Recent Vitamin K Antagonist Use and Intracranial Hemorrhage After Endovascular Thrombectomy for Acute Ischemic Stroke.

Importance: Use of oral vitamin K antagonists (VKAs) may place patients undergoing endovascular thrombectomy (EVT) for acute ischemic stroke caused by large vessel occlusion at increased risk of complications. Objective: To determine the association between recent use of a VKA and outcomes among patients selected to undergo EVT in clinical practice. Design, Setting, and Participants: Retrospective, observational cohort study based on the American Heart Association's Get With the Guidelines-Stroke Program between October 2015 and March 2020. From 594 participating hospitals in the US, 32 715 patients with acute ischemic stroke selected to undergo EVT within 6 hours of time last known to be well were included. Exposure: VKA use within the 7 days prior to hospital arrival. Main Outcome and Measures: The primary end point was symptomatic intracranial hemorrhage (sICH). Secondary end points included life-threatening systemic hemorrhage, another serious complication, any complications of reperfusion therapy, in-hospital mortality, and in-hospital mortality or discharge to hospice. Results: Of 32 715 patients (median age, 72 years; 50.7% female), 3087 (9.4%) had used a VKA (median international normalized ratio [INR], 1.5 [IQR, 1.2-1.9]) and 29 628 had not used a VKA prior to hospital presentation. Overall, prior VKA use was not significantly associated with an increased risk of sICH (211/3087 patients [6.8%] taking a VKA compared with 1904/29 628 patients [6.4%] not taking a VKA; adjusted odds ratio [OR], 1.12 [95% CI, 0.94-1.35]; adjusted risk difference, 0.69% [95% CI, -0.39% to 1.77%]). Among 830 patients taking a VKA with an INR greater than 1.7, sICH risk was significantly higher than in those not taking a VKA (8.3% vs 6.4%; adjusted OR, 1.88 [95% CI, 1.33-2.65]; adjusted risk difference, 4.03% [95% CI, 1.53%-6.53%]), while those with an INR of 1.7 or lower (n = 1585) had no significant difference in the risk of sICH (6.7% vs 6.4%; adjusted OR, 1.24 [95% CI, 0.87-1.76]; adjusted risk difference, 1.13% [95% CI, -0.79% to 3.04%]). Of 5 prespecified secondary end points, none showed a significant difference across VKA-exposed vs VKA-unexposed groups. Conclusions and Relevance: Among patients with acute ischemic stroke selected to receive EVT, VKA use within the preceding 7 days was not associated with a significantly increased risk of sICH overall. However, recent VKA use with a presenting INR greater than 1.7 was associated with a significantly increased risk of sICH compared with no use of anticoagulants.

Endovascular Treatment of Acute Ischemic Stroke With the Penumbra System in Routine Practice: COMPLETE Registry Results.

BACKGROUND AND PURPOSE: The purpose of the COMPLETE (International Acute Ischemic Stroke Registry With the Penumbra System Aspiration Including the 3D Revascularization Device) registry was to evaluate the generalizability of the safety and efficacy of the Penumbra System (Penumbra, Inc, Alameda) in a real-world setting. METHODS: COMPLETE was a global, prospective, postmarket, multicenter registry. Patients with large vessel occlusion-acute ischemic stroke who underwent mechanical thrombectomy using the Penumbra System with or without the 3D Revascularization Device as frontline approach were enrolled at 42 centers (29 United States, 13 Europe) from July 2018 to October 2019. Primary efficacy end points were successful postprocedure angiographic revascularization (modified Thrombolysis in Cerebral Infarction ≥2b) and 90-day functional outcome (modified Rankin Scale score 0-2). The primary safety end point was 90-day all-cause mortality. An imaging core lab determined modified Thrombolysis in Cerebral Infarction scores, Alberta Stroke Program Early CT Scores, clot location, and occurrence of intracranial hemorrhage at 24 hours. Independent medical reviewers adjudicated safety end points. RESULTS: Six hundred fifty patients were enrolled (median age 70 years, 54.0% female, 49.2% given intravenous recombinant tissue-type plasminogen activator before thrombectomy). Rate of modified Thrombolysis in Cerebral Infarction 2b to 3 postprocedure was 87.8% (95% CI, 85.3%-90.4%). First pass and postprocedure rates of modified Thrombolysis in Cerebral Infarction 2c to 3 were 41.5% and 66.2%, respectively. At 90 days, 55.8% (95% CI, 51.9%-59.7%) had modified Rankin Scale score 0 to 2, and all-cause mortality was 15.5% (95% CI, 12.8%-18.3%). CONCLUSIONS: Using Penumbra System for frontline mechanical thrombectomy treatment of patients with large vessel occlusion-acute ischemic stroke in a real-world setting was associated with angiographic, clinical, and safety outcomes that were comparable to prior randomized clinical trials with stringent site and operator selection criteria. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03464565.

