[Show abstract][Hide abstract] ABSTRACT: Pivotal clinical trials suggest that intravenous (IV) recombinant tissue plasminogen activator (rt-PA) benefits stroke patients regardless of the underlying etiology. Paradoxical strokes, presumed to be caused by fibrin-rich clots originating in the venous circulation, may respond better to fibrinolysis than other ischemic stroke subtypes. In this study, we compared the response with IV rt-PA in paradoxical stroke patients and other stroke subtypes.
In total, 486 patients treated with IV rt-PA at a single institution were retrospectively reviewed. Adjudication of stroke mechanism was based on chart review. Five major stroke mechanisms-cardioembolic, artery-to-artery emboli, lacunar, cryptogenic, and paradoxical-were identified by final diagnosis from chart reviews. Mimics, undefined etiology, and defined etiology not falling into the major mechanisms were excluded. Analysis of variance and general linear model were used to assess the differences between groups.
A total of 323 patients were analyzed. We found significant differences in clinical outcome between stroke mechanisms, including discharge National Institutes of Health Stroke Scale (NIHSS) (P = .007), discharge Rankin (P = .011), discharge disposition (P = .000), and infarct volume (P = .007). Post hoc analysis showed that cardioembolic patients had the worst outcomes (discharge NIHSS score 11.12 ± 12.26), whereas paradoxical strokes had the best outcomes (discharge NIHSS score 3.67 ± 4.90), but these did not approach statistical significance. However, regression analysis showed that 4 variables-congestive heart failure, admission NIHSS, age, and mean infarct volume-rather than stroke mechanism were the true predictors of poor outcome.
Paradoxical strokes had better outcomes after IV fibrinolysis than other ischemic stroke subtypes, but this difference is attributable to younger age and milder stroke severity on presentation.
Journal of stroke and cerebrovascular diseases: the official journal of National Stroke Association 07/2013; 22(8). DOI:10.1016/j.jstrokecerebrovasdis.2013.05.022 · 1.67 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background:
There is limited experience in the community with intravenous tissue plasminogen activator (rt-PA) administered 3 to 4.5 hours after acute ischemic stroke (AIS) onset. Many patients do not meet entry criteria of pivotal clinical trials because of severe stroke, age >80, severe hypertension (sHTN), or history of previous stroke and diabetes. Whether rt-PA benefits these patients is unclear. Thus, we investigated the outcomes of stroke patients treated with rt-PA with or without these adverse clinical characteristics.
Chart review of patients with AIS treated with intravenous rt-PA at a single institution. Outcomes at discharge were compared between patients with severe stroke, age >80, sHTN, or previous stroke/diabetes and those without these characteristics. Good outcome was defined as modified Rankin score (mRS) of 0 to 1. Analysis of variance and t tests were used to compare the outcomes.
Of the 118 cases analyzed, 103 (87%) were treated ≤3 hours and 15 (13%) between 3 and 4.5 hours. Sixty-three (53%) patients had severe stroke, age >80, sHTN, or previous stroke/diabetes, whereas 55 (47%) did not. Compared to controls, patients with these adverse characteristics were less likely to have good outcomes (35% vs 56%, p = .02). No patients treated within the 3- to 4.5-hour window experienced symptomatic intracranial hemorrhage (sICH). Eight patients treated between 3 and 4.5 hours had severe stroke, age >80, sHTN, or previous stroke/diabetes. Of these, 6 had poor outcomes.
In a highly selected group of patients treated with intravenous rt-PA, lack of adherence to current guidelines did not improve stroke outcomes. This was related to more severe strokes at baseline, not sICH. Prospective studies of this patient group are needed.
