Lucas Restrepo

Barrow Neurological Institute, Phoenix, AZ, United States

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Publications (26)55.25 Total impact

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    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;
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    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. Methods: 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. Results: 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. Conclusions: 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.
    The Neurohospitalist. 07/2012; 2(3):82-6.
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    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;
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    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.
    Cerebrovascular Diseases 10/2009; 28(6):539-44. · 2.81 Impact Factor
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    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.
    Cerebrovascular Diseases 09/2009; 28(4):384-90. · 2.81 Impact Factor
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    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. · 3.58 Impact Factor
  • LUCAS RESTREPO, MICHAEL A. JACOBS
    01/2009;
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    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.
    Neurology 04/2007; 68(10):737-42. · 8.30 Impact Factor
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    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.
    Journal of Clinical Neuroscience 01/2007; 13(10):1054-7. · 1.25 Impact Factor
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    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. · 1.41 Impact Factor
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    ABSTRACT: The management of blood pressure in acute stroke is controversial. Small pilot studies have suggested that blood pressure augmentation improves short-term neurological function, but the rate of adverse events with induced hypertension (IH) therapy is unknown. We reviewed 100 consecutive patients who underwent perfusion magnetic resonance imaging for acute ischemic stroke. IH therapy was employed in 46 patients and standard therapy (ST) in 54. The two groups had similar baseline characteristics, but more patients in the IH group had significant large-artery stenoses. The IH group achieved significantly higher mean arterial pressure (MAP) than the ST group within 3 days of initiation of therapy with a variety of vasopressor agents. Only 35% of patients in the IH group actually achieved the target MAP augmentation of 10-20% above baseline, however. All patients survived to discharge. Four patients experienced major adverse events in each group. Two patients in the IH group experienced intra cerebral hemorrhage compared to none in the ST group. Two patients in the ST group experienced myocardial ischemia, compared to none in the IH group. The National Institutes of Health Stroke Scale during the hospitalization and place of discharge were similar in both groups. Patients in the IH group were more likely to be admitted to the intensive care unit and had a longer hospital stay by nearly 4 days compared to the ST group. These data demonstrate the relative safety of IH therapy in acute stroke patients. Given the greater use of resources, however, the role of IH in improving clinical outcomes requires a prospective, randomized trial.
    Neurocritical Care 02/2006; 4(1):3-7. · 3.04 Impact Factor
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    Lucas Restrepo, Jorge F Guttin
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    ABSTRACT: Acute anterior spinal cord ischemia is a rare but disastrous complication of endovascular aortic procedures. Although intravenous thrombolysis with recombinant tissue plasminogen activator is an effective treatment for acute brain ischemia, its use for the treatment of spinal cord ischemia has not previously been reported. We report the case of a patient who developed anterior spinal cord ischemia during diagnostic aortography He was treated with intravenous recombinant tissue plasminogen activator within 3 hours after the onset of symptoms. The patient had a rapid neurologic improvement and was discharged from the hospital 3 days after thrombolysis, regaining his ability to walk unassisted. We propose that acute spinal cord ischemia can be treated with intravenous recombinant tissue plasminogen activator within 3 hours after the onset of symptoms, as can any other case of acute ischemic stroke.
    Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital 02/2006; 33(1):74-7. · 0.67 Impact Factor
