50 research outputs found
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Rectifying the Misconceptions about Current Best Management of Asymptomatic Carotid Stenosis is Not about Revising History
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Additional Opportunity to Rectify Misconceptions Regarding Current Best Management of Asymptomatic Carotid Stenosis
No full textOptimizing the Definitions of Stroke, Transient Ischemic Attack, and Infarction for Research and Application in Clinical Practice
No full textBackground and purposeUntil now, stroke and transient ischemic attack (TIA) have been clinically based terms which describe the presence and duration of characteristic neurological deficits attributable to intrinsic disorders of particular arteries supplying the brain, retina, or (sometimes) the spinal cord. Further, infarction has been pathologically defined as death of neural tissue due to reduced blood supply. Recently, it has been proposed we shift to definitions of stroke and TIA determined by neuroimaging results alone and that neuroimaging findings be equated with infarction.MethodsWe examined the scientific validity and clinical implications of these proposals using the existing published literature and our own experience in research and clinical practice.ResultsWe found that the proposals to change to imaging-dominant definitions, as published, are ambiguous and inconsistent. Therefore, they cannot provide the standardization required in research or its application in clinical practice. Further, we found that the proposals are scientifically incorrect because neuroimaging findings do not always correlate with the clinical status or the presence of infarction. In addition, we found that attempts to use the proposals are disrupting research, are otherwise clinically unhelpful and do not solve the problems they were proposed to solve.ConclusionWe advise that the proposals must not be accepted. In particular, we explain why the clinical focus of the definitions of stroke and TIA should be retained with continued sub-classification of these syndromes depending neuroimaging results (with or without other information) and that infarction should remain a pathological term. We outline ways the established clinically based definitions of stroke and TIA, and use of them, may be improved to encourage better patient outcomes in the modern era
Misconceptions regarding the adequacy of best medical intervention alone for asymptomatic carotid stenosis
No full textBACKGROUND: Medical intervention (risk factor identification, lifestyle coaching, and medication) for stroke prevention has improved significantly. It is likely that no more than 5.5% of persons with advanced asymptomatic carotid stenosis (ACS) will now benefit from a carotid procedure during their lifetime. However, some question the adequacy of medical intervention alone for such persons and propose using markers of high stroke risk to intervene with carotid endarterectomy (CEA) and/or carotid angioplasty/stenting (CAS). Our aim was to examine the scientific validity and implications of this proposal. METHODS: We reviewed the evidence for using medical intervention alone or with additional CEA or CAS in persons with ACS. We also reviewed the evidence regarding the validity of using commonly cited makers of high stroke risk to select such persons for CEA or CAS, including markers proposed by the European Society for Vascular Surgery in 2017. RESULTS: Randomized trials of medical intervention alone versus additional CEA showed a definite statistically significant CEA stroke prevention benefit only for selected average surgical risk men aged less than 75 to 80 years with 60% or greater stenosis using the North American Symptomatic Carotid Endarterectomy Trial criteria. However, the most recent measurements of stroke rate with medical intervention alone are overall lower than for those who had CEA in these randomized trials. Randomized trials of CEA versus CAS in persons with ACS were underpowered. However, the trend was for higher stroke and death rates with CAS. There are no randomized trial results related to comparing current optimal medical intervention with CEA or CAS. Commonly cited markers of high stroke risk in relation to ACS lack specificity, have not been assessed in conjunction with current optimal medical intervention, and have not been shown in randomized trials to identify those who benefit from a carotid procedure in addition to current optimal medical intervention. CONCLUSIONS: Medical intervention has an established role in the current routine management of persons with ACS. Stroke risk stratification studies using current optimal medical intervention alone are the highest research priority for identifying persons likely to benefit from adding a carotid procedure
Reliability of Hand-Held Transcranial Doppler with M-mode Ultrasound in Middle Cerebral Artery Measurement
No full textPurpose: To determine the intra- and interrater agreement of mean flow velocity (MFV) and pulsatility index (PI) measurement in middle cerebral arteries, assessed by transcranial Doppler (TCD) with M-mode.
Methods: Masked experienced neurosonologists performed TCD with M-mode using handheld probe in healthy adult volunteers. The Bland–Altman method for concordance and intraclass correlation coefficient were used.
Results: Seventy-seven healthy volunteers and seven raters participated (3 on regular TCD shift and 4 off-shift). The intrarater absolute mean difference between measurements was 5.5 cm/s [95% confidence interval (CI), 4.7–6.3] for MVF and 0.073 (95% CI, 0.063–0.083) for PI. The difference between MFV measurements was significantly higher in off-shift raters (p=0.015). The interrater absolute mean difference between measurements was 6.5 cm/s (95% CI, 5.5–7.5) for MVF and 0.065 (95% CI, 0.059–0.071) for PI. No influence was found for the middle cerebral artery side, volunteer's sex, or age, and there was no significant difference between raters. The intraclass correlation coefficient was 82.2% (95% CI 77.8–85.6) and 72.9% (95% CI 67.4–77.6) for MFV and PI, respectively.