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: Many patients with stroke-mimicking conditions receive treatment with intravenous fibrinolysis (IVF), a treatment associated with potentially serious complications. We sought to determine if any clinical or radiographic characteristics can help predict stroke mimics among IVF candidates. METHODS: This retrospective study was carried out at a single institution. Patients treated with intravenous recombinant tissue plasminogen activator (rt-PA; n = 193) were divided into 3 categories: acute ischemic stroke (n = 142), aborted stroke (n = 21), and stroke mimics (n = 30). Analysis of variance and the chi-square test were used to assess differences, while logistic regression models were computed to predict groups. RESULTS: Mimics treated with rt-PA did not experience complications (intracranial bleeding, systemic hemorrhage, or angioedema), and had better neurologic and functional outcomes than stroke patients (P < .05). Several variables helped differentiate strokes from mimics, including atherosclerosis on computed tomographic angiography (odds ratio [OR] 23.6; 95% confidence interval [CI] 8.4-66.2), atrial fibrillation (OR 11.4; 95% CI 1.5-86.3), age >50 years (OR 7.2; 95% CI 2.8-18.5), and focal weakness (OR 4.15; 95% CI 1.75-9.8). Other variables decreased chances of stroke: migraine history (OR 0.05; 95% CI 0.01-0.4), epilepsy (OR 0.13; 95% CI 0.02-0.8), paresthesia (OR 0.1; 95% CI 0.04-0.3), and precordialgia (OR 0.045; 95% CI 0.002-0.9). A regression model using focal weakness, computed tomographic angiography findings, and precordialgia had a 90.2% predictive accuracy. CONCLUSIONS: IVF has low complication rates in stroke mimics. Certain clinical characteristics appear predictive of stroke mimics, particularly normal computed tomographic angiography. If confirmed, this may help prevent giving IVF to patients without stroke.
Journal of stroke and cerebrovascular diseases: the official journal of National Stroke Association 06/2011; 21(8). DOI:10.1016/j.jstrokecerebrovasdis.2011.04.018 · 1.67 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Neurohospitalists represent an emerging neurological subspecialty focusing on inpatient neurological disease. Little data exists regarding neurohospitalist practice information and clinical activity. A survey among neurohospitalists was performed to help define the subspecialty, yield demographic information, practice characteristics, and understand clinical and non-clinical activities. During the formation the Neurohospitalist Section of the American Academy of Neurology September 2008, an online survey (29 questions mixed categorical, numerical, and free text) of 93 neurohospitalists was performed. The survey closed on October 13, 2008. The survey achieved a 54% response rate. Eighty-two percent of respondents were male, mean age 42 (range, 34-68), median practice duration 6 years, with broad distribution of practices across the US. Seventy-five percent of respondents reported having general neurology residency plus additional fellowship training (54% vascular neurology fellowship, 13% neurocritical care, and 33% other no response). Fifty-one percent of neurohospitalists were hired by non-academic (private) institutions, whereas academic institutions hired 49%. There was a wide array of responses for call frequency, duration, number of practice partners, and annual income. A uniform definition of the neurohospitalist subspecialty emerged as one who cares for inpatients, focusing primarily on in-hospital responsibilities. Neurohospitalists defined themselves as inpatient neurological subspecialists. Neurohospitalists have a broad US geographic distribution (and possibly international), in both academic and private practice (or hybrid) forms, and typically provide inpatient and Emergency Department (ED) call coverage for hospitals or outpatient neurologic practices. Most neurohospitalists were involved in administrative aspects of stroke or inpatient quality initiatives.
Frontiers in Neurology 06/2010; 1:9. DOI:10.3389/fneur.2010.00009
[Show abstract][Hide abstract] ABSTRACT: Cellular phone conversations between on-scene patients or their legally authorized representatives (LARs) and off-scene enrolling physician-investigators require immediate and reliable connection systems to obtain explicit informed research consent in prehospital treatment trials.
The NIH Field Administration of Stroke Therapy-Magnesium (FAST-MAG) Trial implemented a voice-over-internet protocol (VOIP) simultaneous ring system (multiple investigator cell phones called simultaneously and first responder connected to call) to enable physician-investigators to elicit consent immediately from competent patients or LARs encountered by 228 ambulances enrolling patients in a multicenter prehospital stroke trial. For 1 month, the number, origin, duration, and yield of enrolling line calls were monitored prospectively.
