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CNS Neuroscience & Therapeutics Feb 2024In the field of stroke thrombectomy, ineffective clinical and angiographic reperfusion after successful recanalization has drawn attention. Partial or complete... (Review)
Review
In the field of stroke thrombectomy, ineffective clinical and angiographic reperfusion after successful recanalization has drawn attention. Partial or complete microcirculatory reperfusion failure after the achievement of full patency of a former obstructed large vessel, known as the "no-reflow phenomenon" or "microvascular obstruction," was first reported in the 1960s and was later detected in both experimental models and patients with stroke. The no-reflow phenomenon (NRP) was reported to result from intraluminal occlusions formed by blood components and extraluminal constriction exerted by the surrounding structures of the vessel wall. More recently, an emerging number of clinical studies have estimated the prevalence of the NRP in stroke patients following reperfusion therapy, ranging from 3.3% to 63% depending on its evaluation methods or study population. Studies also demonstrated its detrimental effects on infarction progress and neurological outcomes. In this review, we discuss the research advances, underlying pathogenesis, diagnostic techniques, and management approaches concerning the no-reflow phenomenon in the stroke population to provide a comprehensive understanding of this phenomenon and offer references for future investigations.
Topics: Humans; No-Reflow Phenomenon; Microcirculation; Stroke; Thrombectomy; Reperfusion; Treatment Outcome
PubMed: 38358074
DOI: 10.1111/cns.14631 -
Stroke Jan 2021Reperfusion therapy with intravenous thrombolysis or mechanical thrombectomy is effective in improving outcome for ischemic stroke but remains underused. Patients... (Review)
Review
Reperfusion therapy with intravenous thrombolysis or mechanical thrombectomy is effective in improving outcome for ischemic stroke but remains underused. Patients presenting with stroke of unknown onset are a common clinical scenario and a common reason for not offering reperfusion therapy. Recent studies have demonstrated the efficacy of reperfusion therapy in stroke of unknown time of onset, when guided by advanced brain imaging. However, translation into clinical practice is challenged by variability in the available data. Comparison between studies is difficult because of use of different imaging modalities (magnetic resonance imaging or computed tomography), different imaging paradigms (imaging biomarkers of lesion age versus imaging biomarkers of tissue viability), and different populations studied (ie, both patients with large vessel occlusion or those with less severe strokes). Physicians involved in acute stroke care are faced with the key question of which imaging approach they should use to guide reperfusion treatment for stroke with unknown time of onset. In this review, we provide an overview of the available evidence for selecting and treating patients with strokes of unknown onset, based on the underlying imaging concepts. The perspective provided is from the viewpoint of the clinician seeing these patients acutely, to provide pragmatic recommendations for clinical practice.
Topics: Biomarkers; Humans; Neuroimaging; Reperfusion; Stroke; Thrombolytic Therapy; Time-to-Treatment; Treatment Outcome
PubMed: 33302796
DOI: 10.1161/STROKEAHA.120.032020 -
Revue Neurologique Nov 2017The ischemic penumbra is a transient and potentially reversible condition. Therefore, infarct progression and its counterpart penumbral salvage are highly variable and... (Review)
Review
The ischemic penumbra is a transient and potentially reversible condition. Therefore, infarct progression and its counterpart penumbral salvage are highly variable and result from the interaction of 3 major factors: collateral flow, revascularization delay and success. Multimodal brain imaging now offers in clinical practice an exhaustive characterization of the acute ischemic injury: vessel site occlusion, infarction/critical hypoperfusion volume, and collateral flow. From 1995 to 2015, IV alteplase administered within 4.5hours after the onset of acute BI diagnosed by the absence of hemorrhage on a non-contrast head CT scan has been the only approved revascularization treatment. Over the past 2years, 6 randomized trials have confirmed the benefit of a thrombectomy performed within 6-8 hours after the onset of an acute anterior BI downstream of an ICA/M1 occlusion. The recommended imaging modality for such patients remains a NCCT to exclude an hemorrhage and a CTA to confirm the proximal vessel occlusion. As a consequence, in the absence of collateral or penumbral imaging, studies and meta-analyses, have emphasized the importance of treatment delay on the outcome of patient after a revascularisation treatment (tPA/thrombectomy). These findings have supported the development of mobile stroke unit for tPA administration and the direct transfer of the patients eligible to thrombectomy to a comprehensive stroke center, bypassing primary stroke unit and sometimes conventional neuro imaging. In addition randomized controlled trial that did enroll patients based on the presence of a target mismatch on multimodal imaging demonstrated a higher benefit of revascularisation treatment by comparison with those who did not.This year the results of the randomized trial, Diffusion-weighted Imaging or Computerized Tomography Perfusion Assessment with Clinical Mismatch in the Triage of Wake-up and Late Presenting Strokes Undergoing Neurointervention with Trevo (DAWN)demonstrated for the first time that revascularization treatment for BI complicating an ICA or a proximal MCA M1 was still beneficial from 6 to 24hours after onset among patient who did have per their clinical exam and the multimodal brain imaging have a persistent penumbra. With this as a background we will discuss the yield of imaging for the selection of patients for a revascularization therapy.