Conclusions: There exists good intra- and interrater agreement in MFV and PI measurements using M-mode TCD. These results support the use of this noninvasive tool and are important for clinical and investigational purposes
The Role of TCD in the Evaluation of Acute Stroke
No full textBACKGROUND: The additional information that transcranial Doppler (TCD) can provide as part of a multimodal imaging stroke protocol in the setting of hyper acute strokes has not been evaluated.
METHODS: Consecutive patients admitted between December 2012 and January 2015 with ischemic stroke of less than 4.5 hours of onset were studied as soon as possible with a protocol consisting of noncontrast brain computed tomography, computed tomography angiography of supra-aortic vessels, diffusion-weighted magnetic resonance imaging, and TCD.
RESULTS: Eighty-six patients were included. The imaging protocol was performed 113.9 (+/- 23) minutes after the stroke symptoms appeared and by TCD after 150.2 (+/- 19) minutes. Sixty-six (76.7%) patients were treated with revascularization therapies. TCD provided additional information in 49 cases (56.9.4%, 95 CI 46.4-66.9). More than one piece of additional information was obtained in 17 patients. The most frequent additional information was collateral pathways, information related to patency of vessels, and active microembolization. Multivariate analysis demonstrated that, intracranial vessel occlusion (P < .001) and optimal sonographic windows (P <. 004) were the variables associated with additional information. In 15 patients (17.4%; 95 CI 9.4-25.5) the additional information changed the management. In 8 patients endovascular rescue was applied after the failure of intravenous thrombolysis; in 5 patients angiography was suspended and in 2 other cases aggressive neurocritical care was indicated.
CONCLUSIONS: TCD in the first 4.5 hours of acute ischemia can provide additional information to a multimodal acute ischemic stroke imaging protocol, and can induce changes in the management of a proportion of these patients
Emergency Department Workflow Times of Intravenous Thrombolysis with Tenecteplase versus Alteplase in Acute Ischemic Stroke: A Prospective Cohort Study before and during the COVID-19 Pandemic
No full textIntroduction: Tenecteplase (TNK) has demonstrated to be non-inferior to alteplase (ALT) for intravenous thrombolysis (IVT) in acute ischemic stroke (AIS). There are potential workflow benefits associated with TNK use, aiming to reduce patient length of stay in the emergency department. Our aim was to investigate whether the routine use of TNK during the COVID-19 pandemic influenced workflow times compared to historical use of ALT, while maintaining non-inferior clinical outcomes in a non-drip and ship scenario of a comprehensive stroke center. Methods: We included patients with AIS admitted from September 2019 to September 2022 and compared those treated with TNK during the COVID-19 pandemic to those treated with ALT in the period immediately before. We compared emergency department length of stay (EDLOS), door-to-needle time (DTN), door-to-groin puncture time (DTG), clinical and safety outcomes with adjusted general linear regression models. Results: 110 patients treated with TNK and 111 with ALT were included in this study. Mean EDLOS was 251 (SD = 164) min for TNK users versus 240 (SD = 148) min for ALT (p = 0.62). Mean DTN was 43 (SD = 25) min for TNK versus 46 (SD = 27) min for ALT users (p = 0.39). Mean DTN under 60 min was achieved in 86 (78.2%) patients and in 85 (76.5%) patients of the TNK and ALT groups, respectively (p = 1.0). DTN under 45 min was achieved in 65.4% and 58.6% (p = 0.65) of the TNK and ALT groups, respectively. DTG time was 114 (SD = 43) min for TNK versus 111 (58 = SD) min in the ALT group (p = 0.88). DTG under 90 min was achieved in 32% of the TNK group and 35% of the ALT group (p = 0.69). There were no differences in any of the clinical or safety outcomes between groups at 90 days. Conclusions: The adoption of TNK during COVID-19 pandemic did not result in a change in EDLOS, DTN, or DTG times when compared to ALT in this cohort. Safety and clinical outcomes were similar between groups. Probably a greater benefit could have been seen in a drip and ship thrombolysis setting. Further research is needed to assess the potential advantages of TNK in drip and ship scenarios of IVT
Exclusion Criteria for Intravenous Thrombolysis in Stroke Mimics: An Observational Study
No full textBackground: Stroke mimics (SMs) are frequent in emergency departments (EDs), but are treated infrequently with intravenous recombinant tissue plasminogen activator (rt-PA) thrombolysis. We aimed at identifying the factors that lead to the exclusion of SMs from thrombolytic therapy.Methods: Consecutive patients presenting to the ED between December 2004 and March 2011 with symptoms that suggested acute ischemic stroke were included.Results: Eight hundred forty-two patients were included in this study; 113 (13.4%) were considered SMs; these patients were younger (P = .01), more frequently diabetic (P = .001), arrived later to the ED (P = .03), had lower National Institutes of Health Stroke Scale scores (P 1 contraindication. The most frequent of these were being beyond the therapeutic window for thrombolysis (n = 96) and having deficits not measurable by the National Institutes of Health Stroke Scale or very mild symptoms before the start of rt-PA (n = 37). Twenty-four (21.2%) patients had both contraindications simultaneously. Two patients (1.76%) in the SM group were candidates for rt-PA but did not receive this treatment because they or their family rejected it. Of 729 stroke patients, 87 (11.9%) did receive rt-PA.Conclusions: SM patients frequently had exclusion criteria for systemic thrombolysis, the most frequent being presenting beyond the established thrombolytic windo
Intravenous Thrombolysis in Patients 90 years or Older with Moderate to Severe Acute Ischemic Stroke Increases Ambulation at Discharge and is Safe: A prospective cohort study from a single center in Santiago, Chile.