Six investigators were connected to 106 enrolling line calls, with no identified unanswered calls. Thirty-five percent of new patient calls yielded an enrollment. The most common reasons for non-enrollment were last known well >2 h (n = 7) and unconsentable patient without LAR available (n = 7). No non-enrollments were directly attributable to the VOIP system. In enrollments, consent was provided by the patient in 67% and a LAR in 33%. The duration of enrollment calls (mean +/- SD: 8.4 +/- 2.5 min, range 6-14) was longer than non-enrollment calls (5.5 +/- 3.5, range 2-13; p < 0.001). The median interval from last known well to study agent start was 46 min, and 70% were enrolled within 60 min of onset.
The simultaneous ring system was reliable and effective, permitting enrollment of a substantial number of patients within the first hour after stroke onset. VOIP cellular networks with simultaneous ring are a preferred means of facilitating consent in prehospital treatment trials.
[Show abstract][Hide abstract] ABSTRACT: Endovascular recanalization therapies are an increasingly employed treatment strategy in acute cerebral ischemia. The determinants of the final clinical outcome after endovascular treatment have been understudied. We investigated the effects of hyperlipidemia and statins on acute ischemic stroke outcomes after endovascular procedures.
An inquiry of a prospectively maintained stroke registry was conducted. Endovascular procedures were performed using recombinant tissue plasminogen activator, prourokinase or the Merci device within 12 hours after symptom onset. The analyzed outcomes were revascularization, hemorrhage and excellent functional outcome (Rankin score of 0-1 at 3 months). The analyses included chi(2) and Wilcoxon rank sum, logistic regression (for multivariate analyses with binary outcomes) and linear regression (for continuous outcomes). Significance was set at p < 0.05.
We included 142 patients, 80% treated with intra-arterial fibrinolysis, 22% with percutaneous mechanical embolectomy and 27% treated with intravenous fibrinolysis prior to endovascular intervention. Age (OR = 0.956, 95% CI = 0.927-0.986, p = 0.0041), National Institutes of Health Stroke Scale (NIHSS) score on admission (OR = 0.881, 95% CI = 0.812-0.957, p = 0.0025) and history of hyperlipidemia (OR = 0.284, 95% CI = 0.08-0.99, p = 0.0478) were negatively associated with excellent functional outcome at 3 months. Every 50 mg/dl increment in the total cholesterol level resulted in 64% decrease in the odds of excellent functional outcome (OR = 0.36, 95% CI = 0.447-0.882, p = 0.0253). History of hyperlipidemia decreased the likelihood of neurological improvement (p = 0.0462) and was associated with a higher NIHSS score at 7 days or discharge. Statin use was related to an average 6.5-unit NIHSS decrease at discharge (p = 0.0168). Statins were not associated with increased frequency of recanalization or symptomatic intracerebral hemorrhage.
History of hyperlipidemia may have a negative impact on the outcomes of acute ischemic stroke treated with intra-arterial fibrinolysis or percutaneous mechanical embolectomy. Statin use before and after these procedures may be related to better neurological outcomes. Larger prospective studies are needed to endorse these findings.
[Show abstract][Hide abstract] ABSTRACT: Although stroke from large vessel atherothromboembolism has a common pathogenesis, its topographic presentation is variable. Given the impact of cerebral infarct size and location on incident stroke magnitude and subsequent prognosis, we evaluated the determinants of cerebral infarct topography among patients with atherosclerotic stroke.
We analyzed data on 148 consecutive patients admitted over a 4-year period to a university medical center with acute ischemic stroke within the MCA distribution on DWI, presumed due to atherosclerosis. Based on the DWI data, we divided the patients into three stroke phenotypes: large cortical, small (< 1 cm in diameter) cortical, and deep pattern. Independent factors for each stroke phenotype were evaluated using logistic regression.
After adjusting for covariates, premorbid statin use (OR, 3.05; 95% CI, 1.40-6.65) and older age (OR, 1.05 per 1 year increase; 95% CI, 1.02-1.08) were independently associated with the small cortical phenotypic pattern. In contrast, younger age (OR, 0.95 per 1 year increase; 95% CI, 0.92-0.98), premorbid statin non-use (OR, 0.40; 95% CI, 0.17-0.99), and higher levels of fasting s-glucose (OR, 1.01 per 1 mg/dl increase; 95% CI, 1.00-1.02) and admission peripheral WBC counts (OR, 1.13 per 1 x 10(9) cells/L; 95% CI, 1.00-1.27) were independently associated with the large cortical pattern. There was no relation between DWI patterns and LDL-cholesterol levels.
