Pub Date : 2002-08-01DOI: 10.1161/01.STR.0000021002.17394.7F
J. L. Stork, K. Kimura, C. Levi, B. Chambers, A. Abbott, G. Donnan
Background and Purpose— In patients with both symptomatic and asymptomatic carotid artery stenoses, the relationship between carotid plaque characteristics and transcranial Doppler (TCD)–detected microembolic signals (MES) is unclear. The purpose of this study was to examine the relationship between macroscopically described plaque characteristics and MES in patients undergoing carotid endarterectomy. Methods— Sequential patients scheduled for carotid endarterectomy underwent preoperative 30-minute TCD monitoring of the ipsilateral middle cerebral artery to detect MES. TCD signal analysis, by researchers who were blinded to patient information, was performed offline. Clinical variables of patients and macroscopic carotid plaque features seen at surgery were documented prospectively. Results— Of the 109 patients (74 male, 35 female; mean age, 68.8±8.7 years) enrolled, 71 had ipsilateral carotid territory symptoms. MES were detected in 27 of all patients (25%). Twenty-two of 71 symptomatic patients (31%) compared with 5 of 38 asymptomatic patients (13%) had MES (P =0.046). Also, symptomatic patients had more emboli (total MES counts) than asymptomatic patients (P =0.010). The presence or absence of MES was not associated with plaque characteristics. Conclusions— Our data do not confirm previous reports of an association between MES and macroscopic plaque characteristics. We hypothesize that smaller platelet aggregates and fibrin clots, which are not detected macroscopically, are the most likely sources of TCD-detected MES.
{"title":"Source of Microembolic Signals in Patients With High-Grade Carotid Stenosis","authors":"J. L. Stork, K. Kimura, C. Levi, B. Chambers, A. Abbott, G. Donnan","doi":"10.1161/01.STR.0000021002.17394.7F","DOIUrl":"https://doi.org/10.1161/01.STR.0000021002.17394.7F","url":null,"abstract":"Background and Purpose— In patients with both symptomatic and asymptomatic carotid artery stenoses, the relationship between carotid plaque characteristics and transcranial Doppler (TCD)–detected microembolic signals (MES) is unclear. The purpose of this study was to examine the relationship between macroscopically described plaque characteristics and MES in patients undergoing carotid endarterectomy. Methods— Sequential patients scheduled for carotid endarterectomy underwent preoperative 30-minute TCD monitoring of the ipsilateral middle cerebral artery to detect MES. TCD signal analysis, by researchers who were blinded to patient information, was performed offline. Clinical variables of patients and macroscopic carotid plaque features seen at surgery were documented prospectively. Results— Of the 109 patients (74 male, 35 female; mean age, 68.8±8.7 years) enrolled, 71 had ipsilateral carotid territory symptoms. MES were detected in 27 of all patients (25%). Twenty-two of 71 symptomatic patients (31%) compared with 5 of 38 asymptomatic patients (13%) had MES (P =0.046). Also, symptomatic patients had more emboli (total MES counts) than asymptomatic patients (P =0.010). The presence or absence of MES was not associated with plaque characteristics. Conclusions— Our data do not confirm previous reports of an association between MES and macroscopic plaque characteristics. We hypothesize that smaller platelet aggregates and fibrin clots, which are not detected macroscopically, are the most likely sources of TCD-detected MES.","PeriodicalId":22274,"journal":{"name":"Stroke: Journal of the American Heart Association","volume":"160 1","pages":"2014-2018"},"PeriodicalIF":0.0,"publicationDate":"2002-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80115991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-01DOI: 10.1161/01.STR.0000021899.08659.C8
N. Tan, N. Venketasubramanian, S. Saw, H. Tjia
Background and Purpose— Hyperhomocyst(e)inemia is emerging as a possible risk factor for stroke, possibly because of accelerated atherosclerosis. There are no previous publications evaluating homocyst(e)ine in young Asian ischemic stroke patients. We conducted a case-control study examining homocyst(e)ine, vitamin B12, and folate levels in young, first-ever Asian ischemic stroke patients. Methods— We prospectively recruited 109 consecutive young (<50 years) first-ever hospitalized ischemic stroke patients and 88 age/gender-matched hospital-based controls during a period of 18 months. Prevalence of vascular risk factors was assessed; fasting homocyst(e)ine, vitamin B12, and folate were assayed. Stroke mechanisms were subtyped using TOAST study criteria. Results— Mean age was 43.8 (cases) and 43.1 (controls) years; 71.6% were male (cases and controls). Diabetes mellitus, hypertension, and hyperlipidemia were significantly more prevalent in cases. Mean fasting homocyst(e)ine levels were significantly higher in cases (13.7 &mgr;mol/L, 95% CI: 12.7 to 14.9) than controls (10.8 &mgr;mol/L, 95% CI: 9.9 to 11.8, P <0.001). Mean vitamin B12 levels were significantly lower in cases (299.5 pmol/L, 95% CI: 266.7 to 332.3) than controls (394.5 pmol/L, 95% CI: 357.9 to 431.0, P <0.001). Folate levels were not significantly different. Mean homocyst(e)ine levels were significantly elevated in large-artery strokes (16.9 &mgr;mol/L, 95% CI: 14.5 to 19.7, P <0.001) but not other stroke subtypes compared with controls. Compared with the lowest homocyst(e)ine quartile, the highest quartile was significantly associated with an adjusted odds ratio of 4.3 for ischemic stroke and 25.3 for large-artery stroke. Using a logistic regression model, the adjusted odds ratio was 5.17 (95% CI: 1.96 to 13.63, P =0.001) for every 1 &mgr;mol/L increase in log homocyst(e)ine. Conclusions— Hyperhomocyst(e)inemia is an independent risk factor for ischemic strokes in young Asian adults. The relationship between increasing homocyst(e)ine and stroke risk is strong, graded, and significant. The association with large-artery strokes suggests that hyperhomocyst(e)inemia may increase stroke risk via a proatherogenic effect.