No full textIntroduction: The World Health Organization predicts that the global population aged 60 years and older will double by 2050, leading to a significant rise in the public health impact of acute ischemic stroke (AIS). Existing stroke guidelines do not specify an upper age limit for the administration of intravenous thrombolysis (IVT), although some suggest a relative exclusion criterion in patients aged ≥ 80 in the 3 – 4.5 hour window. Many physicians avoid treating these patients with IVT, argumenting high risk and little benefit.
Our aim was to investigate the efficacy and safety of IVT treatment in patients with non-minor AIS aged ≥ 90, admitted to our institution. The primary efficacy endpoint was the ability to walk at discharge (mRS 0-3) and the primary safety endpoints were death and symptomatic intracerebral hemorrhagic transformation (sIHT) at discharge.
Methods: Patients with AIS aged ≥ 90 admitted to our center from January 2003 to December 2022 were included. They were selected if had an NIHSS ≥ 5, were previously ambulatory (prestroke mRS score 3 or less) and arrived within 6 hours from symptom onset. Those treated or not with IVT were compared with univariate analysis.
Results: The mean age was 93.2 (2.4) years and 51 (73.9%) were female. The admission mRS and NIHSS were 1 (IQR 0 – 2) and 14 (IQR 7 – 22), respectively. Thrombolysed patients had a shorter time from symptom onset to door and lower glycemia on admission. IVT was associated with a higher proportion of patients achieving mRS 0 – 3 at discharge (p=0.03) and at 90 days (p=0.04). There were no differences between groups in the risk of death (p=0.55) or sIHT (p=0.38).
Conclusion: In this small sample, ambulatory patients aged ≥ 90 with moderate or severe AIS treated with IVT, had increased odds of being able to walk independently at discharge than those not treated, without safety concerns
Validation of the transcranial Doppler rescue criteria for mechanical thrombectomy
No full textReperfusion; Stroke; ThrombectomyReperfusión; Ictus; TrombectomíaReperfusió; Ictus; TrombectomiaBackground and Purpose
Transcranial Doppler (TCD) identifies acute stroke patients with arterial occlusion where treatment may not effectively open the blocked vessel. This study aimed to examine the clinical utility and prognostic value of TCD flow findings in patients enrolled in a multicenter prospective study (CLOTBUST-PRO).
Methods
Patients enrolled with intracranial occlusion on computed tomography angiography (CTA) who underwent urgent TCD evaluation before intravenous thrombolysis was included in this analysis. TCD findings were assessed using the mean flow velocity (MFV) ratio, comparing the reciprocal ratios of the middle cerebral artery (MCA) depths bilaterally (affected MCA-to-contralateral MCA MFV [aMCA/cMCA MFV ratio]).
Results
A total of 222 patients with intracranial occlusion on CTA were included in the study (mean age: 64 ± 14 years, 62% men). Eighty-eight patients had M1 MCA occlusions; baseline mean National Institutes of Health Stroke Scale (NIHSS) score was 16, and a 24-hour mean NIHSS score was 10 points. An aMCA/cMCA MFV ratio of <.6 had a sensitivity of 99%, specificity of 16%, positive predictive value (PV) of 60%, and negative PV of 94% for identifying large vessel occlusion (LVO) including M1 MCA, terminal internal carotid artery, or tandem ICA/MCA. Thrombolysis in Brain Ischemia scale, with (grade ≥1) compared to without flow (grade 0), showed a sensitivity of 17.1%, specificity of 86.9%, positive PV of 62%, and negative PV of 46% for identifying LVO.
Conclusions
TCD is a valuable modality for evaluating arterial circulation in acute ischemic stroke patients, demonstrating significant potential as a screening tool for intravenous/intra-arterial lysis protocols
