American Heart Association

Monthly Archives: November 2021

Using Post-Thrombectomy CT Perfusion to Improve Tissue Reperfusion Assessments

Vignan Yogendrakumar, MD, MSc
@VYogendrakumar

Tan Z, Parsons M, Bivard A, Sharma G, Mitchell P, Dowling R, Bush S, Xu A, Yan B. Optimal Tissue Reperfusion Estimation by Computed Tomography Perfusion Post-Thrombectomy in Acute Ischemic Stroke. Stroke. 2021.

In the thrombectomy era of acute stroke care, it is commonplace to utilize mTICI scores as one of the primary measures of assessing reperfusion status immediately post-procedure. In many studies, it is common to see a measure of mTICI scores 2b-3 as a representation of a good study outcome. However, registry data shows us that mTICI 2b scores are associated with an independent functional state in only 40% of patients. While the surrogate use of mTICI status to represent tissue reperfusion status is certainly a reasonable approach, the association between mTICI score and actual tissue status remains unclear.

In this study by Tan and colleagues, acute stroke patients treated at the Royal Melbourne Hospital with endovascular clot retrieval underwent CT or MRI perfusion at 24-36 hours post procedure. Comparing the baseline and follow-up perfusion scans, the authors defined optimal tissue reperfusion (TOR) as a >90% reduction of penumbra (using TMax>6s) volume. In 82 patients, those who had higher mTICI scores were more likely to achieve TOR at follow-up. Notably, achieving mTICI scores of 2c or 3 were more likely to be associated with TOR compared to mTICI 2b. Clinically, TOR was associated with improved clinical outcomes in multivariable logistic regression models.

By |November 9th, 2021|clinical|0 Comments

World Stroke Congress: “Stroke in Low to Middle Income Countries”

Ericka Samantha Teleg, MD

World Stroke Congress
October 28–29, 2021

Plenary Session: “Stroke in Low to Middle Income Countries”

While the landscape of stroke changes in terms of innovations, pathways and technology, there is a continuing increase of stroke burden in the low to middle income countries (LMICs). This session was moderated by Dr. Norlinah Ibrahim and Dr. Mayowa Owolabi.

Dr. Owolabi opened the discussion by giving an overview of the Lancet Commission in giving evidence-based recommendations that are pragmatic in nature extending to primary, secondary, and tertiary prevention, keeping in mind that these regions bear a burden due to limited resources. He emphasized the Stroke Quadrangle that includes epidemiological surveillance, acute care, rehabilitation, palliative care, health promotion, and disease prevention. He set the stage by reiterating that there is scarcity of funding for primary stroke prevention, particularly in LMICs. There is indeed an absence of an integrative approach. Regional and national differences in policymaking are also a variable. 

ASPECTS Score as a Biomarker to Predict Clinical Outcome

Arooshi Kumar, MD

Liebeskind DS, Saber H, Bhuva P, Xiang B, Yoo AJ, Jadhav AP, Haussen DC, Budzik RF, Bonafe A, Yavagal DR, et al. Serial ASPECTS in the DAWN Trial: Infarct Evolution and Clinical Impact. Stroke. 2021;52:3318–3324.

With the rapid adoption of endovascular therapy (EVT) for selected ischemic stroke patients, there remains a need to identify practical biomarkers to help predict treatment efficacy and clinical outcomes. The Alberta Stroke Program Early CT Score (ASPECTS) grading system is a well-accepted method to capture the degree of brain injury following stroke in the anterior circulation.1,2 While it has emerged as one standard method to quantify degree of ischemia and select candidates for endovascular treatment (EVT), the utility of post-intervention ASPECTS scores remains unclear.

To that end, a secondary SWIFT analysis demonstrated that post-treatment ASPECTS score was a reliable predictor of 90-day clinical function after stroke for presenting in the early intervention window (< 6hours).3 This study aimed at investigating the relevance of post-treatment ASPECTS score for later presenting window (6-24 hours) patients with ischemic stroke using the DAWN trial results. In this study, the ASPECTS score, initial and after 24 hours, was tabulated from 81 CT-CT pairs, 56 CT-MRI pairs, and 66 MRI-MRI pairs.

Article Commentary: “d-dimer Level as a Predictor of Recurrent Stroke in Patients With Embolic Stroke of Undetermined Source”

Meghana Srinivas, MD
@SrinivasMeghana

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.

Embolic stroke of underdetermined source is used to identify patients with nonlacunar embolic cryptogenic strokes with a more restrictive inclusion criteria for strokes of cryptogenic origin and complete diagnostic workup in comparison to classic cryptogenic strokes.

Patients with a diagnosis of ESUS at the time of their index stroke carry a high risk of recurrent strokes, which is approximately twice as compared to cryptogenic stroke other than ESUS. Given this incidence, it is important to identify the underlying mechanism and cause of strokes for secondary stroke prevention. Although the most common mechanism in ESUS is embolism with covert atrial fibrillation being the most common cause, recent randomized control trials have shown that non-vitamin antagonist oral anticoagulants (OACs) are not superior to aspirin in preventing recurrence of strokes in patients with ESUS. This can be explained by the heterogeneity among the potential causes of ESUS, which can be covert AF and hidden malignancy to patients with ipsilateral carotid stenosis of less than 50% and aortic arch atherosclerosis. As in the name, it is unknown at least at the time of initial presentation. It is important to identify factors which can predict the risk of recurrent stroke in patients with ESUS and use the right secondary preventative measures.

Post-Stroke Epilepsy in Children

Kevin O’Connor, M.D.

Sundelin HEK, Tomson T, Zelano J, Söderling J, Bang P, Ludvigsson JF. Pediatric Ischemic Stroke and Epilepsy: A Nationwide Cohort Study. Stroke. 2021.

Post-stroke epilepsy is a well-known entity, particularly in adults. To explore post-stroke epilepsy in children, Sundelin et al. used the Swedish National Registers to identify 1220 children with ischemic stroke (including cerebral venous sinus thrombosis, which could not be differentiated in the Register) and 12155 comparators between 1969-2016; they excluded patients with previously known epilepsy.

Of the 1220 children with ischemic stroke, 219 (18%) developed post-stroke epilepsy compared to 91 comparators (0.7%). The epilepsy risk was highest in the six months following stroke (HR, 119.4 [95% CI, 48.0–297.4]) and remained elevated even at 20 years post-stroke (HR, 7.9 [95% CI, 3.3–19.0]). The cumulative incidence of post-stroke epilepsy increased with longer follow-up periods: 11.9% at 5 years (95% CI, 10.1%–14.0%), 21.6% (95% CI, 19.0%–24.6%), and 26.4% at 30 years (95% CI, 23.0%–30.1%).