{"title":"Hyperhomocyst(e)inemia and Risk of Ischemic Stroke Among Young Asian Adults","authors":"N. Tan, N. Venketasubramanian, S. Saw, H. Tjia","doi":"10.1161/01.STR.0000021899.08659.C8","DOIUrl":"https://doi.org/10.1161/01.STR.0000021899.08659.C8","url":null,"abstract":"Background and Purpose— Hyperhomocyst(e)inemia is emerging as a possible risk factor for stroke, possibly because of accelerated atherosclerosis. There are no previous publications evaluating homocyst(e)ine in young Asian ischemic stroke patients. We conducted a case-control study examining homocyst(e)ine, vitamin B12, and folate levels in young, first-ever Asian ischemic stroke patients. Methods— We prospectively recruited 109 consecutive young (<50 years) first-ever hospitalized ischemic stroke patients and 88 age/gender-matched hospital-based controls during a period of 18 months. Prevalence of vascular risk factors was assessed; fasting homocyst(e)ine, vitamin B12, and folate were assayed. Stroke mechanisms were subtyped using TOAST study criteria. Results— Mean age was 43.8 (cases) and 43.1 (controls) years; 71.6% were male (cases and controls). Diabetes mellitus, hypertension, and hyperlipidemia were significantly more prevalent in cases. Mean fasting homocyst(e)ine levels were significantly higher in cases (13.7 &mgr;mol/L, 95% CI: 12.7 to 14.9) than controls (10.8 &mgr;mol/L, 95% CI: 9.9 to 11.8, P <0.001). Mean vitamin B12 levels were significantly lower in cases (299.5 pmol/L, 95% CI: 266.7 to 332.3) than controls (394.5 pmol/L, 95% CI: 357.9 to 431.0, P <0.001). Folate levels were not significantly different. Mean homocyst(e)ine levels were significantly elevated in large-artery strokes (16.9 &mgr;mol/L, 95% CI: 14.5 to 19.7, P <0.001) but not other stroke subtypes compared with controls. Compared with the lowest homocyst(e)ine quartile, the highest quartile was significantly associated with an adjusted odds ratio of 4.3 for ischemic stroke and 25.3 for large-artery stroke. Using a logistic regression model, the adjusted odds ratio was 5.17 (95% CI: 1.96 to 13.63, P =0.001) for every 1 &mgr;mol/L increase in log homocyst(e)ine. Conclusions— Hyperhomocyst(e)inemia is an independent risk factor for ischemic strokes in young Asian adults. The relationship between increasing homocyst(e)ine and stroke risk is strong, graded, and significant. The association with large-artery strokes suggests that hyperhomocyst(e)inemia may increase stroke risk via a proatherogenic effect.","PeriodicalId":22274,"journal":{"name":"Stroke: Journal of the American Heart Association","volume":"19 1","pages":"1956-1962"},"PeriodicalIF":0.0,"publicationDate":"2002-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82515838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-01DOI: 10.1161/01.STR.0000023578.25318.B9
S. Kawaguchi, T. Sakaki, R. Uranishi
Background and Purpose— This article evaluates the intracranial venous hemodynamics of dural arteriovenous fistula (DAVF) on the basis of data from color Doppler flow imaging (CDFI) findings of the superior ophthalmic vein (SOV) and discusses the clinical application of the SOV CDFI to the DAVFs. Methods— We examined the diameter, flow direction, flow waveform, and flow velocity of the SOV using CDFI in 20 patients with intracranial DAVF. Six patients were asymptomatic; the other 14 patients were symptomatic. Angiographic retrograde cortical venous filling was seen in 14 patients. Results— In the DAVFs, the average SOV diameter was 2.95±1.15 mm, which was significantly broad compared with that of the control subjects (P <0.05). The flow direction was reversed in 2 patients and normal in the other 18 patients. Three patients showed an abnormal waveform. A reversed pulsatile waveform was observed in 2 patients, and a normograde pulsatile waveform was seen in 1 patient. The other 17 patients showed normal waveform. The average SOV diameter and resistance index values were significantly higher (P <0.05) in patients with clinical symptoms, angiographic retrograde cortical venous fillings, or large DAVFs compared with those in the other patients. Conclusions— The SOV CDFI findings in DAVFs correlated well with the patient’s clinical symptoms, angiographic findings, and DAVF size. These findings were useful to evaluate the intracranial venous hemodynamics in DAVFs.
