Cerebrovascular diseases
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Cerebrovascular diseases · Jan 2012
The severity of ischemia determines and predicts malignant brain edema in patients with large middle cerebral artery infarction.
In order to determine the impact of the severity of ischemia on malignant edema formation, we investigated various degrees of perfusional deficit by (11)C-flumazenil PET in patients with large middle cerebral artery (MCA) infarction. ⋯ Malignant MCA infarction seems to be determined more by the volume of severe perfusional deficit than that of total perfusional deficit. Assessment of severely ischemic areas allows prediction of malignant edema formation and might help to select candidates for hemicraniectomy.
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Cerebrovascular diseases · Jan 2012
Ambient air pollutants and acute case-fatality of cerebro-cardiovascular events: Takashima Stroke and AMI Registry, Japan (1988-2004).
Apart from the conventional risk factors, cerebro-cardiovascular disease (CVD) are also reported to be associated with air pollution, thus lowering the level of exposure might contribute in prevention activities to reduce the associated adverse outcomes. Though few studies conducted in Japan have reported on the CVD mortality but none have explored the effect of air pollutant exposure on the acute case-fatality of CVD. We investigated the effects of air pollution exposure on acute case-fatality of stroke and acute myocardial infarction (AMI) in a setting where pollutant levels are rather low. ⋯ We observed association between NO(2) levels, an index of traffic related air pollution, with the acute case-fatality of stroke, especially cerebral infarction in our study population. Further studies are needed in different regions to determine the association between ambient air pollutants and acute cardiovascular fatalities.
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Cerebrovascular diseases · Jan 2012
Effect of combination therapy with the angiotensin receptor blocker losartan plus hydrochlorothiazide on brain perfusion in patients with both hypertension and cerebral hemodynamic impairment due to symptomatic chronic major cerebral artery steno-occlusive disease: a SPECT study.
While the combination of an angiotensin receptor blocker with thiazide diuretics produces a clinically beneficial reduction in blood pressure in patients who otherwise only partially respond to monotherapy with an angiotensin receptor blocker, blood pressure-lowering therapy with combination antihypertensive drug regimens in patients with cerebral hemodynamic impairment may adversely affect cerebral hemodynamics. The purpose of the present exploratory study was to determine whether blood pressure-lowering therapy with the combination of the angiotensin receptor blocker losartan plus hydrochlorothiazide (LPH) worsens brain perfusion in patients with both hypertension and cerebral hemodynamic impairment due to symptomatic chronic major cerebral artery steno-occlusive disease. ⋯ Although the present study was exploratory and its results were preliminary due to the small sample size, the current data suggest that blood pressure-lowering therapy with LPH apparently does not result in worsening of cerebral hemodynamics in patients with both hypertension and cerebral hemodynamic impairment due to symptomatic chronic ICA or MCA steno-occlusive disease.
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Cerebrovascular diseases · Jan 2012
Perfusion computed tomography-guided intravenous thrombolysis for acute ischemic stroke beyond 4.5 hours: a case-control study.
Extending the therapeutic window of intravenous thrombolysis for acute ischemic stroke beyond the established 4.5-hour limit is of critical importance in order to increase the proportion of thrombolysed stroke patients. In this setting, the capacity of MRI to select acute stroke patients for reperfusion therapies in delayed time windows has been and is being tested in clinical trials. However, whether the more available and cost-effective perfusion computed tomography (PCT) may be useful to select candidates for delayed intravenous thrombolysis remains largely unexplored. We aimed to evaluate the safety and efficacy of PCT-guided intravenous thrombolysis beyond 4.5 h after stroke onset. ⋯ Primary safety and efficacy endpoints were comparable between the early and delayed thrombolysis groups. The results of our exploratory study may justify a randomized clinical trial to test the safety and efficacy of PCT-guided intravenous thrombolysis in acute ischemic stroke patients presenting beyond 4.5 h from symptom onset.
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Cerebrovascular diseases · Jan 2012
Case ReportsLocal hemodynamics at the rupture point of cerebral aneurysms determined by computational fluid dynamics analysis.
Cerebral aneurysms carry a high risk of rupture and so present a major threat to the patient's life. Accurate criteria for predicting aneurysm rupture are important for therapeutic decision-making, and some clinical and morphological factors may help to predict the risk for rupture of unruptured aneurysms, such as sex, size and location. Hemodynamic forces are considered to be key in the natural history of cerebral aneurysms, but the effect on aneurysm rupture is uncertain, and whether low or high wall shear stress (WSS) is the most critical in promoting rupture remains extremely controversial. This study investigated the local hemodynamic features at the aneurysm rupture point. ⋯ The hemodynamics of 6 ruptured cerebral aneurysms of the middle cerebral artery were examined using retrospective CFD analysis. We could confirm the rupture points in all cases. With those findings, local hemodynamics of ruptured aneurysms were quanti-tatively investigated. The rupture point is located in a low WSS region of the aneurysm wall. Bleb-removed simulation showed increased WSS of the bleb-removed area, associated with the flow impaction area. Although the number of subjects in this study was relatively small, our findings suggest that the location of the rupture point is related to a low WSS at the aneurysm wall. Further investigations will elucidate the detailed hemodynamic effects on aneurysm rupture.