Topics: Brain Ischemia; Fibrinolytic Agents; Humans; Image Processing, Computer-Assisted; Neuroimaging; Reperfusion; Stroke; Tissue Plasminogen Activator
PubMed: 29037436
DOI: 10.1016/j.neurol.2017.09.002 -
Acta Neurologica Scandinavica Feb 2021Clinical outcomes of acute ischaemic stroke patients have significantly improved with the advent of reperfusion therapy. However, time continues to be a critical factor.... (Review)
Review
Clinical outcomes of acute ischaemic stroke patients have significantly improved with the advent of reperfusion therapy. However, time continues to be a critical factor. Reducing treatment delays by improving workflows can improve the efficacy of acute reperfusion therapy. Systems-based approaches have improved in-hospital temporal parameters, maximizing the utility of reperfusion therapies and improving clinical benefit to patients. However, studies aimed at optimizing and hence reducing treatment delays in emergency department (ED) settings are limited. The aim of this article is to discuss existing systems-based approaches to optimize ED acute stroke workflows and its value in reducing treatment delays and identify gaps in existing workflows that need optimization. Identifying gaps in acute stroke workflow, variations in processes and challenges in implementation, in the in-hospital settings, is essential for systems-based interventions to be effective in delivering improved outcomes for patients with acute ischaemic stroke.
Topics: Brain Ischemia; Emergency Service, Hospital; Humans; Quality of Health Care; Reperfusion; Stroke; Workflow
PubMed: 32882056
DOI: 10.1111/ane.13343 -
Current Neurology and Neuroscience... Jul 2019Urgent reperfusion treatment with intravenous thrombolysis or mechanical thrombectomy reduces disability after ischaemic stroke. Imaging plays an important role in... (Review)
Review
PURPOSE OF REVIEW
Urgent reperfusion treatment with intravenous thrombolysis or mechanical thrombectomy reduces disability after ischaemic stroke. Imaging plays an important role in identifying patients who benefit, particularly in extended time windows. However, the role of post-treatment neuroimaging is less well established. We review recent advances in neuroimaging after reperfusion treatment and provide a practical guide to the options and management implications.
RECENT FINDINGS
Post-treatment imaging is critical to identify patients with reperfusion-related haemorrhage and oedema requiring intervention. It also can guide the timing and intensity of antithrombotic medication. The degree of reperfusion on post-thrombectomy angiography and infarct volume and topography using CT or MRI carry important prognostic significance. Perfusion-weighted MRI and permeability analysis may help detect persistent perfusion abnormalities post-treatment and predict haemorrhagic complications. Post-treatment neuroimaging provides clinically relevant information to identify complications, assess prognosis and perform quality assurance after acute ischaemic stroke. Recent advances in neuroimaging represent a potential avenue to explore post-reperfusion pathophysiology and uncover therapeutic targets for secondary ischaemic and haemorrhagic injury.
Topics: Brain; Brain Ischemia; Humans; Magnetic Resonance Imaging; Neuroimaging; Perfusion; Reperfusion; Stroke; Thrombectomy; Thrombolytic Therapy; Treatment Outcome
PubMed: 31278596
DOI: 10.1007/s11910-019-0970-7 -
JAMA Mar 2024
Topics: Humans; Reperfusion; Stroke; Glucocorticoids
PubMed: 38329442
DOI: 10.1001/jama.2024.0526 -
BMC Neurology Jan 2018Following the success of recent endovascular trials, endovascular therapy has emerged as an exciting addition to the arsenal of clinical management of patients with... (Review)
Review
Following the success of recent endovascular trials, endovascular therapy has emerged as an exciting addition to the arsenal of clinical management of patients with acute ischemic stroke (AIS). In this paper, we present an extensive overview of intravenous and endovascular reperfusion strategies, recent advances in AIS neurointervention, limitations of various treatment paradigms, and provide insights on imaging-guided reperfusion therapies. A roadmap for imaging guided reperfusion treatment workflow in AIS is also proposed. Both systemic thrombolysis and endovascular treatment have been incorporated into the standard of care in stroke therapy. Further research on advanced imaging-based approaches to select appropriate patients, may widen the time-window for patient selection and would contribute immensely to early thrombolytic strategies, better recanalization rates, and improved clinical outcomes.
Topics: Brain Ischemia; Endovascular Procedures; Fibrinolytic Agents; Humans; Patient Selection; Reperfusion; Stroke; Thrombolytic Therapy; Treatment Outcome
PubMed: 29338750
DOI: 10.1186/s12883-017-1007-y -
Journal of Cerebral Blood Flow and... May 2021While the time window for reperfusion after ischemic stroke continues to increase, many patients are not candidates for reperfusion under current guidelines that allow... (Comparative Study)
Comparative Study Review
While the time window for reperfusion after ischemic stroke continues to increase, many patients are not candidates for reperfusion under current guidelines that allow for reperfusion within 24 h after last known well time; however, many case studies report favorable outcomes beyond 24 h after symptom onset for both spontaneous and medically induced recanalization. Furthermore, modern imaging allows for identification of penumbra at extended time points, and reperfusion risk factors and complications are becoming better understood. Taken together, continued urgency exists to better understand the pathophysiologic mechanisms and ideal setting of delayed recanalization beyond 24 h after onset of ischemia.