{"title":"Color Doppler Flow Imaging of the Superior Ophthalmic Vein in Dural Arteriovenous Fistulas","authors":"S. Kawaguchi, T. Sakaki, R. Uranishi","doi":"10.1161/01.STR.0000023578.25318.B9","DOIUrl":"https://doi.org/10.1161/01.STR.0000023578.25318.B9","url":null,"abstract":"Background and Purpose— This article evaluates the intracranial venous hemodynamics of dural arteriovenous fistula (DAVF) on the basis of data from color Doppler flow imaging (CDFI) findings of the superior ophthalmic vein (SOV) and discusses the clinical application of the SOV CDFI to the DAVFs. Methods— We examined the diameter, flow direction, flow waveform, and flow velocity of the SOV using CDFI in 20 patients with intracranial DAVF. Six patients were asymptomatic; the other 14 patients were symptomatic. Angiographic retrograde cortical venous filling was seen in 14 patients. Results— In the DAVFs, the average SOV diameter was 2.95±1.15 mm, which was significantly broad compared with that of the control subjects (P <0.05). The flow direction was reversed in 2 patients and normal in the other 18 patients. Three patients showed an abnormal waveform. A reversed pulsatile waveform was observed in 2 patients, and a normograde pulsatile waveform was seen in 1 patient. The other 17 patients showed normal waveform. The average SOV diameter and resistance index values were significantly higher (P <0.05) in patients with clinical symptoms, angiographic retrograde cortical venous fillings, or large DAVFs compared with those in the other patients. Conclusions— The SOV CDFI findings in DAVFs correlated well with the patient’s clinical symptoms, angiographic findings, and DAVF size. These findings were useful to evaluate the intracranial venous hemodynamics in DAVFs.","PeriodicalId":22274,"journal":{"name":"Stroke: Journal of the American Heart Association","volume":"2 1","pages":"2009-2013"},"PeriodicalIF":0.0,"publicationDate":"2002-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90080828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-01DOI: 10.1161/01.STR.0000023888.43488.10
H. Naess, H. Nyland, L. Thomassen, J. Aarseth, G. Nyland, K. Myhr
Background and Purpose— We sought to determine the incidence and short-term outcome of people aged 15 to 49 years with first-ever cerebral infarction in 1988–1997 in Hordaland County, Norway. Methods— Cases were found from computer search of hospital registries and detailed review of patient records. Stroke subtype was classified according to the major intracranial artery affected. Short-term outcome was evaluated by the modified Rankin Scale (mRS). Results— A total of 96 women and 136 men met the inclusion criteria. The average annual incidence was 11.4/100 000. Women outnumbered men among those aged <30 years (P =0.059); men predominated among those aged ≥30 years (P =0.004). A total of 148 patients had anterior circulation infarction (64%), and 84 had posterior circulation infarction (36%) (P <0.001). Patients with posterior circulation infarction had better mRS score at discharge (P =0.005). Eighty percent had favorable outcome (mRS score ≤2). The 30-day case fatality rate was 3.4%. The recurrence rate in hospital was 2.2%. Conclusions— The incidence was in the lower range compared with other reports from western Europe. Although men predominated, there was a strong trend toward more women among patients aged <30 years. Short-term outcome was generally good. Patients with posterior circulation infarction had significantly better short-term outcome.
{"title":"Incidence and Short-Term Outcome of Cerebral Infarction in Young Adults in Western Norway","authors":"H. Naess, H. Nyland, L. Thomassen, J. Aarseth, G. Nyland, K. Myhr","doi":"10.1161/01.STR.0000023888.43488.10","DOIUrl":"https://doi.org/10.1161/01.STR.0000023888.43488.10","url":null,"abstract":"Background and Purpose— We sought to determine the incidence and short-term outcome of people aged 15 to 49 years with first-ever cerebral infarction in 1988–1997 in Hordaland County, Norway. Methods— Cases were found from computer search of hospital registries and detailed review of patient records. Stroke subtype was classified according to the major intracranial artery affected. Short-term outcome was evaluated by the modified Rankin Scale (mRS). Results— A total of 96 women and 136 men met the inclusion criteria. The average annual incidence was 11.4/100 000. Women outnumbered men among those aged <30 years (P =0.059); men predominated among those aged ≥30 years (P =0.004). A total of 148 patients had anterior circulation infarction (64%), and 84 had posterior circulation infarction (36%) (P <0.001). Patients with posterior circulation infarction had better mRS score at discharge (P =0.005). Eighty percent had favorable outcome (mRS score ≤2). The 30-day case fatality rate was 3.4%. The recurrence rate in hospital was 2.2%. Conclusions— The incidence was in the lower range compared with other reports from western Europe. Although men predominated, there was a strong trend toward more women among patients aged <30 years. Short-term outcome was generally good. Patients with posterior circulation infarction had significantly better short-term outcome.","PeriodicalId":22274,"journal":{"name":"Stroke: Journal of the American Heart Association","volume":"30 1","pages":"2105-2108"},"PeriodicalIF":0.0,"publicationDate":"2002-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87253740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-01DOI: 10.1161/01.STR.0000020712.84444.8D
M. Cipolla, A. Curry
