American Heart Association

Monthly Archives: October 2021

Article Commentary: “Deep Learning–Based Automated Thrombolysis in Cerebral Infarction Scoring”

Tolga D. Dittrich, MD

Nielsen M, Waldmann M, Frölich AM, Flottmann F, Hristova E, Bendszus M, Seker F, Fiehler J, Sentker T, Werner R. Deep Learning-Based Automated Thrombolysis in Cerebral Infarction Scoring: A Timely Proof-of-Principle Study. Stroke. 2021.

The success of mechanical thrombectomy is commonly measured by the TICI (Thrombolysis in Cerebral Infarction) score. The score is determined by the visual assessment of the digital subtraction angiography (DSA) images during the intervention by the treating interventionalist. Despite modifications of the original scale (e.g., modified TICI [mTICI]) that have become established in the meantime, a relatively high inter- and intraobserver variability of TICI scores can be observed. This investigator dependency poses a challenge, particularly regarding clinical studies, as it may affect the comparability of results.

In the present study, based on occlusions of the middle cerebral artery in the M1 segment, Nielsen and colleagues sought to develop an automated and thus more objective TICI assessment using a deep learning (DL) approach. Agreement between DL and expert-based assessment (gold standard) was evaluated, and a comparison with corresponding published numbers on expert assessment variability was performed.

By |October 29th, 2021|clinical|0 Comments

Efficacy of Tenecteplase as a Reperfusion Therapy for Acute Ischemic Stroke

Farah Aleisa, MD

Burgos AM, Saver JL. Evidence that Tenecteplase Is Noninferior to Alteplase for Acute Ischemic Stroke: Meta-Analysis of 5 Randomized Trials. Stroke. 2019;50:2156–2162.

Tenecteplase (TNK) is a tissue-type plasminogen activator modified by 3 amino acids from alteplase, and it has the potential to reperfuse brain tissue in case of blocked brain vessels. It has greater fibrin specificity resulting in lower bleeding risks,1 and it has initial serum half-life of 20 minutes and a mean terminal half-life of 100 minutes, such that it can be given as a bolus dose on a weight-adjusted basis,2 being given even in the pre-hospital setting, which allows faster time to reperfusion and less delay for endovascular therapy if needed.

There are 5 independent randomized trials that have studied the efficacy of TNK in comparison to altelplase (ALT) in acute ischemic stroke.3-7 These trials enrolled a total of 1585 patients (828 TNK, 757 ALT), mean National Institutes of Health Stroke Scale (NIHSS) at baseline was 7, and mean time from last known well to treatment start was 148 minutes. All patients with ALT received standard 0.9 mg/kg dosing; TNK dosing was one-time bolus only, at doses of 0.1 mg/kg in 6.8% of patients, 0.25 mg/kg in 24.6%, and 0.4 mg/kg in 68.6%.

By |October 26th, 2021|clinical|0 Comments

Chasing the D-Dimer Level in Patients With ESUS

Muhammad Rizwan Husain, MD
@RIZWANHUSAINMD

Choi KH, Kim JH, Kim JM, Kang KW, Lee C, Kim JT, Choi SM, Park MS, Cho KH. d-dimer Level as a Predictor of Recurrent Stroke in Patients With Embolic Stroke of Undetermined Source. Stroke. 2021;52:2292–2301.

D-dimer levels are known to be a marker for underlying hypercoagulable state in several studies reporting raised D-dimer levels in patients with cardioembolic stroke, underling malignancy, and venous thromboembolism. However, the role of D-dimer levels to predict recurrent stroke in patients with ESUS (Embolic Stroke of Undetermined Source) is unknown.

The authors in this study evaluated the role of plasma D-dimer levels to help predict recurrent stroke (ischemic or hemorrhagic) within 1 year in patients with ESUS, as well as to evaluate possible etiologies of recurrent strokes based on D-dimer levels.

