472 results on '"Warach S"'
Search Results
2. Prevalence, Trajectory, and Predictors of Poststroke Pain: Retrospective Analysis of Pooled Clinical Trial Data Set
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Ali, Myzoon, Tibble, Holly, Brady, Marian C., Quinn, Terence J., Sunnerhagen, Katharina S., Venketasubramanian, Narayanaswamy, Shuaib, Ashfaq, Pandyan, Anand, Mead, Gillian, Lees, K.R., Alexandrov, A., Bath, P.M., Bluhmki, E., Bornstein, N., Chen, C., Claesson, L., Curram, J., Davis, S.M., Diener, H-C., Donnan, G., Fisher, M., Ginsberg, M., Gregson, B., Grotta, J., Hacke, W., Hennerici, M.G., Hommel, M., Kaste (Emeritus), M., Lyden, P., Marler, J., Muir, K., Roffe, C., Teal, P., Wahlgren, N.G., Warach, S., Ali, M., Ashburn, A., Barer, D., Barzel, A., Bernhardt, J., Bowen, A., Drummond, A., Edmans, J., English, C., Gladman (Emeritus), J., Godecke, E., Hiekkala, S., Hoffman, T., Kalra, L., Kuys, S., Langhorne, P., Laska, A.C., Lees, K.R., Logan, P., Machner, B., Morris, J., Pollock, A., Pomeroy, V., Rodgers, H., Sackley, C., Shaw, L., Stott, D.J., Tyson, S., van Vliet, P., Walker, M., Whiteley, W., Hanley, D.F., Butcher, K., Davis, S., Gregson, B., Lees, K.R., Lyden, P., Mayer, S., Muir, K., and Steiner, T.
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- 2023
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3. The Role of Stroke MRI in Clinical Trials
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Warach, S., Schellinger, P. D., Fiebach, Jochen B., Schellinger, Peter D., Sartor, Klaus, Heiland, Sabine, Warach, Steven, and Hacke, Werner
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- 2003
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4. Impact of Stroke MRI on Therapeutic Decision Making
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Schellinger, P. D., Fiebach, J. B., Warach, S., Hacke, W., Fiebach, Jochen B., Schellinger, Peter D., Sartor, Klaus, Heiland, Sabine, Warach, Steven, and Hacke, Werner
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- 2003
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5. Characterization of Hyperacute Ischemic Stroke with Stroke MM
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Schellinger, P. D., Fiebach, J. B., Warach, S., Fiebach, Jochen B., Schellinger, Peter D., Sartor, Klaus, Heiland, Sabine, Warach, Steven, and Hacke, Werner
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- 2003
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6. Sex and Stroke in Thrombolyzed Patients and Controls
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Hametner, Christian, MacIsaac, Rachael L., Kellert, Lars, Abdul-Rahim, Azmil H., Ringleb, Peter A., Lees, Kennedy R., Alexandrov, A., Bath, P.M., Bluhmki, E., Bornstein, N., Chen, C., Claesson, L., Davis, S.M., Donnan, G., Diener, H.C., Fisher, M., Ginsberg, M., Gregson, B., Grotta, J., Hacke, W., Hennerici, M.G., Hommel, M., Kaste, M., Lyden, P., Marler, J., Muir, K., Venketasubramanian, N., Sacco, R., Shuaib, A., Teal, P., Wahlgren, N.G., Warach, S., and Weimar, C.
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- 2017
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7. Clinical Applications of Neuroimaging Using Echo-Planar Imaging
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Siewert, B., Warach, S., Schmitt, Franz, Stehling, Michael K., and Turner, Robert
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- 1998
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8. New MR Technologies for Diagnosis of Acute Ischemic Stroke: MR Angiography, Diffusion, and Perfusion Imaging
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Warach, S., Yamaguchi, Takenori, editor, Mori, Etsuro, editor, Minematsu, Kazuo, editor, and del Zoppo, Gregory J., editor
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- 1995
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9. Temporal Profile of Pneumonia After Stroke
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de Jonge, Jeroen C., primary, van de Beek, Diederik, additional, Lyden, Patrick, additional, Brady, Marian C., additional, Bath, Philip M., additional, van der Worp, H. Bart, additional, Lees, K.R., additional, Alexandrov, A., additional, Berge, E., additional, Bluhmki, E., additional, Bornstein, N., additional, Chen, C., additional, Claesson, L., additional, Davis, S.M., additional, Donnan, G., additional, Diener, H.C., additional, Fisher, M., additional, Ginsberg, M., additional, Gregson, B., additional, Grotta, J., additional, Hacke, W., additional, Hennerici, M.G., additional, Hommel, M., additional, Kaste, M., additional, Marler, J., additional, Muir, K., additional, Venketasubramanian, N., additional, Sacco, R., additional, Shuaib, A., additional, Teal, P., additional, Wahlgren, N.G., additional, Warach, S., additional, and Weimar, C., additional
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- 2022
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10. How Well Do Standard Stroke Outcome Measures Reflect Quality of Life?: A Retrospective Analysis of Clinical Trial Data
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Ali, Myzoon, Fulton, Rachael, Quinn, Terry, Brady, Marian, Lees, K. R., Alexandrov, A., Bath, P. M., Bluhmki, E., Bornstein, N., Claesson, L., Davis, S. M., Donnan, G., Diener, H. C., Fisher, M., Gregson, B., Grotta, J., Hacke, W., Hennerici, M. G., Hommel, M., Kaste, M., Lyden, P., Marler, J., Muir, K., Sacco, R., Shuaib, A., Teal, P., Wahlgren, N. G., Warach, S., Weimar, C., Brady, M., Ali, M., Ashburn, A., Barer, D., Bernhardt, J., Bowen, A., Brodie, E., Corr, S., Drummond, A., Edmans, J., English, C., Gladman, J., Godecke, E., Hoffmann, T., Kalra, L., Kuys, S., Langhorne, P., Laska, A. C., Lees, K. R., Lincoln, N., Logan, P., Jongbloed, L., Mead, G., Pollock, A., Pomeroy, V., Rodgers, H., Sackley, C., Shaw, L., Stott, D. J., Sunnerhagen, K. S., Tyson, S., van Vliet, P., Walker, M., Whiteley, W., Warach, S., Albers, G., Davis, S., Donnan, G., Fisher, M., Furlan, T., Grotta, J., Hacke, W., Kidwell, C., Koroshetz, W., Lees, K. R., Lev, M., Liebeskind, D., Sorensen, G., Thijs, V., Thomalla, G., Wardlaw, J., Wintermark, M., Hanley, D. F., Gregson, B., Davis, S., Lees, K. R., Lyden, P., Muir, K., Steiner, T., Mayer, S., Wahlgren, N. G., Molina, C., Numminen, H., Lees, K. R., Tsivgoulis, G., Weimar, C., Diener, H. -C., Hankey, G., Lees, K. R., Ovbiagele, B., and Weir, C.