Research on intracranial atherosclerosis from the East and west: why are the results different?

Intracranial atherosclerosis (ICAS) is a major cause of stroke worldwide and is more common in Asians than Caucasians. The study results from the East and West are generally similar, but notable differences exist. For example, studies from the East have reported that ICAS is associated with young age, whereas ICAS seems to be associated with old age in the West. Studies from the East have strongly suggested that mild ICAS associated with branch occlusion is one of the main causes of single subcortical infarction, whereas this aspect has not been considered in stroke classification systems developed in the West. While clopidogrel is commonly used in patients with large artery disease in the West, cilostazol has been more extensively studied and commonly used in ICAS patients in the East. A randomized controlled study from the West reported negative results regarding the efficacy of stenting in ICAS patients due largely to a relatively high rate of periprocedural adverse events, whereas research papers from the East have reported a relatively lower rate of complications. Studies to narrow these East-West gaps should be performed, including risk factor studies using homogenous ethnic populations, studies investigating appropriate classification systems, drug trials in different ethnic populations, and rigorous high standard randomized controlled studies on the efficacy of stenting in Eastern populations.

Prevalence and prognosis of coexistent asymptomatic intracranial stenosis.

BACKGROUND AND PURPOSE: There are limited data on the prevalence and prognosis of asymptomatic intracranial stenosis (AIS). METHODS: Baseline cerebral angiograms and MR angiograms were used to determine AIS (50% to 99%) coexistent to symptomatic intracranial stenosis for patients enrolled in the Warfarin-Aspirin Symptomatic Intracranial Disease study. RESULTS: Coexisting AIS were detected in 18.9% (n=14/74) of patients undergoing 4-vessel cerebral angiography and 27.3% (n=65/238) of patients undergoing MR angiogram. During a mean follow-up period of 1.8 years, no ischemic strokes were attributable to an AIS on cerebral angiography and 5 ischemic strokes (5.9%, 95% CI: 2.1% to 12.3%) occurred in the AIS territory on MR angiogram (risk at 1 year=3.5%, 95% CI: 0.8% to 9.0%). CONCLUSIONS: Whereas the prevalence of coexisting AIS (50% to 99%) in patients with symptomatic stenosis is high, the risk of stroke from these asymptomatic stenoses is low.

Therapeutic hypothermia after cardiac arrest: performance characteristics and safety of surface cooling with or without endovascular cooling.

INTRODUCTION: Various methods are available to induce and maintain therapeutic hypothermia after cardiac arrest, but little data is available comparing device-mediated cooling to simple surface methods in this setting. METHODS: To assess the performance characteristics of simple surface cooling with or without an endovascular cooling catheter system, we retrospectively reviewed all cases of hypothermia for comatose survivors of cardiac arrest treated at a single academically affiliated urban hospital. Forty two comatose survivors of cardiac arrest were treated over a 3.5-year period. Hypothermia was induced and maintained by simple surface methods (ice packs, cooling blankets) with or without placement of an endovascular cooling catheter system with automated temperature feedback regulation. RESULTS: Overall, the rate of active cooling was not different between patients treated with endovascular catheter-assisted hypothermia and patients treated with surface cooling alone. However, use of a larger (14 F) catheter was associated with faster cooling rates. Maintenance of goal temperature (33 degrees C) was far better controlled with the use of a cooling catheter. Use of surface cooling alone was associated with significant temperature overshoot. Patients treated with surface cooling alone spent more time bradycardic. CONCLUSION: Use of an endovascular cooling catheter as part of a treatment protocol for hypothermia after cardiac arrest provides better control during maintenance of hypothermia, preventing temperature overshoot. Active cooling rates may be enhanced by the use of a larger cooling catheter.

Prognostic significance of angiographically confirmed large vessel intracranial occlusion in patients presenting with acute brain ischemia.