Background and Purpose— Myogenic activity of the cerebral arteries is an important contributor to autoregulation of cerebral blood flow. Previous studies have demonstrated that increasing periods of ischemia diminished the amount of myogenic tone in cerebral arteries. In the present study, we investigated the effect of different periods of postischemic reperfusion on the myogenic behavior of middle cerebral arteries (MCAs). We measured both the amount of spontaneous myogenic tone that developed at 75 mm Hg and the contractile response to increased transmural pressure (TMP), ie, myogenic reactivity. Methods— The MCA occlusion model was used in male Wistar rats (n=45) to induce 30 minutes of temporary ischemia, followed by different periods of reperfusion (0 or sham; 30 minutes; and 6, 12, 18, 20, and 22 hours), confirmed by laser Doppler flowmetry. MCAs were studied in vitro using an arteriograph system that allowed control of TMP and measurement of lumen diameter. After equilibration for 1 hour at 75 mm Hg, TMP was increased stepwise in 25–mm Hg increments to 125 mm Hg and lumen diameter measured at each pressure. The amount of spontaneous myogenic tone was determined in both ischemic and contralateral arteries for each reperfusion period and compared with the right and left MCAs in the sham group. Arteries were then fixed with 10% formalin pressurized in the arteriograph bath and stained for filamentous (F)–actin with fluorescently labeled phalloidin, a specific probe for F-actin. The amount of F-actin was quantified using confocal microscopy. Results— MCAs from the sham-operated control group possessed considerable myogenic tone (35%). However, the amount of tone in ischemic MCAs progressively diminished as the reperfusion duration increased. In addition, sham-operated control arteries responded myogenically to increases in TMP, decreasing diameter as pressure increased. There was a similar response in arteries exposed to 30 minutes and 6 hours of reperfusion, all producing a negative slope on the pressure-diameter curve; however, myogenic reactivity was diminished at the longer periods of reperfusion, producing a positive slope of the graph. The slopes of the pressure-diameter curves were as follows: −0.10±−0.06 (sham), −0.07±−0.12 (30 minutes), −0.08±−0.11 (6 hours), +0.09±0.09 (12 hours), +0.25±0.16 (18 hours), +0.38±0.09 (20 hours), and +0.57±0.09 (22 hours). F-actin content was significantly less only in ischemic MCAs at 6 and 12 hours of reperfusion. Conclusions— These results demonstrate that longer periods of reperfusion significantly diminish myogenic activity of MCAs. Understanding how different periods of ischemia and reperfusion affect the function of the cerebral circulation may promote more effective treatment of ischemic stroke.
{"title":"Middle Cerebral Artery Function After Stroke: The Threshold Duration of Reperfusion for Myogenic Activity","authors":"M. Cipolla, A. Curry","doi":"10.1161/01.STR.0000020712.84444.8D","DOIUrl":"https://doi.org/10.1161/01.STR.0000020712.84444.8D","url":null,"abstract":"Background and Purpose— Myogenic activity of the cerebral arteries is an important contributor to autoregulation of cerebral blood flow. Previous studies have demonstrated that increasing periods of ischemia diminished the amount of myogenic tone in cerebral arteries. In the present study, we investigated the effect of different periods of postischemic reperfusion on the myogenic behavior of middle cerebral arteries (MCAs). We measured both the amount of spontaneous myogenic tone that developed at 75 mm Hg and the contractile response to increased transmural pressure (TMP), ie, myogenic reactivity. Methods— The MCA occlusion model was used in male Wistar rats (n=45) to induce 30 minutes of temporary ischemia, followed by different periods of reperfusion (0 or sham; 30 minutes; and 6, 12, 18, 20, and 22 hours), confirmed by laser Doppler flowmetry. MCAs were studied in vitro using an arteriograph system that allowed control of TMP and measurement of lumen diameter. After equilibration for 1 hour at 75 mm Hg, TMP was increased stepwise in 25–mm Hg increments to 125 mm Hg and lumen diameter measured at each pressure. The amount of spontaneous myogenic tone was determined in both ischemic and contralateral arteries for each reperfusion period and compared with the right and left MCAs in the sham group. Arteries were then fixed with 10% formalin pressurized in the arteriograph bath and stained for filamentous (F)–actin with fluorescently labeled phalloidin, a specific probe for F-actin. The amount of F-actin was quantified using confocal microscopy. Results— MCAs from the sham-operated control group possessed considerable myogenic tone (35%). However, the amount of tone in ischemic MCAs progressively diminished as the reperfusion duration increased. In addition, sham-operated control arteries responded myogenically to increases in TMP, decreasing diameter as pressure increased. There was a similar response in arteries exposed to 30 minutes and 6 hours of reperfusion, all producing a negative slope on the pressure-diameter curve; however, myogenic reactivity was diminished at the longer periods of reperfusion, producing a positive slope of the graph. The slopes of the pressure-diameter curves were as follows: −0.10±−0.06 (sham), −0.07±−0.12 (30 minutes), −0.08±−0.11 (6 hours), +0.09±0.09 (12 hours), +0.25±0.16 (18 hours), +0.38±0.09 (20 hours), and +0.57±0.09 (22 hours). F-actin content was significantly less only in ischemic MCAs at 6 and 12 hours of reperfusion. Conclusions— These results demonstrate that longer periods of reperfusion significantly diminish myogenic activity of MCAs. Understanding how different periods of ischemia and reperfusion affect the function of the cerebral circulation may promote more effective treatment of ischemic stroke.","PeriodicalId":22274,"journal":{"name":"Stroke: Journal of the American Heart Association","volume":"464 1","pages":"2094-2099"},"PeriodicalIF":0.0,"publicationDate":"2002-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83006856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-01DOI: 10.1161/01.STR.0000023534.37670.F7