Article Commentary: “Rescue of Neglect and Language Impairment After Stroke Thrombectomy”

Hannah Roeder, MD, MPH

Desai SM, Malhotra K, Ramaiah G, Tonetti DA, Haq W, Jovin TG, Jadhav AP. Rescue of Neglect and Language Impairment After Stroke Thrombectomy. Stroke. 2021.

The presence of cortical signs, such as aphasia and neglect, on a stroke code examination prompts neurologists to investigate for the presence of a large vessel occlusion (LVO) and to determine if the patient may benefit from thrombectomy. Can the rescue or persistence of cortical signs following mechanical thrombectomy (MT) help us predict outcomes among stroke patients?

The authors performed a retrospective analysis of the stroke database at a single Comprehensive Stroke Center to assess the impact of neglect and aphasia on clinical outcomes for patients with right and left anterior LVO, respectively. They found that a significant majority of patients with right-sided LVOs presented with neglect (71%) and patients with left-sided LVOs presented with language impairment (93%). MT resulted in “rescue of neglect” (31%) and “rescue of language impairment” (23%) in a minority of cases but was an independent and better predictor of functional independence (mRS 0-2) and survival even after adjustment for NIHSS and infarct volume.

By |October 22nd, 2021|clinical|0 Comments

Activation of T Lymphocytes After Stroke: An Antigen-Specific or Antigen-Independent Mechanism?

Aurora Semerano, MD
@semerano_aurora

Schulze J, Gellrich J, Kirsch M, Dressel A, Vogelgesang A. Central Nervous System-Infiltrating T Lymphocytes in Stroke Are Activated via Their TCR (T-Cell Receptor) but Lack CD25 Expression. Stroke. 2021;52:2939–2947.

Leukocytes from peripheral circulation infiltrate the ischemic brain within hours to days after stroke, and they can contribute to secondary tissue damage, as well as to the subsequent processes of repair and recovery. T lymphocytes are also implied in this response. However, it remains unclear which mechanism of lymphocyte activation plays the most relevant role after stroke: Indeed, both antigen-specific T lymphocytes (reacting against brain antigens) and antigen-independent mechanisms (driven by pro-inflammatory mediators) have been described. These previous studies were mostly conducted with ablative approaches, that’s to say in T-cell-deficient experimental models or upon inhibition of lymphocyte infiltration into the brain.

Antithrombotic Regimen for Stroke Patients: Where to Draw the Line?

Wern Yew Ding, MBChB

Li ZX, Xiong Y, Gu HQ, Fisher M, Xian Y, Johnston SC, Wang YJ. P2Y12 Inhibitors Plus Aspirin Versus Aspirin Alone in Patients With Minor Stroke or High-Risk Transient Ischemic Attack. Stroke. 2021;52:2250–2257.

Patients with ischemic stroke or transient ischaemic attack (TIA) are at risk of further events. Previously, these patients were treated with single antiplatelet therapy. However, contemporary guidelines recommend that dual-antiplatelet therapy (DAPT) may be considered in the acute phase: the duration of treatment depending on stroke severity. Several studies have investigated the use of different DAPT regimens in patients with minor stroke or high-risk TIA.

In this study by Li and colleagues, the authors undertook a systematic review and meta-analysis of 4 randomized controlled trials that included a total of 21493 patients with acute minor stroke (NIHSS score ≤3/≤5) or high-risk TIA (ABCD2 ≥4/≥6) who were randomized to receive either DAPT or aspirin alone within 24 hours of symptom onset. Three of the 4 studies used clopidogrel while the remaining study investigated the use of ticagrelor. The authors reported that DAPT reduced the risk of stroke recurrence by 24%. However, there was no statistical difference in all-cause mortality between the groups, and those on DAPT were exposed to a 2.2-fold greater risk of moderate or severe bleeding.

Proportional Recovery and Health-Related Quality of Life Outcomes

Melissa Bailey, MD

Lin C, Martin K, Arevalo Y, Harvey R, Prabhakaran S. Association of Proportional Recovery After Stroke with Health-Related Quality of Life. Stroke. 2021;52:2968–2971.