INTRODUCTION: Independent predictors of outcome for ischemic stroke include age and initial stroke severity. Intracranial large-vessel occlusion would be expected to predict poor outcome. Because large-vessel occlusion and stroke severity are likely correlated, it is unclear if largevessel occlusion independently predicts outcome or is simply a marker for stroke severity. METHODS: A consecutive series of patients with suspected stroke or transient ischemic attack were imaged acutely with computed tomography angiography (CTA). CTAs were reviewed for intracranial large-vessel occlusion as the cause of the stroke. Baseline National Institutes of Health Stroke Scale (NIHSS) score, discharge modified Rankin score, and patient demographics were abstracted from hospital records. Poor neurological outcome was defined as modified Rankin score exceeding 2. RESULTS: Seventy-two consecutive patients with acute ischemic stroke were imaged with CTA. The median (range) time from stroke symptom onset to CT imaging was 183 minutes (25 minutes to 4 days). Median NIHSS score was 6 (1-32) and intracranial large-vessel occlusion was found in 28 (38.9%) patients. Fifty-six percent of patients had a good neurological outcome. In multivariate logistic regression analysis, two variables predicted poor neurological outcome: baseline NIHSS score (OR 1.21, 95% CI [1.07-1.37]) and presence of intracranial large-vessel occlusion (OR 4.48, 95% CI [1.19-16.9]). The predictive value of large-vessel occlusion on outcome was similar to an 8-point increase in NIHSS score. CONCLUSION: In patients presenting with acute brain ischemia, intracranial large-vessel occlusion independently predicts poor neurological outcome at hospital discharge, as does the presence of a high NIHSS score. Performing routine intracranial vascular imaging on acute stroke patients may allow for more accurate determination of prognosis and may also guide therapy.

Initial Glasgow Coma Scale score predicts outcome following thrombolysis for posterior circulation stroke.

BACKGROUND: Randomized trials of thrombolytic stroke treatment have either excluded patients with posterior circulation ischemia or used inclusion criteria making enrollment of these patients less likely. Consequently, there is less published information on thrombolytic therapy for posterior circulation stroke. OBJECTIVE: To determine effective thrombolytic treatment times for posterior circulation stroke and factors that might help predict clinical outcome. DESIGN: We describe our experience treating 21 consecutive patients with either intravenous or intra-arterial thrombolytic therapy for posterior circulation ischemic stroke between October 9, 1993, and February 19, 2001. MAIN OUTCOME MEASURES: National Institutes of Health Stroke Scale, Glasgow Coma Scale, and modified Rankin Scale scores were evaluated at baseline, and the modified Rankin Scale was measured 3 months after stroke, with a good outcome being a modified Rankin Scale score of 2 or less. RESULTS: Nine patients received intravenous therapy; 12 patients received intra-arterial therapy. The median National Institutes of Health Stroke Scale score at onset was 20 (range, 2-39), and the median Glasgow Coma Scale score was 9 (range, 3-15). Twelve patients were treated within 8 hours of symptom onset (range, 1 1/2 hours to 16 days). Nine patients (43%) had a modified Rankin Scale score of 2 or less at 3 months. The initial Glasgow Coma Scale score and treatment within 8 hours of symptom onset were each associated with good outcome, but the initial National Institutes of Health Stroke Scale score was not predictive. CONCLUSIONS: Thrombolytic therapy for posterior circulation stroke may be beneficial even when initiated 8 hours after symptom onset. Level of consciousness, as measured by Glasgow Coma Scale score, seems to be a more important predictor of outcome than the initial National Institutes of Health Stroke Scale score.

Bow hunter stroke caused by cervical disc herniation. Case report.

Bow hunter stroke, which is characterized by transient vertebrobasilar ischemia brought on by head turning, is an unusual condition usually caused by structural abnormalities at the craniocervical junction. The authors present a case in which compression of the left vertebral artery (VA) at the C4-5 level was caused by a laterally herniated intervertebral disc. A 56-year-old man presented with a 6-month history of dizziness and syncope when he turned his head 45 degrees or more to the left. Transcranial Doppler (TCD) ultrasonography demonstrated decreased blood flow through the left VA, and angiography revealed an occlusion of the left VA at the C4-5 level, both when the patient turned his head to the left. Via an anterior cervical approach, the VA canal was unroofed through the transverse foramina to decompress the left VA at C4-5; intraoperatively, the left VA was found to be compressed by a laterally herniated cervical disc fragment. To the best of the authors' knowledge this is the first report of a laterally herniated cervical disc causing bow hunter stroke. The use of TCD may be of value in the diagnosis and management of the disorder, and herniated cervical disc must be included in the roster of potential causes for this rare disease.