R. Dijkhuizen, M. Asahi, O. Wu, B. Rosen, E. Lo
Background and Purpose— Thrombolytic therapy with recombinant tissue plasminogen activator (rtPA) after stroke increases risk of hemorrhagic transformation, particularly in areas with blood-brain barrier leakage. Our aim was to characterize acute effects of rtPA administration on the integrity of microvascular barriers. Methods— Stroke was induced in spontaneously hypertensive rats by unilateral embolic middle cerebral artery occlusion. Six hours after stroke, rtPA was intravenously administered (n=10). Controls received saline (n=4). Extravasation of the large-diameter contrast agent monocrystalline iron oxide nanocolloid (MION) was assessed with susceptibility contrast-enhanced MRI during rtPA injection. In addition, we performed perfusion MRI and diffusion-weighted MRI. After MRI, 2 hours after rtPA treatment, intracerebral hemorrhage was quantified with a spectrophotometric hemoglobin assay. Results— Late rtPA treatment resulted in increased hemorrhage volume (8.4±1.7 versus 2.9±0.9 &mgr;L in controls;P <0.05). In MION-injected animals, during rtPA administration, transverse relaxation rate change (&Dgr;R2*) increased from 12.4±6.0 to 31.6±19.2 s−1 (P <0.05) in areas with subsequent hemorrhage. Significant &Dgr;R2* changes were absent in nonhemorrhagic areas, in animals without injected MION, and in saline-treated animals. Thrombolytic therapy did not improve perfusion in regions with hemorrhagic transformation (cerebral blood flow index was 22.8±19.7% [of contralateral] at 0.5 hours before and 22.4±18.0% at 1 hour after rtPA administration). Conclusions— The &Dgr;R2* changes during rtPA delivery in MION-injected animals indicate extravasation of MION, which reflects increased permeability of the blood-brain barrier. This implies that late rtPA treatment rapidly aggravates early ischemia-induced damage to microvascular barriers, thereby enhancing hemorrhagic transformation.
{"title":"Rapid Breakdown of Microvascular Barriers and Subsequent Hemorrhagic Transformation After Delayed Recombinant Tissue Plasminogen Activator Treatment in a Rat Embolic Stroke Model","authors":"R. Dijkhuizen, M. Asahi, O. Wu, B. Rosen, E. Lo","doi":"10.1161/01.STR.0000023534.37670.F7","DOIUrl":"https://doi.org/10.1161/01.STR.0000023534.37670.F7","url":null,"abstract":"Background and Purpose— Thrombolytic therapy with recombinant tissue plasminogen activator (rtPA) after stroke increases risk of hemorrhagic transformation, particularly in areas with blood-brain barrier leakage. Our aim was to characterize acute effects of rtPA administration on the integrity of microvascular barriers. Methods— Stroke was induced in spontaneously hypertensive rats by unilateral embolic middle cerebral artery occlusion. Six hours after stroke, rtPA was intravenously administered (n=10). Controls received saline (n=4). Extravasation of the large-diameter contrast agent monocrystalline iron oxide nanocolloid (MION) was assessed with susceptibility contrast-enhanced MRI during rtPA injection. In addition, we performed perfusion MRI and diffusion-weighted MRI. After MRI, 2 hours after rtPA treatment, intracerebral hemorrhage was quantified with a spectrophotometric hemoglobin assay. Results— Late rtPA treatment resulted in increased hemorrhage volume (8.4±1.7 versus 2.9±0.9 &mgr;L in controls;P <0.05). In MION-injected animals, during rtPA administration, transverse relaxation rate change (&Dgr;R2*) increased from 12.4±6.0 to 31.6±19.2 s−1 (P <0.05) in areas with subsequent hemorrhage. Significant &Dgr;R2* changes were absent in nonhemorrhagic areas, in animals without injected MION, and in saline-treated animals. Thrombolytic therapy did not improve perfusion in regions with hemorrhagic transformation (cerebral blood flow index was 22.8±19.7% [of contralateral] at 0.5 hours before and 22.4±18.0% at 1 hour after rtPA administration). Conclusions— The &Dgr;R2* changes during rtPA delivery in MION-injected animals indicate extravasation of MION, which reflects increased permeability of the blood-brain barrier. This implies that late rtPA treatment rapidly aggravates early ischemia-induced damage to microvascular barriers, thereby enhancing hemorrhagic transformation.","PeriodicalId":22274,"journal":{"name":"Stroke: Journal of the American Heart Association","volume":"152 1","pages":"2100-2104"},"PeriodicalIF":0.0,"publicationDate":"2002-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86227589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-01DOI: 10.1161/01.STR.0000022808.21776.BF
C. Weimar, T. Kurth, K. Kraywinkel, M. Wagner, O. Busse, R. Haberl, H. Diener
