Cerebrovascular diseases
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Cerebrovascular diseases · Jan 2011
Review Historical ArticleThe ischemic penumbra: correlates in imaging and implications for treatment of ischemic stroke. The Johann Jacob Wepfer award 2011.
The concept of the ischemic penumbra was formulated 30 years ago based on experiments in animal models showing functional impairment and electrophysiological disturbances with decreasing flow to the brain below defined values (the threshold for function) and irreversible tissue damage with the blood supply further decreased (the threshold for infarction). The perfusion range between these thresholds was termed 'penumbra', and restitution of flow above the functional threshold was able to reverse the deficits without permanent damage. However, in further experiments, the dependency of the development of irreversible lesions on the interaction of the severity and duration of critically reduced blood flow was established - proving that the lower the flow, the shorter the time for efficient reperfusion. ⋯ Some of these discrepancies can be explained by unselective application of relative perfusion thresholds, which might be improved by more complex analytical procedures. Heterogeneity of the MRI signatures used for the definition of the mismatch are also responsible for disappointing results in the application of PW/DW-MRI for the selection of patients for clinical trials. As long as a validation of the mismatch selection paradigm is lacking, its use as a surrogate marker of outcome is limited.
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Cerebrovascular diseases · Jan 2011
Comparative StudyConcerns for the reliability and validity of the National Stroke Project Stroke Severity Scale.
The National Stroke Project (NSP) was a retrospective cohort study of US Medicare beneficiaries hospitalized with stroke or transient ischemic attack (TIA). The NSP included a simple assessment of stroke severity (NSP-Stroke Scale, NSP-SS). Used for risk adjustment in outcome studies, the reliability and validity of the NSP-SS have not been assessed. We determined the reliability, concurrent and construct validity of the NSP-SS. ⋯ The NSP-SS has moderate-substantial reliability but poor content validity and poor to moderate concurrent validity as compared with the NIH-SS. In addition, it is not clear that the NSP-SS is easier to extract from medical records than the NIH-SS. Given this, and its other limitations, the utility of this scale for risk adjustment in future stroke outcome studies is questionable.
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Cerebrovascular diseases · Jan 2011
Randomized Controlled TrialFrequent early cardiac complications contribute to worse stroke outcome in atrial fibrillation.
Atrial fibrillation (AF) is associated with worse outcomes following ischemic stroke and more frequent cardiac complications in the general population. We aimed to establish whether early cardiac complications contribute to the poorer ischemic stroke outcomes in patients with AF, independent of baseline differences in age, stroke severity and cardiovascular risk factors. This might have important implications for acute stroke management in patients with AF. ⋯ Early SCAE are common after stroke and are independently associated with the presence of AF. Given that many cardiac complications are potentially remediable, these results highlight the need for more rigorous surveillance for cardiac complications in acute ischemic stroke patients with AF.
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Cerebrovascular diseases · Jan 2011
Endovascular reconstruction with the Willis covered stent for the treatment of large or giant intracranial aneurysms.
The purpose of this study was to evaluate the feasibility, safety and efficacy of endovascular treatment of large or giant intracranial aneurysms with the Willis covered stent. ⋯ Endovascular treatment of large or giant intracranial aneurysm with the Willis covered stent is feasible, safe and efficacious in selected cases. Endoleak is a frequent issue after initial covered stent placement, but can be eliminated or dramatically reduced to minimal endoleak by additional covered stent placement and/or balloon reinflation. Minor endoleak is likely to spontaneously resolve over time.