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- 2013
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11. β-Blockers, Pneumonia, and Outcome After Ischemic Stroke: Evidence From Virtual International Stroke Trials Archive
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Sykora, Marek, Siarnik, Pavel, Diedler, Jennifer, Lees, K.R., Alexandrov, A., Bath, P.M., Bluhmki, E., Bornstein, N., Claesson, L., Davis, S.M., Donnan, G., Diener, H. C., Fisher, M., Ginsberg, M., Gregson, B., Grotta, J., Hacke, W., Hennerici, M.G., Hommel, M., Kaste, M., Lyden, P., Marler, J., Muir, K., Sacco, R., Shuaib, A., Teal, P., Wahlgren, N.G., Warach, S., and Weimar, C.
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- 2015
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12. National Institutes of Health Stroke Scale Item Profiles as Predictor of Patient Outcome: External Validation on Independent Trial Data
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Abdul-Rahim, Azmil H., Fulton, Rachael L., Sucharew, Heidi, Kleindorfer, Dawn, Khatri, Pooja, Broderick, Joseph P., Lees, Kennedy R., Alexandrov, A., Bath, P.M., Bluhmki, E., Bornstein, N., Claesson, L., Curram, J., Davis, S.M., Donnan, G., Diener, H.C., Fisher, M., Ginsberg, M., Gregson, B., Grotta, J., Hacke, W., Hennerici, M.G., Hommel, M., Kaste, M., Lyden, P., Marler, J., Muir, K., Sacco, R., Shuaib, A., Teal, P., Wahlgren, N.G., Warach, S., and Weimar, C.
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- 2015
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13. Associations of chronic heart failure with outcome in acute ischaemic stroke patients who received systemic thrombolysis: analysis from VISTA
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Abdul-Rahim, A. H., Fulton, R. L., Frank, B., McMurray, J. J. V., Lees, K. R., Alexandrov, A. V., Bath, P. W., Bluhmki, E., Claesson, L., Curram, J., Davis, S. M., Donnan, G., Diener, H. C., Fisher, M., Gregson, B., Grotta, J., Hacke, W., Hennerici, M. G., Hommel, M., Kaste, M., Lyden, P., Marler, J., Muir, K., Sacco, R., Shuaib, A., Teal, P., Wahlgren, N. G., Warach, S., and Weimar, C.
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- 2015
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14. O-010 Racial disparity in mechanical thrombectomy utilization: multicenter registry results from 2016–2020
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Wallace, A, primary, Gibson, D, additional, Asif, K, additional, Sahlein, D, additional, Warach, S, additional, Malisch, T, additional, and Lamonte, M, additional
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- 2021
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15. Characteristic Adverse Events and Their Incidence Among Patients Participating in Acute Ischemic Stroke Trials
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Hesse, Kerrick, Fulton, Rachael L., Abdul-Rahim, Azmil H., Lees, Kennedy R., Alexandrov, A.V., Bath, P.W., Bluhmki, E., Claesson, L., Curram, J., Davis, S.M., Donnan, G., Diener, H.C., Fisher, M., Gregson, B., Grotta, J., Hacke, W., Hennerici, M.G., Hommel, M., Kaste, M., Lyden, P., Marler, J., Muir, K., Sacco, R., Shuaib, A., Teal, P., Wahlgren, N.G., Warach, S., and Weimar, C.
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- 2014
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16. THRIVE Score Predicts Ischemic Stroke Outcomes and Thrombolytic Hemorrhage Risk in VISTA
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Flint, Alexander C., Faigeles, Bonnie S., Cullen, Sean P., Kamel, Hooman, Rao, Vivek A., Gupta, Rishi, Smith, Wade S., Bath, Philip M., Donnan, Geoffrey A., Lees, K.R., Alexandrov, A., Bath, P.M., Bluhmki, E., Bornstein, N., Claesson, L., Davis, S.M., Donnan, G., Diener, H.C., Fisher, M., Gregson, B., Grotta, J., Hacke, W., Hennerici, M.G., Hommel, M., Kaste, M., Lyden, P., Marler, J., Muir, K., Sacco, R., Shuaib, A., Teal, P., Wahlgren, N.G., Warach, S., and Weimar, C.
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- 2013
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17. Does the cognitive measure Cog-4 show improvement among patients treated with thrombolysis after acute stroke?
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Hajjar, Karim, Fulton, Rachael L., Diener, Hans-Christoph, Lees, Kennedy R., Alexandrov, A, Bath, PMW, Bluhmki, E, Claesson, L, Curram, J, Davis, SM, Donnan, G, Diener, HC, Fisher, M, Gregson, B, Grotta, J, Hacke, W, Hennerici, MG, Hommel, M, Kaste, M, Lees, KR, Lyden, P, Marler, J, Muir, K, Sacco, R, Shuaib, A, Teal, P, Wahlgren, NG, Warach, S, and Weimar, C
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- 2013
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18. Intravenous alteplase for unknown time of onset stroke guided by advanced imaging: a systematic review and meta-analysis of individual patient data
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Thomalla, G., Boutitie, F., Ma, H., Koga, M., Ringleb, P., Schwamm, L.H., Wu, O., Bendszus, M., Bladin, C.F., Campbell, B.C.V., Cheng, B., Churilov, L., Ebinger, M., Endres, M., Fiebach, J.B., Fukuda-Doi, M., Inoue, M., Kleinig, T.J., Latour, L.L., Lemmens, R., Levi, C.R., Leys, D., Miwa, K., Molina, C., Muir, K.W., Nighoghossian, N., Parsons, M.W., Pedraza, S., Schellinger, P., Schwab, S., Simonsen, C.Z., Song, S.S., Thijs, V., Toni, D., Hsu, C., Wahlgren, N., Yamamoto, H., Yassi, N., Yoshimura, S., Warach, S., Hacke, W., Toyoda, K., Donnan, G.A., Davis, S.M., and Gerloff, C.