Background and Purpose— Functioning and disability after ischemic stroke are clinically meaningful and of major relevance to patients. Despite many instruments available to assess these outcomes, little is known about their interrelation and predictive factors. Methods— We prospectively identified 4264 patients with acute ischemic stroke from 30 hospitals in Germany during a 1-year period between 1998 and 1999 and registered them in a common data bank. The patients were centrally followed up via telephone interview after 100 days and 1 year to assess various scales such as the Barthel Index (BI), modified Rankin Scale (MRS), extended Barthel Index (EBI), Short Form-36 Physical Functioning (SF-36 PF), and Center for Epidemiologic Studies–Depression short form (CES-D). Results— Outcome status could be assessed in 67.2% of patients 100 days after hospital admission. Of these, 13.9% had died, 53.7% had regained functional independence (BI <95), 46.3% had no or mild residual symptoms (MRS ≤1), and 44.6% had no higher cognitive deficits on the EBI. Of the patients who personally answered the follow-up questions, 67% had no major physical disability (SF-36 PF <60), and 32.9% reported symptoms classified as depression (CES-D ≥10). The high percentage of patients reaching the maximum score (ceiling effect) in the BI was less pronounced in the MRS and SF-36 PF. The predictive factors for dichotomized outcomes on each scale were similar for adverse functioning and disability but varied considerably for depression. Conclusions— To avoid ceiling effects in outcome distribution of patients treated in specialized stroke centers, the MRS and SF-36 PF instruments are preferable to the BI. Parametric use of the SF-36 PF could further improve outcome measurement by considering individual treatment effects.
{"title":"Assessment of Functioning and Disability After Ischemic Stroke","authors":"C. Weimar, T. Kurth, K. Kraywinkel, M. Wagner, O. Busse, R. Haberl, H. Diener","doi":"10.1161/01.STR.0000022808.21776.BF","DOIUrl":"https://doi.org/10.1161/01.STR.0000022808.21776.BF","url":null,"abstract":"Background and Purpose— Functioning and disability after ischemic stroke are clinically meaningful and of major relevance to patients. Despite many instruments available to assess these outcomes, little is known about their interrelation and predictive factors. Methods— We prospectively identified 4264 patients with acute ischemic stroke from 30 hospitals in Germany during a 1-year period between 1998 and 1999 and registered them in a common data bank. The patients were centrally followed up via telephone interview after 100 days and 1 year to assess various scales such as the Barthel Index (BI), modified Rankin Scale (MRS), extended Barthel Index (EBI), Short Form-36 Physical Functioning (SF-36 PF), and Center for Epidemiologic Studies–Depression short form (CES-D). Results— Outcome status could be assessed in 67.2% of patients 100 days after hospital admission. Of these, 13.9% had died, 53.7% had regained functional independence (BI <95), 46.3% had no or mild residual symptoms (MRS ≤1), and 44.6% had no higher cognitive deficits on the EBI. Of the patients who personally answered the follow-up questions, 67% had no major physical disability (SF-36 PF <60), and 32.9% reported symptoms classified as depression (CES-D ≥10). The high percentage of patients reaching the maximum score (ceiling effect) in the BI was less pronounced in the MRS and SF-36 PF. The predictive factors for dichotomized outcomes on each scale were similar for adverse functioning and disability but varied considerably for depression. Conclusions— To avoid ceiling effects in outcome distribution of patients treated in specialized stroke centers, the MRS and SF-36 PF instruments are preferable to the BI. Parametric use of the SF-36 PF could further improve outcome measurement by considering individual treatment effects.","PeriodicalId":22274,"journal":{"name":"Stroke: Journal of the American Heart Association","volume":"69 1","pages":"2053-2059"},"PeriodicalIF":0.0,"publicationDate":"2002-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90246233","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-01DOI: 10.1161/01.STR.0000023576.94311.27
P. Turkington, J. Bamford, P. Wanklyn, M. Elliott
Background and Purpose— The prevalence of sleep-disordered breathing after stroke has been reported to be between 32% and 71%. However, the first 24-hour period, when upper airway obstruction may have a critical effect on the cerebral circulation because of hemodynamic fluctuations and repetitive hypoxia, has not been studied. Furthermore, data on prediction of upper airway obstruction after stroke are limited. This study sought to assess the prevalence of upper airway obstruction in the first 24 hours of stroke and to ascertain whether its occurrence could be predicted. Methods— One hundred twenty patients with acute stroke underwent a respiratory variable-only sleep study, started within 24 hours of onset of neurological symptoms. Sleep history and stroke characteristics were recorded on admission. Results— We found that 79%, 61%, and 45% of the patients had a respiratory disturbance index greater than 5, 10, and 15 events per hour, respectively. Patients had a significantly higher respiratory disturbance index when nursed in the supine (29 events per hour), supine left (29 events per hour), and supine right (24 events per hour) positions than in any other position (P <0.0001). On logistic regression analysis, BMI (P =0.025), neck circumference (P =0.026), and limb weakness (P =0.025) independently predicted the occurrence of upper airway obstruction in the first 24 hours after acute stroke. Conclusions— Upper airway obstruction is common in the first 24 hours after stroke, especially if patients are nursed in the supine position, and typical obstructive sleep apnea risk factors (body mass index and neck circumference) appear to be the best predictors of its occurrence. Stroke characteristics (severity, clinical subtype, and clinically assessed pharyngeal function) are not independently associated with upper airway obstruction after stroke.