When anticipating the degree of recovery after stroke, motor deficit improvement has been well predicted by the proportional recovery rule. Post-stroke, many patients will regain 70% of the motor function that was lost, though this number often does not apply to those with severe initial deficits. However, return to prior motor functioning is only part of the recovery process, and measures of quality of life after stroke are also important in understanding a patient’s return to functionality after stroke. In a study by Lin et al., the authors sought to investigate whether achieving the 70% proportional recovery threshold was associated with improved health-related quality of life scores.

Mobile Stroke Units in the Management of Intracerebral Hemorrhage

Andrew Micieli, MD

Cooley SR, Zhao H, Campbell BCV, Churilov L, Coote S, Easton D, Langenberg F, Stephenson M, Yan B, Desmond PM, et al. Mobile Stroke Units Facilitate Prehospital Management of Intracerebral Hemorrhage. Stroke. 2021.

The phrase “time is brain” refers to the rapid identification and potential administration of reperfusion therapy (thrombolysis and/or endovascular therapy) in the setting of ischemic stroke. However, this phrase is also applicable to intracerebral hemorrhage (ICH). At the present time, treatment of ICH is targeted at early diagnosis with neuroimaging followed by therapy targeted at preventing hematoma expansion. This includes early lowering of blood pressure, reversal of coagulopathy or anticoagulation, critical care management and potential surgical options. Time is critical, as hematoma expansion is a strong determinant of neurological deterioration and worse clinical outcomes. This treatment paradigm lends itself well to the mobile stroke unit (MSU).

By |October 13th, 2021|clinical|0 Comments

Stroke in the COVID-19 Era

Kevin O’Connor, MD

Katsanos AH, Palaiodimou L, Zand R, Yaghi S, Kamel H, Navi BB, Turc G, Benetou V, Sharma VK, Mavridis D, et al. Changes in Stroke Hospital Care During the COVID-19 Pandemic: A Systematic Review and Meta-Analysis. Stroke. 2021.

COVID-19 complicates many aspects of clinical care, including care of stroke patients. Katsanos et al. conducted a meta-analysis on the impact of COVID-19 on the provision of stroke care, independent of SARS-CoV-2 infection status. They collected 46 studies capturing data from 129,491 patients across Africa, Asia, Europe, and the Americas comparing common stroke care variables pre- and post-pandemic onset. These included demographic information, vascular risk factors, intravenous thrombolysis (IVT) administration, endovascular thrombectomy (EVT) performance, relevant time metrics, and hospitalization outcomes.

Article Commentary: “Endovascular Thrombectomy for Treatment of Acute Ischemic Stroke During Pregnancy and the Early Postpartum Period”

Ericka Teleg, MD

Dicpinigaitis AJ, Sursal T, Morse CA, Briskin C, Dakay K, Kurian C, Kaur G, Sahni R, Bowers C, Gandhi CD, et al. Endovascular Thrombectomy for Treatment of Acute Ischemic Stroke During Pregnancy and the Early Postpartum Period. Stroke. 2021.

This study begins with emphasizing the lack of evidence in the management of pregnant patients or those in the early postpartum period confronted with acute ischemic stroke within the time window for endovascular therapy. In the advent of the landmark clinical trials on the benefit of endovascular therapy for acute ischemic stroke, it is the authors’ hypothesis that this particular group will also show a favorable clinical course and short-term outcomes likened to those found in the general population. Pregnant and postpartum women were systematically excluded from the clinical trials in acute reperfusion therapies for acute ischemic stroke. Acute reperfusion therapy with endovascular thrombectomy in the setting of pregnancy and the postpartum period is an important area to navigate. Pathophysiology of stroke among this population includes a hypercoagulable physiological state. It is important that this study answers this need in terms of benefit, complications, and outcomes, as stroke physicians are bound to encounter these complex cases in their lifetime.