- Abstract
Background: \ud Patients who have had a stroke with unknown time of onset have been previously excluded from thrombolysis. We aimed to establish whether intravenous alteplase is safe and effective in such patients when salvageable tissue has been identified with imaging biomarkers.\ud \ud Methods: \ud We did a systematic review and meta-analysis of individual patient data for trials published before Sept 21, 2020. Randomised trials of intravenous alteplase versus standard of care or placebo in adults with stroke with unknown time of onset with perfusion-diffusion MRI, perfusion CT, or MRI with diffusion weighted imaging-fluid attenuated inversion recovery (DWI-FLAIR) mismatch were eligible. The primary outcome was favourable functional outcome (score of 0–1 on the modified Rankin Scale [mRS]) at 90 days indicating no disability using an unconditional mixed-effect logistic-regression model fitted to estimate the treatment effect. Secondary outcomes were mRS shift towards a better functional outcome and independent outcome (mRS 0–2) at 90 days. Safety outcomes included death, severe disability or death (mRS score 4–6), and symptomatic intracranial haemorrhage. This study is registered with PROSPERO, CRD42020166903.\ud \ud Findings: \ud Of 249 identified abstracts, four trials met our eligibility criteria for inclusion: WAKE-UP, EXTEND, THAWS, and ECASS-4. The four trials provided individual patient data for 843 individuals, of whom 429 (51%) were assigned to alteplase and 414 (49%) to placebo or standard care. A favourable outcome occurred in 199 (47%) of 420 patients with alteplase and in 160 (39%) of 409 patients among controls (adjusted odds ratio [OR] 1·49 [95% CI 1·10–2·03]; p=0·011), with low heterogeneity across studies (I2=27%). Alteplase was associated with a significant shift towards better functional outcome (adjusted common OR 1·38 [95% CI 1·05–1·80]; p=0·019), and a higher odds of independent outcome (adjusted OR 1·50 [1·06–2·12]; p=0·022). In the alteplase group, 90 (21%) patients were severely disabled or died (mRS score 4–6), compared with 102 (25%) patients in the control group (adjusted OR 0·76 [0·52–1·11]; p=0·15). 27 (6%) patients died in the alteplase group and 14 (3%) patients died among controls (adjusted OR 2·06 [1·03–4·09]; p=0·040). The prevalence of symptomatic intracranial haemorrhage was higher in the alteplase group than among controls (11 [3%] vs two [
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- 2020
19. Diffusionsgewichtete Bildgebung beim akuten Hirnschlag
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Jakob, P. M., Lövblad, K.-O., Weber, J., Laubach, H.-J., Remonda, L., Gönner, F., Heid, O., Mattle, H. P., Schroth, G., Edelman, R. R., and Warach, S.
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- 1998
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20. Antibiotic Class and Outcome in Post-stroke Infections: An individual participant data pooled analysis of VISTA-acute
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Smith, Craig J., Heal, Calvin, Vail, Andy, Jeans, Adam R., Westendorp, Willeke F., Nederkoorn, Paul J., van de Beek, Diederik, Kalra, Lalit, Montaner, Joan, Woodhead, Mark, Meisel, Andreas, Lees, K. R., Alexandrov, A., Bath, P. M., Berge, E., Bluhmki, E., Bornstein, N., Chen, C., Claesson, L., Davis, S. M., Donnan, G., Diener, H. C., Fisher, M., Ginsberg, M., Gregson, B., Grotta, J., Hacke, W., Hennerici, M. G., Hommel, M., Kaste, M., Lyden, P., Marler, J., Muir, K., Venketasubramanian, N., Sacco, R., Shuaib, A., Teal, P., Wahlgren, N. G., Warach, S., Weimar, C., Graduate School, ACS - Atherosclerosis & ischemic syndromes, AII - Infectious diseases, ANS - Neurovascular Disorders, and Neurology
- Abstract
Introduction: Antibiotics used to treat post-stroke infections have differing antimicrobial and anti-inflammatory effects. Our aim was to investigate whether antibiotic class was associated with outcome after post-stroke infection. Methods: We analyzed pooled individual participant data from the Virtual International Stroke Trials Archive (VISTA)-Acute. Patients with ischemic stroke and with an infection treated with systemic antibiotic therapy during the first 2 weeks after stroke onset were eligible. Antibiotics were grouped into eight classes, according to antimicrobial mechanism and prevalence. The primary analysis investigated whether antibiotic class for any infection, or for pneumonia, was independently associated with a shift in 90 day modified Rankin Scale (mRS) using ordinal logistic regression. Results: 2,708 patients were eligible (median age [IQR] = 74 [65 to 80] y; 51% female; median [IQR] NIHSS score = 15 [11 to 19]). Pneumonia occurred in 35%. Treatment with macrolides (5% of any infections; 9% of pneumonias) was independently associated with more favorable mRS distribution for any infection [OR (95% CI) = 0.59 (0.42 to 0.83), p = 0.004] and for pneumonia [OR (95% CI) = 0.46 (0.29 to 0.73), p = 0.001]. Unfavorable mRS distribution was independently associated with treatment of any infection either with carbapenems, cephalosporins or monobactams [OR (95% CI) = 1.62 (1.33 to 1.97), p < 0.001], penicillin plus β-lactamase inhibitors [OR (95% CI) = 1.26 (1.03 to 1.54), p = 0.025] or with aminoglycosides [OR (95% CI) = 1.73 (1.22 to 2.46), p = 0.002]. Conclusion: This retrospective study has several limitations including effect modification and confounding by indication. Macrolides may have favorable immune-modulatory effects in stroke-associated infections. Prospective evaluation of the impact of antibiotic class on treatment of post-stroke infections is warranted.
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- 2019
21. Timing of anticoagulation after recent ischaemic stroke in patients with atrial fibrillation
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Seiffge, D. J., Werring, D. J., Paciaroni, M., Dawson, J., Warach, S., Milling, T. J., Engelter, S. T., Fischer, Urs, and Norrving, B.
