often times without a specific LDL target in mind.

The TST trial (Treat Stroke to Target) was a randomized, event driven trial which investigated the benefit of targeting an LDL of <70 mg/dL in ischemic stroke patients in a French and Korean population to reduce the risk of cardiovascular events. Patients were eligible if they had an ischemic stroke <3 months previously or a TIA within the previous 15 days, atherosclerotic stenosis of cerebral vasculature (extra or intracranial), aortic arch plaque >4 mm, or known history of coronary artery disease. Patients were randomly assigned in a 1:1 ratio to target LDL of < 70 mg/dL or target LDL of 100 + 10 mg/dL. Investigators were free to use any type and dose of statin to reach the target LDL and, at 3 weeks follow-up, had an option of adjusting the statin dose or adding other lipid lowering agents such as ezetimibe to achieve the target LDL. The primary endpoint was the composite of ischemic stroke, myocardial infarction, need for carotid or coronary revascularization, and unexplained sudden death.