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    ABSTRACT: Diffusion-and perfusion-weighted magnetic resonance imaging (DWI and PWI) are useful tools for the assessment of brain ischemia. Discrepancies between the extent of DWI and PWI abnormalities are thought to depend pre dominantly on time from symptom onset to magnetic resonance imaging (MRI) examination. However, underlying ischemic stroke etiology can also be important. A mismatch may indicate the presence of tissue at risk for infarction, whereas the relevance of other DWI/PWI patterns is uncertain. The authors therefore investigated the etiology of brain ischemia in patients with different DWI/PWI patterns. Retrospective study of 130 patients with acute brain ischemia and detailed stroke workup, including MRI within a week after symptom onset (40 +/- 39 hours). Patients were divided into the following groups: mis-match (PWI > DWI), reverse mismatch (DWI > PWI), and match (<25% difference between PWI and DWI). Mismatch occurred in 49% of patients, whereas 22% had reverse mis-match and 29% matched lesions. Time from symptom onset to MRI examination was similar between the 3 groups. Largeartery atherosclerosis increased by almost 4-fold the odds of mismatch (odds ratio: 3.89, 95% confidence interval: 1.72-8.78; P < .001), whereas patients with reverse mismatch were likely to have cryptogenic stroke. Patients with matched lesions were similarly distributed among different stroke subtypes. Ischemic stroke etiology appears to influence the development of specific DWI/PWI patterns. Prospective studies are needed to confirm these observations.
    Journal of Neuroimaging 07/2005; 15(3):254-60. · 1.41 Impact Factor
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    ABSTRACT: The so-called rubral tremor is a clinical diagnosis that involves involuntary shaking limb movements during rest and voluntary motion. We report the cases of 2 patients who developed rubral tremor after cardiac catheterization. To our knowledge, this is the 1st report of such an association. In each case, brain magnetic resonance imaging revealed nothing unusual. The onset of tremor after cardiac catheterization may signal the presence of a complex neurologic syndrome, which warrants consultation with a neurologist.
    Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital 02/2005; 32(3):427-9. · 0.67 Impact Factor
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    ABSTRACT: A variety of fluent and nonfluent aphasias have been reported after left basal ganglia stroke. It has been speculated that this heterogeneity may reflect variations in cortical hypoperfusion resulting from large vessel stenosis. To test this hypothesis, a consecutive series of 24 patients with left caudate infarct identified with diffusion-weighted imaging underwent language testing and perfusion-weighted imaging < 24h from onset of symptoms. Specific regions in perisylvian cortex were rated for the percentage of the region that was hypoperfused. Aphasia type was determined on the basis of speech fluency, comprehension, and repetition performance on the language tests. Association between aphasia type/language impairment and regions of hypoperfusion were identified with Fisher's exact tests. Results demonstrated that in patients with acute left caudate infarct, the presence and type of aphasia reflected regions of hypoperfusion, and generally followed predictions based on chronic lesion studies, regarding anatomical lesions associated with classic aphasia types.
    Brain and Language 07/2004; 89(3):524-30. · 3.39 Impact Factor
  • Dawn E. Jaroszewski, Lucas Restrepo
    Seminars in Cerebrovascular Diseases and Stroke 06/2004; 4(2):126–128.
  • Dawn E. Jaroszewski, Lucas Restrepo
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    ABSTRACT: Coronary artery bypass graft surgery (CABG) is one of the most commonly performed major surgical procedures. However, patients having undergone CABG may experience neurological problems such as stroke, delirium, and cognitive difficulties. Observations suggest that these complications are caused by several synergistic factors, most prominently brain ischemia secondary to cerebral hypoperfusion and/or embolization of heterogeneous endovascular debris. Embolic signals are commonly detected during surgery using intraoperative transcranial Doppler monitoring. After surgery, magnetic resonance imaging of the brain may detect scattered areas of brain ischemia in patients with or without delirium. The large majority of these patients do not exhibit focal neurological deficits suggestive of ischemic stroke. We review the literature pertaining to postoperative encephalopathy, with emphasis on prevention, diagnosis, and treatment.
    Seminars in Cerebrovascular Diseases and Stroke. 01/2004;
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    ABSTRACT: Management of arterial dissections can be particularly challenging. We report a case of vertebral artery dissection in which perfusion- and diffusion-weighted MR imaging findings suggested the presence of salvageable tissue, despite that the patient had symptoms for more than 40 hours. Direct access to the distal vascular territory was unattainable, and the presence of collateral circulation through an occipital vertebral anastomosis provided the only pathway to administer intraarterial thrombolysis. This case demonstrates that perfusion- and diffusion-weighted MR imaging can be instrumental in the selection of candidates for aggressive stroke therapy. Arterial anastomoses can provide alternate access to ischemic vascular beds and merit careful evaluation during intraarterial thrombolysis.