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cardiovascular diseases ,610 Medicine & health - Abstract
BACKGROUND: About 13-26 of all acute ischaemic strokes are related to non-valvular atrial fibrillation, the most common cardiac arrhythmia globally. Deciding when to initiate oral anticoagulation in patients with non-valvular atrial fibrillation is a longstanding, common, and unresolved clinical challenge. Although the risk of early recurrent ischaemic stroke is high in this population, early oral anticoagulation is suspected to increase the risk of potentially harmful intracranial haemorrhage, including haemorrhagic transformation of the infarct. This assumption, and current treatment guidelines, are based on historical, mostly observational data from patients with ischaemic stroke and atrial fibrillation treated with heparins, heparinoids, or vitamin K antagonists (VKAs) to prevent recurrent ischaemic stroke. Randomised controlled trials have subsequently shown that direct oral anticoagulants (DOACs; ie, apixaban, dabigatran, edoxaban, and rivaroxaban) are at least as effective as VKAs in primary and secondary prevention of atrial fibrillation-related ischaemic stroke, with around half the risk of intracranial haemorrhage. However, none of these DOAC trials included patients who had experienced ischaemic stroke recently (within the first few weeks). Clinicians therefore remain uncertain regarding when to commence DOAC administration after acute ischaemic stroke in patients with atrial fibrillation. RECENT DEVELOPMENTS: Prospective observational studies and two small randomised trials have investigated the risks and benefits of early DOAC-administration initiation (most with a median delay of 3-5 days) in mild-to-moderate atrial fibrillation-associated ischaemic stroke. These studies reported that early DOAC treatment was associated with a low frequency of clinically symptomatic intracranial haemorrhage or surrogate haemorrhagic lesions on MRI scans, whereas later DOAC-administration initiation (ie, >7 days or >14 days after index stroke) was associated with an increased frequency of recurrent ischaemic stroke. WHERE NEXT?: Adequately powered randomised controlled trials comparing early to later oral anticoagulation with DOACs in ischaemic stroke associated with atrial fibrillation are justified to confirm the acceptable safety and efficacy of this strategy. Four such randomised controlled trials (collectively planned to include around 9000 participants) are underway, either using single cutoff timepoints for early versus late DOAC-administration initiation, or selecting DOAC-administration timing according to the severity and imaging features of the ischaemic stroke. The results of these trials should help to establish the optimal timing to initiate DOAC administration after recent ischaemic stroke and whether the timing should differ according to stroke severity. Results of these trials are expected from 2021.
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- 2019
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22. Noninvasive perfusion imaging of human brain tumors with EPISTAR
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Gaa, J., Warach, S., Wen, P., Thangaraj, V., Wielopolski, P., and Edelman, R. R.
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- 1996
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23. Clinical applications and techniques of echo-planar imaging
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Schmitt, Franz, Warach, S., Wielopolski, P., and Edelman, R. R.
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- 1994
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24. Magnetic Resonance Imaging Criteria for Thrombolysis in Acute Cerebral Infarct
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Hjort, N, Butcher, K, Davis, S M., Kidwell, C S., Koroshetz, W J., Röther, J, Schellinger, P D., Warach, S, and Østergaard, L
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- 2005
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25. Stroke aetiological classification reliability and effect on trial sample size: systematic review, meta-analysis and statistical modelling
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Abdul-Rahim, AH, Dickie, DA, Selvarajah, JR, Lees, KR, Quinn, TJ, Alexandrov, A, Bath, PM, Berge, E, Bluhmki, E, Bornstein, N, Chen, C, Claesson, L, Davis, SM, Donnan, G, Diener, HC, Fisher, M, Ginsberg, M, Gregson, B, Grotta, J, Hacke, W, Hennerici, MG, Hommel, M, Kaste, M, Lyden, P, Marler, J, Muir, K, Venketasubramanian, N, Sacco, R, Shuaib, A, Teal, P, Wahlgren, NG, Warach, S, Weimar, C, Abdul-Rahim, AH, Dickie, DA, Selvarajah, JR, Lees, KR, Quinn, TJ, Alexandrov, A, Bath, PM, Berge, E, Bluhmki, E, Bornstein, N, Chen, C, Claesson, L, Davis, SM, Donnan, G, Diener, HC, Fisher, M, Ginsberg, M, Gregson, B, Grotta, J, Hacke, W, Hennerici, MG, Hommel, M, Kaste, M, Lyden, P, Marler, J, Muir, K, Venketasubramanian, N, Sacco, R, Shuaib, A, Teal, P, Wahlgren, NG, Warach, S, and Weimar, C
- Abstract
BACKGROUND: Inter-observer variability in stroke aetiological classification may have an effect on trial power and estimation of treatment effect. We modelled the effect of misclassification on required sample size in a hypothetical cardioembolic (CE) stroke trial. METHODS: We performed a systematic review to quantify the reliability (inter-observer variability) of various stroke aetiological classification systems. We then modelled the effect of this misclassification in a hypothetical trial of anticoagulant in CE stroke contaminated by patients with non-cardioembolic (non-CE) stroke aetiology. Rates of misclassification were based on the summary reliability estimates from our systematic review. We randomly sampled data from previous acute trials in CE and non-CE participants, using the Virtual International Stroke Trials Archive. We used bootstrapping to model the effect of varying misclassification rates on sample size required to detect a between-group treatment effect across 5000 permutations. We described outcomes in terms of survival and stroke recurrence censored at 90 days. RESULTS: From 4655 titles, we found 14 articles describing three stroke classification systems. The inter-observer reliability of the classification systems varied from 'fair' to 'very good' and suggested misclassification rates of 5% and 20% for our modelling. The hypothetical trial, with 80% power and alpha 0.05, was able to show a difference in survival between anticoagulant and antiplatelet in CE with a sample size of 198 in both trial arms. Contamination of both arms with 5% misclassified participants inflated the required sample size to 237 and with 20% misclassification inflated the required sample size to 352, for equivalent trial power. For an outcome of stroke recurrence using the same data, base-case estimated sample size for 80% power and alpha 0.05 was n = 502 in each arm, increasing to 605 at 5% contamination and 973 at 20% contamination. CONCLUSIONS: Stroke aetiological cl
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- 2019
26. New Magnetic Resonance Imaging Techniques for Stroke Diagnosis and Treatment
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Fisher, M., primary and Warach, S., additional
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- 1997
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27. Comparison of Retrospective and Prospective Measurements of the National Institutes of Health Stroke Scale
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Baird, A. E., Dashe, J., Connor, A., Burzynski, C., Schlaug, G., and Warach, S.
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- 2000
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28. Using Pathophysiology in Acute Stroke Trials
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Baird, A.E. and Warach, S.
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- 1999
29. Do early CT signs reflect only pre-infarction? a comparative CT-DWI study: 5 Neuroimaging
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Jaillard Serradj, A., Hommel, M., Baird, A. E., Straroselkaya, I., Schaves, C., Edelman, R. R., Caplan, L., and Warach, S.