{"title":"Prevalence and Predictors of Upper Airway Obstruction in the First 24 Hours After Acute Stroke","authors":"P. Turkington, J. Bamford, P. Wanklyn, M. Elliott","doi":"10.1161/01.STR.0000023576.94311.27","DOIUrl":"https://doi.org/10.1161/01.STR.0000023576.94311.27","url":null,"abstract":"Background and Purpose— The prevalence of sleep-disordered breathing after stroke has been reported to be between 32% and 71%. However, the first 24-hour period, when upper airway obstruction may have a critical effect on the cerebral circulation because of hemodynamic fluctuations and repetitive hypoxia, has not been studied. Furthermore, data on prediction of upper airway obstruction after stroke are limited. This study sought to assess the prevalence of upper airway obstruction in the first 24 hours of stroke and to ascertain whether its occurrence could be predicted. Methods— One hundred twenty patients with acute stroke underwent a respiratory variable-only sleep study, started within 24 hours of onset of neurological symptoms. Sleep history and stroke characteristics were recorded on admission. Results— We found that 79%, 61%, and 45% of the patients had a respiratory disturbance index greater than 5, 10, and 15 events per hour, respectively. Patients had a significantly higher respiratory disturbance index when nursed in the supine (29 events per hour), supine left (29 events per hour), and supine right (24 events per hour) positions than in any other position (P <0.0001). On logistic regression analysis, BMI (P =0.025), neck circumference (P =0.026), and limb weakness (P =0.025) independently predicted the occurrence of upper airway obstruction in the first 24 hours after acute stroke. Conclusions— Upper airway obstruction is common in the first 24 hours after stroke, especially if patients are nursed in the supine position, and typical obstructive sleep apnea risk factors (body mass index and neck circumference) appear to be the best predictors of its occurrence. Stroke characteristics (severity, clinical subtype, and clinically assessed pharyngeal function) are not independently associated with upper airway obstruction after stroke.","PeriodicalId":22274,"journal":{"name":"Stroke: Journal of the American Heart Association","volume":"12 1","pages":"2037-2042"},"PeriodicalIF":0.0,"publicationDate":"2002-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88032084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-01DOI: 10.1161/01.STR.0000023491.63693.18
W. Schäbitz, A. Giuffrida, C. Berger, A. Aschoff, M. Schwaninger, S. Schwab, D. Piomelli
Background— Excitotoxic insults such as stroke may induce release of fatty acid ethanolamides (FAEs), contributing to the downstream events in the ischemic cascade. We therefore studied release of FAEs such as anandamide, palmitylethanolamide (PEA), and oleylethanolamide (OEA) in the brain of a patient suffering from malignant hemispheric infarction treated with hypothermia. Case Description— A patient with life-threatening hemispheric stroke was treated with moderate hypothermia (33°C) that was maintained for 3 days, followed by a 3-day rewarming period. Microdialysis was applied to measure glutamate, lactate, and glycerol by using a microdialysis analyzer. FAEs were measured by microdialysis coupled with high-performance liquid chromatography/mass spectrometry. Release of neuroprotective fatty amides occurred within the first day after ischemia and reached high concentrations for all 3 substances in tissue surrounding the primary ischemic lesion: anandamide up to 42 pmol/mL, PEA up to 120 pmol/mL, and OEA up to 242 pmol/mL. There was a significant correlation with elevation of lactate as early marker for the hypoxic insult. Conclusions— This is the first report demonstrating release of FAEs in vivo during human stroke and may suggest contribution of the FAE signaling system to the pathophysiological events after ischemia.