Age, premorbid statin use, s-glucose and WBC count predict atherosclerotic stroke phenotype. Further studies should examine whether modifying some of these factors may result in more favorable phenotypic patterns.
Journal of Neurology 05/2009; 256(4):591-9. DOI:10.1007/s00415-009-0125-x · 3.38 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Prestroke statin use may improve ischemic stroke outcomes, yet there is also evidence that statins and extremely low cholesterol levels may increase the risk of intracranial hemorrhage. We evaluated the independent effect of statin use and admission cholesterol level on risk of symptomatic hemorrhagic transformation (sHT) after recanalization therapy for acute ischemic stroke.
We analyzed ischemic stroke patients recorded in a prospectively maintained registry that received recanalization therapies (IV or intra-arterial fibrinolysis or endovascular embolectomy) at a university medical center from September 2002 to May 2006. The independent effect of premorbid statin use on sHT post intervention was evaluated by logistic regression, adjusting for prognostic and treatment variables known to predict increased HT risk after ischemic stroke.
Among 104 patients, mean age was 70 years, and 49% were men. Male sex, hypertension, statin use, low total cholesterol and low-density lipoprotein (LDL) cholesterol, current smoking, elevated glucose levels, and higher admission NIH Stroke Scale (NIHSS) score were all associated with a greater risk of sHT in univariate analysis. After adjusting for covariates, low LDL cholesterol (odds ratio [OR], 0.968 per 1-mg/dL increase; 95% CI, 0.941 to 0.995), current smoking (OR, 14.568; 95% CI, 1.590 to 133.493), and higher NIHSS score (OR, 1.265 per 1-point increase; 95% CI, 1.047 to 1.529) were independently associated with sHT risk.
Lower admission low-density lipoprotein cholesterol level with or without statin use, current smoking, and greater stroke severity are associated with greater risk for symptomatic hemorrhagic transformation after recanalization therapy for ischemic stroke.
[Show abstract][Hide abstract] ABSTRACT: Hunter syndrome, or mucopolysaccharidosis type II, is an X-linked recessive disorder resulting from iduronate sulfatase deficiency. Typical manifestations include short stature, mental retardation, hydrocephalus, macroglossia and cardiac valvulopathy. We describe a 21-year-old patient who presented with acute ischemic stroke and evidence of cerebral embolization. The echocardiogram demonstrated thickened mitral and aortic valves as potential sources of emboli. We conclude that ischemic stroke secondary to cardioembolization is a potential complication of Hunter syndrome.
[Show abstract][Hide abstract] ABSTRACT: Abnormalities in diffusion-weighted (DWI) and perfusion-weighted (PWI) magnetic resonance imaging (MRI) are thought to reflect the presence of brain tissue at risk for ischemic stroke. Many patients with acute ischemic stroke have a mismatch pattern in which the PWI volume is larger than the DWI lesion. This mismatch typically resolves over 24-48 hours. Little is known about the presence of DWI-PWI mismatch in later stages of stroke.
This is a retrospective study of 122 patients admitted with a diagnosis of acute ischemic stroke who had DWI and PWI abnormalities on studies performed within 7 days of onset of symptoms. Patients were divided into two groups: those with MRI performed <48 hours and those with MRI performed >or=48 hours from onset of symptoms.
Among 42 patients with MRI performed >or=48 hours after onset of stroke symptoms, 15 of 42 (36%) showed a mismatch pattern, compared to 45 of 80 (56%) in the <48 hours group (P < 0.05). Most of the patients in the >or=48 hours group with mismatch had large artery occlusive disease and many had neurological fluctuations. A subset of these patients were treated with induced hypertension and showed clinical improvement.
Some patients have persistent DWI-PWI mismatch up to several days after stroke onset. Further studies are needed to determine if these patients should be candidates for reperfusion therapy.
Journal of Neuroimaging 11/2006; 16(4):329-33. DOI:10.1111/j.1552-6569.2006.00063.x · 1.73 Impact Factor