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- 1999
30. Advances of MRI in stroke
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Warach, S., primary
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- 2019
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31. Small vessel disease and clinical outcomes after IV rt-PA treatment
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Arba, F., Inzitari, D., Ali, M., Warach, S. J., Luby, M., Lees, K. R., Albers, Gregory W., Davis, Stephen M., Donnan, Geoffrey A., Fisher, Marc, Furlan, Anthony J., Grotta, James C., Hacke, Werner, Kang, Dong Wha, Kidwell, Chelsea, Koroshetz, Walter J., Lev, Michael H., Liebeskind, David S., Gregory Sorensen, A., Thijs, Vincent N., Thomalla, Götz, Wardlaw, Joanna M., and Wintermark, Max
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Male ,medicine.medical_specialty ,Pathology ,small vessel disease ,medicine.medical_treatment ,Clinical Neurology ,030204 cardiovascular system & hematology ,Logistic regression ,Ordinal regression ,magnetic resonance ,03 medical and health sciences ,0302 clinical medicine ,Modified Rankin Scale ,Internal medicine ,medicine ,Dementia ,Humans ,intravenous thrombolysis ,Stroke ,Aged ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Confounding ,Magnetic resonance imaging ,General Medicine ,Thrombolysis ,white matter changes ,Middle Aged ,medicine.disease ,stroke ,Magnetic Resonance Imaging ,clinical outcomes ,Neurology ,Cerebral Small Vessel Diseases ,Tissue Plasminogen Activator ,Cardiology ,Female ,Neurology (clinical) ,business ,030217 neurology & neurosurgery - Abstract
Introduction:\ud \ud Cerebral small vessel disease (SVD) contributes to dementia and disability in the elderly, and may negatively affect stroke outcomes. We aimed to evaluate to what extent single features and global burden of SVD detected with magnetic resonance (MR) are associated with worse outcomes in patients with ischaemic stroke treated with intravenous thrombolysis.\ud Methods:\ud \ud We accessed anonymized data and MR images from the Stroke Imaging Repository (STIR) and the Virtual International Stroke Trials Archive (VISTA) Imaging. We described SVD features using validated scales and quantified the global burden of SVD with a combined score. Our mainoutcome was the modified Rankin Scale (mRS) at 90 days after stroke. We used logistic regression and ordinal regression models (adjusted for age, sex, stroke severity, onset to treatment time) to examine the associations between each SVD feature, SVD global burden and clinical outcomes.\ud Results:\ud \ud A total of 259 patients had MR scans available at baseline (mean age±SD=68.7±15.5 years; 131 [49%] males). After adjustment for confounders, severe white matter changes were associated with disability (OR=5.14; 95%CI=2.30-11.48), functional dependency (OR=4.38; 95%CI=2.10-9.13) and worse outcomes in ordinal analysis (OR=2.71; 95%CI=1.25-5.85). SVD score was associated with disability (OR=1.66; 95%CI=1.03-2.66) and functional dependency (OR=1.47; 95%CI=1.00-2.45). Lacunes, enlarged perivascular spaces and brain atrophy showed no association with clinical outcomes.\ud Conclusion:\ud \ud Our results suggest that SVD negatively affects stroke outcomes after intravenous thrombolysis. Although white matter changes seem to be the major driver in relation to worse outcomes, global estimation of SVD is feasible and may provide helpful information.
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- 2017
32. Interdependence of Stroke Outcome Scales: Reliable Estimates from the Virtual International Stroke Trials Archive (VISTA)
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Goldie, F. C., Fulton, R. L., Frank, Benedikt, Lees, K. R., Alexandrov, A., Bath, P. W., Bluhmki, E., Claesson, L., Curram, J., Davis, S. M., Donnan, G., Diener, Hans Christoph, Fisher, M., Gregson, B., Grotta, J., Hacke, W., Hennerici, M. G., Hommel, M., Kaste, M., Lyden, P., Marler, J., Muir, K., Sacco, R., Shuaib, A., Teal, P., Wahlgren, N. G., Warach, S., and Weimar, Christian
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medicine.medical_specialty ,Archives ,business.industry ,medicine.medical_treatment ,Treatment outcome ,Medizin ,Outcome assessment ,medicine.disease ,Outcome (game theory) ,Clinical neurology ,Stroke ,Clinical trial ,User-Computer Interface ,Treatment Outcome ,Neurology ,Outcome Assessment, Health Care ,Stroke outcome ,Physical therapy ,Humans ,Medicine ,cardiovascular diseases ,business ,Stroke recovery - Abstract
Background and Purpose Clinical deficits from stroke are diverse, prompting measurement in trials by a range of outcome scales. Statistical and clinical advantage can be gained by combining scales into a global outcome provided combinations are chosen with limited correlations. We aimed to clarify the interdependence of outcome scales by systematic review of published data and by novel analysis of data from completed acute trials. Summary of Review We systematically searched ScienceDirect and PubMed to summarize published data on correlations between stroke outcome scales. We generated new data on correlations among salient scales at 90 days poststroke in patients from the Virtual International Stroke Trials Archive (VISTA). We calculated Pearson and Spearman-Rank correlation coefficients for continuous and ordinal measures, respectively. We also assessed partial correlations, adjusted for baseline National Institute of Health Stroke Scale (NIHSS), and age. Published estimates of interdependence were limited to small single-trial cohorts and gave divergent results. From the more extensive VISTA dataset, we found that the modified Rankin Scale at 90 days poststroke explained 80.8% of the National Institute of Health Stroke Scale at 90 days poststroke and 86·5% of the European Stroke Scale. National Institute of Health Stroke Scale explained 75.9% of the Barthel Index and 81·2% of the Scandinavian Stroke Scale. After adjustment, modified Rankin Scale explained 56.6% of National Institute of Health Stroke Scale, 75.2% of Barthel Index. National Institute of Health Stroke Scale explained 60.2% of Barthel Index. Conclusion Correlations and partial correlations among stroke outcome scales in trial datasets are higher than previously reported. The new estimates are more reliable for trial planning due to the sample size and diversity.