Topics: Brain; Cerebral Blood Volume; Cerebrovascular Circulation; Child; Combined Modality Therapy; Diffusion Magnetic Resonance Imaging; Female; Fibrinolytic Agents; Humans; Ischemic Stroke; Magnetic Resonance Angiography; Male; Mechanical Thrombolysis; Middle Aged; Reperfusion; Risk Factors; Thrombolytic Therapy; Time Factors; Time-to-Treatment; Tissue Plasminogen Activator; Tomography, X-Ray Computed; Treatment Outcome
PubMed: 33325765
DOI: 10.1177/0271678X20978861 -
Transplantation Proceedings Oct 2020Orthotopic liver transplantation (LT) is a technically complex surgical procedure associated with a major risk of hemodynamic instability and metabolic derangement,... (Observational Study)
Observational Study
BACKGROUND
Orthotopic liver transplantation (LT) is a technically complex surgical procedure associated with a major risk of hemodynamic instability and metabolic derangement, especially in patients with coexisting renal dysfunction. Some centers have applied intraoperative renal replacement therapy (ioRRT) to support patients with preoperative renal failure and prevent critical complications. Although there is a strong theoretical rationale for this treatment, there remains a paucity of definite data demonstrating its benefits.
METHODS
This was a retrospective observational study of all adult patients undergoing intraoperative dialysis in our center from January 2010 till December 2016.
RESULTS
The study group consisted of 88 patients with a mean MELD score of 31.4. Six patients underwent simultaneous liver and kidney transplantation. Forty-four (50%) recipients were admitted to the intensive care unit before transplantation, and 19 (21.6%) needed mechanical ventilation. Twenty-eight (31.8%) of the procedures were retransplantations, and 40 (45.4%) patients had been undergoing renal replacement therapy before LT. The mean preoperative serum creatinine was 2.82 ± 1.13 mg/dL. The majority of patients (54.5%) was operated on using the veno-venous bypass technique. The mean arterial blood pH and potassium levels after reperfusion were 7.2 ± 0.12 and 4.04 ± 0.95 mmol/L, respectively. Postreperfusion syndrome (PRS) occurred in 11 (13.9%) patients in whom dialysis started at least 15 minutes before reperfusion. Dialysis circuit clotting occurred in 9.1% of cases. There were no other adverse events of ioRRT.
CONCLUSION
Our data suggests that intraoperative dialysis in severely ill patients with a high MELD score is safe and effective. Lower than expected PRS occurrence needs to be confirmed in a study with a control group.
Topics: Adult; Female; Humans; Kidney Transplantation; Liver Transplantation; Male; Middle Aged; Renal Dialysis; Reperfusion; Reperfusion Injury; Retrospective Studies
PubMed: 32448654
DOI: 10.1016/j.transproceed.2020.01.129 -
European Journal of Neurology Jul 2022Reperfusion therapy is the mainstay of treatment for acute ischaemic stroke (AIS); however, little is known about the use of reperfusion therapy and time delay amongst...
BACKGROUND AND PURPOSE
Reperfusion therapy is the mainstay of treatment for acute ischaemic stroke (AIS); however, little is known about the use of reperfusion therapy and time delay amongst immigrants.
METHODS
This is a Danish nationwide register-based cohort study of patients with AIS aged ≥18 years (n = 49,817) recruited from 2009 to 2018. Use of reperfusion therapy (intravenous thrombolysis and/or mechanical thrombectomy) and time delay between immigrants and Danish-born residents were compared using multivariable logistics and quantile regression.
RESULTS
Overall, 10,649 (39.8%) Danish-born residents and 452 (39.0%) immigrants with AIS were treated with reperfusion therapy in patients arriving <4.5 h following stroke onset. Compared with Danish-born residents, immigrants had lower odds of receiving reperfusion therapy after adjustment for prehospital delay, age, sex, stroke severity, sociodemographic factors and comorbidities (adjusted odds ratio 0.67; 95% confidence interval 0.49-0.92, p = 0.01). The lowest odds were observed amongst immigrants originating from Poland and non-Western countries. Similarly, immigrants had a longer prehospital delay than Danish-born residents in the fully adjusted model in patients arriving <4.5 h after stroke onset (15 min; 95% confidence interval 4-26 min, p = 0.03). No evidence was found that system delay and clinical outcome differed between immigrants and Danish-born residents in patients eligible for reperfusion therapy after adjustment for sociodemographic factors and comorbidities.
CONCLUSION
Immigration status was significantly associated with lower chances of receiving reperfusion therapy and there may be differences in patient delay between immigrants and Danish-born residents in patients arriving to a stroke unit <4.5 h after stroke onset.
Topics: Adolescent; Adult; Brain Ischemia; Cohort Studies; Denmark; Emigration and Immigration; Humans; Ischemic Stroke; Reperfusion; Stroke; Treatment Outcome
PubMed: 35212085
DOI: 10.1111/ene.15303