    American Journal of Neuroradiology 11/2003; 24(9):1823-6. · 3.17 Impact Factor
  • Robert J. Wityk, Lucas Restrepo
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    ABSTRACT: Control of hypertension is a well-established goal of the primary and secondary prevention of stroke. However, management of blood pressure in the setting of acute brain ischemia is complicated by the possible effect of blood pressure changes on cerebral perfusion. In acute stroke, patients may have an ischemic penumbra of brain tissue, which has impaired perfusion but which is not irreversibly damaged. The ischemic penumbra may be salvaged with reperfusion. Lowering of blood pressure in this setting, however, would hasten the progression of the penumbra to infarction. With the exception of patients treated with thrombolytic agents, blood pressure reduction is not recommended in acute ischemic stroke for this reason. Preliminary studies suggest that there may be a role for interventions to elevate blood pressure as a treatment for acute stroke patients. Despite interest in induced hypertension as a treatment of stroke dating back to the 1950s, this practice has not achieved widespread use owing to concerns about potential adverse effects such as intracerebral hemorrhage, cerebral edema, and myocardial ischemia. It is commonly used, however, to treat patients with threatened cerebral ischemia due to vasospasm after subarachnoid hemorrhage. Until future studies clarify the effectiveness of induced hypertension in stroke treatment, maintaining adequate blood pressure and fluid volume is recommended for patients with acute ischemic stroke, particularly if the neurologic deficits are fluctuating or the patient has persistent large-vessel occlusive disease.
    Current Treatment Options in Cardiovascular Medicine 08/2003; 5(3):193-199.
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    ABSTRACT: During the evaluation of acute ischemic stroke with diffusion- and perfusion-weighted magnetic resonance imaging (DWI and PWI, respectively), the presence of salvageable brain tissue is suggested by the occurrence of a perfusion-diffusion "mismatch." DWI and PWI, however, are not universally available and have inherent inconveniences, which justify a search for practical diagnostic alternatives. The purpose of this study is to investigate whether there are transcranial Doppler (TCD) markers of mismatch. Retrospective analysis of 22 patients with acute ischemic stroke affecting the middle cerebral artery (MCA) territory, who had a TCD performed within 24 hours of magnetic resonance imaging (MRI) with DWI and PWI. MRI and TCD were performed on average 10.8 +/- 9.2 hours apart. Time from symptom onset to MRI and TCD completion were 1.6 +/- 1.6 and 2 +/- 1.9 days, respectively. MCA and intracranial internal carotid artery (ICA) cerebral blood flow velocity (CBFV) asymmetry, together with a large ICA-to-MCA gradient, were associated with the presence of mismatch. The combined use of 2 TCD parameters (MCA CBFV asymmetry of > or = 30% and ICA-to-MCA gradient > or = 20 cm/sec) had a sensitivity of 75%, specificity of 80%, positive predictive value of 82%, and negative predictive value of 73% at detecting mismatch cases. Diffusion-perfusion mismatch appears to be associated with interhemispheric asymmetry between MCA and ICA CBFVs, and a large CBFV gradient between the ICA and MCA on the affected side. Prospective studies are required to verify these observations and to determine whether TCD can be used to follow patients with mismatch.
    Journal of Neuroimaging 01/2003; 13(1):34-42. · 1.41 Impact Factor

Publication Stats

336 Citations
55.25 Total Impact Points

Institutions

  • 2011–2013
    • Barrow Neurological Institute
      • Department of Neurology
      Phoenix, AZ, United States
  • 2006–2011
    • University of California, Los Angeles
      • Department of Neurology
      Los Angeles, California, United States
  • 2009
    • Harbor-UCLA Medical Center
      Torrance, California, United States
    • University of Southern California
      • Department of Neurology
      Los Angeles, CA, United States
    • Samsung Medical Center
      • Department of Neurology
      Seoul, Seoul, South Korea
  • 2007
    • University of California, San Francisco
      • Department of Neurology
      San Francisco, CA, United States
  • 2003–2006
    • Johns Hopkins Medicine
      • Department of Neurology
      Baltimore, Maryland, United States
    • Johns Hopkins University
      • Department of Neurology
      Baltimore, MD, United States
  • 2004
    • University of Texas Medical School
      Houston, Texas, United States
    • Baylor College of Medicine
      Houston, Texas, United States
    • St. Luke School of Medicine
      Houston, Texas, United States