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- 2013
33. Selection for Delayed Intravenous Alteplase Treatment Based on a Prognostic Score
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Fulton, R. L., Lees, K. R., Bluhmki, E., Biegert, G., Albers, G. W., Davis, S. M., Donnan, G. A., Grotta, J. C., Hacke, W., Kaste, M., Von Kummer, R., Shuaib, A., Toni, Danilo, Alexandrov, A., Bath, P. W., Claesson, L., Curram, J., Diener, H. C., Fisher, M., Gregson, B., Hennerici, M. G., Hommel, M., Lyden, P., Marler, J., Muir, K., Sacco, R., Teal, P., Wahlgren, N. G., Warach, S., Weimar, C., Collaboration, Vista, Ecass Atlantis Ninds, and Epithet, Investigators
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medicine.medical_specialty ,medicine.medical_treatment ,Population ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,Fibrinolytic Agents ,Randomized controlled trial ,law ,Internal medicine ,Odds Ratio ,Humans ,Medicine ,030212 general & internal medicine ,education ,Stroke ,Randomized Controlled Trials as Topic ,education.field_of_study ,business.industry ,Patient Selection ,Thrombolysis ,Odds ratio ,Prognosis ,medicine.disease ,Confidence interval ,3. Good health ,Clinical trial ,Treatment Outcome ,Neurology ,Tissue Plasminogen Activator ,Medical emergency ,business ,030217 neurology & neurosurgery ,Fibrinolytic agent - Abstract
Background and Purpose Approved use of intravenous alteplase for ischemic stroke offers net benefit. Pooled randomized controlled trial analysis suggests additional patients could benefit but others be harmed with treatment initiated beyond 4·5 h after stroke onset. We proposed prognostic scoring methods to identify a strategy for patient selection. Methods We selected 500 patients treated by intravenous alteplase and 500 controls from Virtual International Stroke Trials Archive, matching modified Rankin score outcomes to those from pooled randomized controlled trial 4·5–6 h data. We ranked patients by prognostic score. We chose limits to optimize our sample for a net treatment benefit significant at P = 0·01 by Cochran–Mantel–Haenszel test and by ordinal regression. For validation, we had these applied to the pooled randomized controlled trial data for 4·5–6 h, testing for net benefit by Cochran–Mantel–Haenszel test, ordinal regression, and also by dichotomized outcomes: modified Rankin score 0–1, mortality and parenchymal hemorrhage type 2 bleeds. All analyses were adjusted for age and National Institutes of Health Stroke Scale. Results In the training dataset, limits of 56–95 on a prognostic score retained 714 patients in whom there was net benefit significant at P = 0·01. When applied to the 1120 patients in the pooled randomized controlled trial 4·5–6 h dataset, score limits of 56–95 retained 711 patients and gave odds ratio for improved modified Rankin score distribution of 1·13, 95% confidence interval 0·87–1·47, Cochran–Mantel–Haenszel P = 0·89. More patients achieved modified Rankin score 0–1 (odds ratio 1·44, 1·02–2·05, P = 0·04) but mortality and parenchymal hemorrhage type 2 bleeds were increased: odds ratio 1·56, 1·01–2·40, P = 0·04; odds ratio 15·6, 3·7–65·8, P = 0·0002, respectively. Conclusion Selection of patients between 4·5 and 6 h based on simple clinical measures failed to deliver a population in whom the alteplase effect would be safe and effective.
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- 2013
34. Predicting disability after ischemic stroke based on comorbidity index and stroke severity-from the virtual international stroke trials archive-acute collaboration.
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Phan T.G., Ma H., Van Ly J., Srikanth V., Lees K.R., Alexandrov A., Bluhmki E., Bornstein N., Claesson L., Davis S.M., Donnan G., Diener H.C., Fisher M., Ginsberg M., Gregson B., Grotta J., Hacke W., Hennerici M.G., Hommel M., Kaste M., Lyden P., Marler J., Muir K., Venketasubramanian N., Sacco R., Shuaib A., Teal P., Wahlgren N.G., Warach S., Weimar C., Chen C., Bath P.M., Clissold B.B., Phan T.G., Ma H., Van Ly J., Srikanth V., Lees K.R., Alexandrov A., Bluhmki E., Bornstein N., Claesson L., Davis S.M., Donnan G., Diener H.C., Fisher M., Ginsberg M., Gregson B., Grotta J., Hacke W., Hennerici M.G., Hommel M., Kaste M., Lyden P., Marler J., Muir K., Venketasubramanian N., Sacco R., Shuaib A., Teal P., Wahlgren N.G., Warach S., Weimar C., Chen C., Bath P.M., and Clissold B.B.
- Abstract
Background and aim: The availability and access of hospital administrative data [coding for Charlson comorbidity index (CCI)] in large data form has resulted in a surge of interest in using this information to predict mortality from stroke. The aims of this study were to determine the minimum clinical data set to be included in models for predicting disability after ischemic stroke adjusting for CCI and clinical variables and to evaluate the impact of CCI on prediction of outcome. Method(s): We leverage anonymized clinical trial data in the Virtual International Stroke Trials Archive. This repository contains prospective data on stroke severity and outcome. The inclusion criteria were patients with available stroke severity score such as National Institutes of Health Stroke Scale (NIHSS), imaging data, and outcome disability score such as 90-day Rankin Scale. We calculate CCI based on comorbidity data in this data set. For logistic regression, we used these calibration statistics: Nagelkerke generalised R2 and Brier score; and for discrimination we used: area under the receiver operating characteristics curve (AUC) and integrated discrimination improvement (IDI). The IDI was used to evaluate improvement in disability prediction above baseline model containing age, sex, and CCI. Result(s): The clinical data among 5,206 patients (55% males) were as follows: mean age 69 +/- 13 years, CCI 4.2 +/- 0.8, and median NIHSS of 12 (IQR 8, 17) on admission and 9 (IQR 5, 15) at 24 h. In Model 2, adding admission NIHSS to the baseline model improved AUC from 0.67 (95% CI 0.65-0.68) to 0.79 (95% CI 0.78-0.81). In Model 3, adding 24-h NIHSS to the baseline model resulted in substantial improvement in AUC to 0.90 (95% CI 0.89-0.91) and increased IDI by 0.23 (95% CI 0.22-0.24). Adding the variable recombinant tissue plasminogen activator did not result in a further change in AUC or IDI to this regression model. In Model 3, the variable NIHSS at 24 h explains 87.3% of the variance of
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- 2017
35. Predicting disability after ischemic stroke based on comorbidity index and stroke severity-from the virtual international stroke trials archive-acute collaboration
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Phan, TG, Clissold, Ben, Ma, H, Van Ly, J, Srikanth, V, Lees, KR, Alexandrov, A, Bath, PM, Bluhmki, E, Bornstein, N, Chen, C, Claesson, L, Davis, SM, Donnan, G, Diener, HC, Fisher, M, Ginsberg, M, Gregson, B, Grotta, J, Hacke, W, Hennerici, MG, Hommel, M, Kaste, M, Lyden, P, Marler, J, Muir, K, Venketasubramanian, N, Sacco, R, Shuaib, A, Teal, P, Wahlgren, NG, Warach, S, Weimar, C, Phan, TG, Clissold, Ben, Ma, H, Van Ly, J, Srikanth, V, Lees, KR, Alexandrov, A, Bath, PM, Bluhmki, E, Bornstein, N, Chen, C, Claesson, L, Davis, SM, Donnan, G, Diener, HC, Fisher, M, Ginsberg, M, Gregson, B, Grotta, J, Hacke, W, Hennerici, MG, Hommel, M, Kaste, M, Lyden, P, Marler, J, Muir, K, Venketasubramanian, N, Sacco, R, Shuaib, A, Teal, P, Wahlgren, NG, Warach, S, and Weimar, C
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- 2017
36. Statins and risk of poststroke hemorrhagic complications
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Scheitz, Jan F, MacIsaac, Rachael L, Bluhmki, E., Gregson, B., Donnan, G., Diener, H. C., Grotta, J., Marler, J., Teal, P., Hennerici, M. G., Wahlgren, N. G., Lyden, P., Abdul-Rahim, Azmil H, Bath, P. W., Sacco, R., Davis, S. M., Hacke, W., Warach, S., Fisher, M., Hommel, M., Kaste, M., Muir, K., Shuaib, A., Siegerink, Bob, Weimar, C., Alexandrov, A., Bornstein, N., Ginsberg, M., Bath, Philip M, Endres, Matthias, Lees, Kennedy R, Nolte, Christian H, VISTA collaboration, and Lees, K. R.
