BackgroundInitial studies investigating correlations between stroke etiology and clot composition are conflicting and do not account for clot size as determined by area. Radiological studies have shown that cardioembolic strokes are associated with shorter clot lengths and lower clot burden than non-cardioembolic clots.ObjectiveTo report the relationship between stroke etiology, extracted clot area, and histological composition at each procedural pass.MethodsAs part of the multi-institutional RESTORE Registry, the Martius Scarlett Blue stained histological composition and extracted clot area of 612 per-pass clots retrieved from 441 patients during mechanical thrombectomy procedures were quantified. Correlations with clinical and procedural details were investigated.ResultsClot composition varied significantly with procedural passes; clots retrieved in earlier passes had higher red blood cell content (H4=11.644, p=0.020) and larger extracted clot area (H4=10.730, p=0.030). Later passes were associated with significantly higher fibrin (H4=12.935, p=0.012) and platelets/other (H4=15.977, p=0.003) content and smaller extracted clot area. Large artery atherosclerotic (LAA) clots were significantly larger in the extracted clot area and more red blood cell-rich than other etiologies in passes 1–3. Cardioembolic and cryptogenic clots had similar histological composition and extracted clot area across all procedural passes.ConclusionLAA clots are larger and associated with a large red blood cell-rich extracted clot area, suggesting soft thrombus material. Cardioembolic clots are smaller in the extracted clot area, consistent in composition and area across passes, and have higher fibrin and platelets/other content than LAA clots, making them stiffer clots. The per-pass histological composition and extracted clot area of cryptogenic clots are similar to those of cardioembolic clots, suggesting similar formation mechanisms.

Background and Purpose: Timely reperfusion is an important goal in treatment of eligible patients with acute ischemic stroke. However, during the coronavirus disease 2019 (COVID-19) pandemic, prehospital and in-hospital emergency procedures faced unprecedented challenges, which might have caused a decline in the number of acute reperfusion therapy applied and led to a worsening of key quality measures for this treatment during lockdown. Methods: This prospective multicenter cohort study used data from the TRISP (Thrombolysis in Ischemic Stroke Patients) registry of patients with acute ischemic stroke treated with reperfusion therapies, that is, intravenous thrombolysis or endovascular therapy. We compared prehospital and in-hospital time-based performance measures (stroke-onset-to-admission, admission-to-treatment, admission-to-image, and image-to-treatment time) during the first 6 weeks after announcement of lockdown (lockdown period) with the same period in 2019 (reference period). Secondary outcomes included stroke severity (National Institutes of Health Stroke Scale) after 24 hours and occurrence of symptomatic intracranial hemorrhage (following the ECASS [European-Australasian Acute Stroke Study]-II criteria). Results: Across 20 stroke centers, 540 patients were treated with intravenous thrombolysis/endovascular therapy during lockdown period compared with 578 patients during reference period (−7% [95% CI, 5%–9%]). Performance measures did not change significantly during the lockdown period (2020/2019 minutes median: onset-to-admission 133/145; admission-to-treatment 51/48). Same was true for admission-to-image (20/19) and image-to-treatment (31/30) time in patients with available time of first image (n=871, 77.9%). Median National Institutes of Health Stroke Scale on admission (2020/2019: 11/11) and after 24 hours (2020/2019: 6/5) and percentage of symptomatic intracranial hemorrhage (2020/2019: 6.2/5.7) did not differ significantly between both periods. Conclusions: The COVID-19 pandemic lockdown resulted in a mild decline in the number of patients with stroke treated with acute reperfusion therapies. More importantly, the solid stability of key quality performance measures between the 2020 and 2019 period may indicate resilience of acute stroke care service during the lockdown, at least in well-established European stroke centers.

We confirm a rather low public awareness of stroke in Sweden, poorer among males and those with low education. With increasing age, a lower proportion indicated intent to call 112 for stroke symptoms.

Objectives Evidence of endovascular treatment (EVT) for acute large vessel occlusion (LVO) ischemic stroke in patients harboring substantial prestroke disability is lacking due to their exclusion from randomized trials. Here, we used routine care observational data to compare outcomes in patients with and without prestroke disability receiving EVT for LVO ischemic stroke. Methods Consecutive patients undergoing EVT for acute LVO ischemic stroke at the Sahlgrenska University Hospital from January 1st, 2015 to March 31st, 2018 were registered in the Sahlgrenska Stroke Recanalization Registry. Pre-and poststroke functional levels were assessed by the modified Rankin Scale (mRS). Outcomes were recanalization rate (mTICI = 2b/3), symptomatic intracranial hemorrhage [sICH], complications during hospital stay, and return to prestroke functional level and mortality at 3 months. Results Among 591 patients, 90 had prestroke disability (mRS ≥ 3). The latter group were older, more often female, had more comorbidities and higher NIHSS scores before intervention compared to patients without prestroke disability. Recanalization rates (80.0% vs 85.0%, p = 0.211), sICH (2.2% vs 6.3% p = 0.086) and the proportion of patients returning to prestroke functional level (22.7% vs 14.8% p = 0.062) did not significantly differ between those with and without prestroke disability. Patients with prestroke disability had higher complication rates during hospital stay (55.2% vs 40.1% p < 0.01) and mortality at 3 months (48.9% vs 24.3% p < 0.001). Conclusion One of five with prestroke disability treated with thrombectomy for a LVO ischemic stroke returned to their prestroke functional level. However, compared to patients without prestroke disability, mortality at 3 months was higher.