{"title":"Release of Fatty Acid Amides in a Patient With Hemispheric Stroke: A Microdialysis Study","authors":"W. Schäbitz, A. Giuffrida, C. Berger, A. Aschoff, M. Schwaninger, S. Schwab, D. Piomelli","doi":"10.1161/01.STR.0000023491.63693.18","DOIUrl":"https://doi.org/10.1161/01.STR.0000023491.63693.18","url":null,"abstract":"Background— Excitotoxic insults such as stroke may induce release of fatty acid ethanolamides (FAEs), contributing to the downstream events in the ischemic cascade. We therefore studied release of FAEs such as anandamide, palmitylethanolamide (PEA), and oleylethanolamide (OEA) in the brain of a patient suffering from malignant hemispheric infarction treated with hypothermia. Case Description— A patient with life-threatening hemispheric stroke was treated with moderate hypothermia (33°C) that was maintained for 3 days, followed by a 3-day rewarming period. Microdialysis was applied to measure glutamate, lactate, and glycerol by using a microdialysis analyzer. FAEs were measured by microdialysis coupled with high-performance liquid chromatography/mass spectrometry. Release of neuroprotective fatty amides occurred within the first day after ischemia and reached high concentrations for all 3 substances in tissue surrounding the primary ischemic lesion: anandamide up to 42 pmol/mL, PEA up to 120 pmol/mL, and OEA up to 242 pmol/mL. There was a significant correlation with elevation of lactate as early marker for the hypoxic insult. Conclusions— This is the first report demonstrating release of FAEs in vivo during human stroke and may suggest contribution of the FAE signaling system to the pathophysiological events after ischemia.","PeriodicalId":22274,"journal":{"name":"Stroke: Journal of the American Heart Association","volume":"9 1","pages":"2112-2114"},"PeriodicalIF":0.0,"publicationDate":"2002-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87494383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-08-01DOI: 10.1161/01.STR.0000020841.74704.5B
R. Gerraty, M. Parsons, P. Barber, D. Darby, P. Desmond, B. Tress, S. Davis
Background— The clinical diagnosis of subcortical cerebral infarction is inaccurate for lesion location and pathogenesis. Clinically suspected small perforating artery occlusions may be embolic infarcts, with important implications for investigation and treatment. New MRI techniques may allow more accurate determination of the stroke mechanism soon after admission. Methods— In a prospective series of 106 patients evaluated with acute diffusion-weighted MRI (DWI) and perfusion-weighted MRI (PWI) within 24 hours of stroke, we enrolled 19 with a lacunar syndrome. On the basis of the topography, DWI and PWI findings, and outcome T2 MRI, we determined whether the mechanism of infarction was single perforating vessel occlusion or large artery embolism. Results— Thirteen patients had pure motor stroke, 2 had ataxic hemiparesis, and 4 had sensorimotor stroke. Six patients had lacunes on MRI, none with PWI lesions. Four patients had subcortical and distal cortical infarcts on DWI. Nine had solitary restricted striatocapsular infarcts. Seven of these 9 had PWI studies, 5 with PWI lesions. The presence of a PWI lesion reliably differentiated striatocapsular from lacunar infarction for solitary small subcortical infarcts (P =0.03). Conclusion— DWI and PWI altered the final diagnosis of infarct pathogenesis from small perforating artery occlusion to large artery embolism in 13 of 19 patients presenting with lacunar syndromes. Lacunes cannot be reliably diagnosed on clinical grounds.
{"title":"Examining the Lacunar Hypothesis With Diffusion and Perfusion Magnetic Resonance Imaging","authors":"R. Gerraty, M. Parsons, P. Barber, D. Darby, P. Desmond, B. Tress, S. Davis","doi":"10.1161/01.STR.0000020841.74704.5B","DOIUrl":"https://doi.org/10.1161/01.STR.0000020841.74704.5B","url":null,"abstract":"Background— The clinical diagnosis of subcortical cerebral infarction is inaccurate for lesion location and pathogenesis. Clinically suspected small perforating artery occlusions may be embolic infarcts, with important implications for investigation and treatment. New MRI techniques may allow more accurate determination of the stroke mechanism soon after admission. Methods— In a prospective series of 106 patients evaluated with acute diffusion-weighted MRI (DWI) and perfusion-weighted MRI (PWI) within 24 hours of stroke, we enrolled 19 with a lacunar syndrome. On the basis of the topography, DWI and PWI findings, and outcome T2 MRI, we determined whether the mechanism of infarction was single perforating vessel occlusion or large artery embolism. Results— Thirteen patients had pure motor stroke, 2 had ataxic hemiparesis, and 4 had sensorimotor stroke. Six patients had lacunes on MRI, none with PWI lesions. Four patients had subcortical and distal cortical infarcts on DWI. Nine had solitary restricted striatocapsular infarcts. Seven of these 9 had PWI studies, 5 with PWI lesions. The presence of a PWI lesion reliably differentiated striatocapsular from lacunar infarction for solitary small subcortical infarcts (P =0.03). Conclusion— DWI and PWI altered the final diagnosis of infarct pathogenesis from small perforating artery occlusion to large artery embolism in 13 of 19 patients presenting with lacunar syndromes. Lacunes cannot be reliably diagnosed on clinical grounds.","PeriodicalId":22274,"journal":{"name":"Stroke: Journal of the American Heart Association","volume":"85 1","pages":"2019-2024"},"PeriodicalIF":0.0,"publicationDate":"2002-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80006834","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：