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Male ,Databases, Factual ,medicine.medical_treatment ,Medizin ,030204 cardiovascular system & hematology ,Severity of Illness Index ,0302 clinical medicine ,Odds Ratio ,complications [Stroke] ,mortality [Stroke] ,Stroke ,Hazard ratio ,adverse effects [Hydroxymethylglutaryl-CoA Reductase Inhibitors] ,Thrombolysis ,etiology [Cerebral Hemorrhage] ,drug therapy [Stroke] ,Treatment Outcome ,Psychotherapy, Group ,Female ,mortality [Cerebral Hemorrhage] ,Risk ,medicine.medical_specialty ,Statin ,medicine.drug_class ,Article ,03 medical and health sciences ,Internal medicine ,therapeutic use [Hydroxymethylglutaryl-CoA Reductase Inhibitors] ,Severity of illness ,medicine ,Humans ,cardiovascular diseases ,ddc:610 ,Aged ,Proportional Hazards Models ,Retrospective Studies ,Cerebral Hemorrhage ,Intracerebral hemorrhage ,business.industry ,Odds ratio ,medicine.disease ,Surgery ,Propensity score matching ,Neurology (clinical) ,Hydroxymethylglutaryl-CoA Reductase Inhibitors ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
Objective: To assess whether statin treatment before or after acute ischemic stroke (AIS) affects the risk of acute intracerebral hemorrhage (ICH), postacute ICH, and mortality within 90 days. Methods: Data were sought from the Virtual International Stroke Trials Archive, an international repository of clinical trials data. Using propensity score matching, we retrospectively compared patients with prior statin treatment and newly initiated statin within 3 days after AIS to patients without statin exposure. Outcomes of interest were acute symptomatic ICH (sICH), any acute ICH, postacute ICH, and mortality during follow-up of 3 months. Results: A total of 8,535 patients (mean age 70 years, 54% male, median baseline NIH Stroke Scale score 13) were analyzed. After propensity score matching, prior statin use was not strongly associated with sICH (adjusted odds ratio [OR] 1.33, 95% confidence interval [CI] 0.83–2.14) or any ICH (adjusted OR 1.35, 95% CI 0.92–1.98). There was no evidence of an interaction between prior statin use and thrombolysis. New initiation of statins was not associated with postacute ICH (adjusted hazard ratio [HR] 1.60, 95% CI 0.70–3.65). There was a signal towards lower 90-day mortality in patients with prior statin use (adjusted HR 0.84, 95% CI 0.70–1.00) and especially early initiation of statins (adjusted HR 0.67, 95% CI 0.46–0.97). Conclusions: Statin use prior to AIS was not associated with early hemorrhagic complications, irrespective of treatment with thrombolysis. New initiation of statin treatment early after AIS did not affect risk of postacute ICH, but might be associated with reduced mortality.
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- 2016
37. Stroke Severity and Comorbidity Index for Prediction of Mortality after Ischemic Stroke from the Virtual International Stroke Trials Archive-Acute Collaboration
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Phan, Thanh G, Clissold, Benjamin, Ly, John, Ma, Henry, Moran, Chris, Srikanth, Velandai, Lees, K R, Alexandrov, A, Bath, P M, Bluhmki, E, Bornstein, N, Claesson, L, Davis, S M, Donnan, G, Diener, Hans Christoph, Fisher, M, Ginsberg, M, Gregson, B, Grotta, J, Hacke, W, Hennerici, M G, Hommel, M, Kaste, M, Lyden, P, Marler, J, Muir, K, Sacco, R, Shuaib, A, Teal, P, Wahlgren, N G, Warach, S, Weimar, Christian, Neurologian yksikkö, and Clinicum
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medicine.medical_specialty ,Databases, Factual ,medicine.medical_treatment ,Medizin ,Severity of Illness Index ,3124 Neurology and psychiatry ,Brain Ischemia ,03 medical and health sciences ,User-Computer Interface ,0302 clinical medicine ,Interquartile range ,Predictive Value of Tests ,Risk Factors ,Severity of illness ,Medicine ,Humans ,030212 general & internal medicine ,cardiovascular diseases ,Cooperative Behavior ,Stroke ,Aged ,Aged, 80 and over ,RISK ,Ischemic stroke ,RECLASSIFICATION ,business.industry ,Rehabilitation ,Regression analysis ,Thrombolysis ,Middle Aged ,Models, Theoretical ,medicine.disease ,mortality ,Confidence interval ,3. Good health ,TISSUE ,Predictive value of tests ,Emergency medicine ,Physical therapy ,Surgery ,Neurology (clinical) ,prognosis ,Cardiology and Cardiovascular Medicine ,business ,Charlson Comorbidity Index ,030217 neurology & neurosurgery - Abstract
M. Kaste on työryhmän VISTA-Acute Collaboration jäsen. Background: There is increasing interest in the use of administrative data (incorporating comorbidity index) and stroke severity score to predict ischemic stroke mortality. The aim of this study was to determine the optimal timing for the collection of stroke severity data and the minimum clinical dataset to be included in models of stroke mortality. To address these issues, we chose the Virtual International Stroke Trials Archive (VISTA), which contains National Institutes of Health Stroke Scale (NIHSS) on admission and at 24 hours, as well as outcome at 90 days. Methods: VISTA was searched for patients who had baseline and 24-hour NIHSS. Improvement in regression models was performed by the net reclassification improvement (NRI) method. Results: The clinical data among 5206 patients were mean age, 69 +/- 13; comorbidity index, 3.3 +/- .9; median NIHSS at baseline, 12 (interquartile range [IQR] 8-17); NIHSS at 24 hours, 9 (IQR 8-15); and death at 90 days in 15%. The baseline model consists of age, gender, and comorbidity index. Adding the baseline NIHSS to model 1 improved the NRI by 0.671 (95% confidence interval [CI] 0.595-0.747) [or 67.1% correct reclassification between model 1 and model 2]. Adding the 24 hour NIHSS term to model 1 (model 3) improved the NRI by 0.929 (95% CI 0.857-1.000) for model 3 versus model 1. Adding the variable thrombolysis to model 3 (model 4) improve NRI by 0.1 (95% CI 0.023-0.178) [model 4 versus model 3]. Conclusion: The optimal model for the prediction of mortality was achieved by adding the 24-hour NIHSS and thrombolysis to the baseline model.
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- 2016
38. Impact of heart rate on admission on mortality and morbidity in acute ischaemic stroke patients - results from VISTA
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Nolte, C H, Erdur, H, Grittner, U, Schneider, A, Piper, S K, Scheitz, J F, Wellwood, I, Bath, P M W, Diener, Hans Christoph, Lees, K R, Endres, M, Alexandrov, A, Bluhmki, E, Bornstein, N, Chen, C, Claesson, L, Davis, S M, Donnan, G, Fisher, M, Ginsberg, M, Gregson, B, Grotta, J, Hacke, W, Hennerici, M G, Hommel, M, Kaste, M, Lyden, P, Marler, J, Muir, K, Sacco, R, Shuaib, A, Teal, P, Venketasubramanian, N, Wahlgren, N G, Warach, S, and Weimar, Christian
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Male ,medicine.medical_specialty ,Heart disease ,acute stroke ,recurrent stroke ,Medizin ,heart failure ,030204 cardiovascular system & hematology ,Brain Ischemia ,Coronary artery disease ,03 medical and health sciences ,0302 clinical medicine ,Patient Admission ,Modified Rankin Scale ,Heart Rate ,Internal medicine ,Atrial Fibrillation ,medicine ,Humans ,cardiovascular diseases ,Myocardial infarction ,Stroke ,Aged ,Aged, 80 and over ,business.industry ,Hazard ratio ,Atrial fibrillation ,Middle Aged ,medicine.disease ,mortality ,Neurology ,Heart failure ,Cardiology ,Female ,Neurology (clinical) ,business ,030217 neurology & neurosurgery - Abstract
BACKGROUND AND PURPOSE: Elevated heart rate (HR) is associated with worse outcomes in patients with cardiovascular disease. Its predictive value in acute stroke patients is less well established. We investigated the effects of HR on admission in acute ischaemic stroke patients. METHODS: Using the Virtual International Stroke Trials Archive (VISTA) database, the association between HR in acute stroke patients without atrial fibrillation and the pre-defined composite end-point of (recurrent) ischaemic stroke, transient ischaemic attack (TIA), myocardial infarction (MI) and vascular death within 90 days was analysed. Pre-defined secondary outcomes were the composite end-point components and any death, decompensated heart failure and degree of functional dependence according to the modified Rankin Scale after 90 days. HR was analysed as a categorical variable (quartiles). RESULTS: In all, 5606 patients were available for analysis (mean National Institutes of Health Stroke Scale 13; mean age 67 years; mean HR 77 bpm; 44% female) amongst whom the composite end-point occurred in 620 patients (11.1%). Higher HR was not associated with the composite end-point. The frequencies of secondary outcomes were 3.2% recurrent stroke (n = 179), 0.6% TIA (n = 35), 1.8% MI (n = 100), 6.8% vascular death (n = 384), 15.0% any death (n = 841) and 2.2% decompensated heart failure (n = 124). Patients in the highest quartile (HR> 86 bpm) were at increased risk for any death [adjusted hazard ratio (95% confidence interval) 1.40 (1.11-1.75)], decompensated heart failure [adjusted hazard ratio 2.20 (1.11-4.37)] and worse modified Rankin Scale [adjusted odds ratio 1.29 (1.14-1.52)]. CONCLUSIONS: In acute stroke patients, higher HR (>86 bpm) is linked to mortality, heart failure and higher degree of dependence after 90 days but not to recurrent stroke, TIA or MI.
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- 2016
39. Development, Expansion, and Use of a Stroke Clinical Trials Resource for Novel Exploratory Analyses
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Ali, Myzoon, Bath, Philip, Brady, Marian, Davis, Stephen, Diener, Hans Christoph, Donnan, Geoffrey, Fisher, Marc, Hacke, Werner, Hanley, Daniel F., Luby, Marie, Tsivgoulis, G., Wahlgren, Nils, Steven Warach, Steven, Lees, Kennedy R., Lees, K. R., Alexandrov, A., Bath, P. W., Bluhmki, E., Claesson, L., Davis, S. M., Gregson, B., Grotta, J., Hennerici, M. G., Hommel, M., Kaste, M., Lyden, P., Marler, J., Muir, K., Sacco, R., Shuaib, A., Teal, P., Wahlgren, N. G., Warach, S., Weimar, Christian, Ashburn, A., Barer, D., Bowen, A., Brodie, E., Corr, S., Drummond, A., Edmans, J., English, C., Gladman, J., Kalra, L., Langhorne, P., Lincoln, N., Logan, P., Mead, G., Patchick, E., Pollock, A., Pomeroy, V., Rodgers, H., Sackley, C., Shaw, L., Sunnerhagen, K. S., Tyson, S., Vliet, P. van, Whiteley, M., Albers, G., Furlan, T., Kidwell, C., Koroshetz, W., Lev, M., Sorensen, G., Wardlaw, J., Wintermark, M., Hanley, D. F., Steiner, T., Mayer, S., Molina, C., and Numminen, H.
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Diagnostic Imaging ,medicine.medical_specialty ,Databases, Factual ,education ,Medizin ,MEDLINE ,Physical medicine and rehabilitation ,Resource (project management) ,medicine ,Humans ,Registries ,cardiovascular diseases ,Clinical care ,Stroke ,health care economics and organizations ,Cerebral Hemorrhage ,Clinical Trials as Topic ,Data collection ,business.industry ,Communication ,Data Collection ,Stroke Rehabilitation ,medicine.disease ,Test (assessment) ,Clinical trial ,Treatment Outcome ,Neurology ,Physical therapy ,Registry data ,business - Abstract
Introduction Analysis of reliable registry data can direct future research to influence clinical care. Data from the Virtual International Stroke Trials Archive have been used to test hypotheses and inform trial design. We sought to expand Virtual International Stroke Trials Archive into a broader stroke resource with new opportunities for research and international collaboration. Methods Using procedures initially developed for an acute stroke trial archive, we invited trialists to lodge data on rehabilitation, secondary prevention, intracerebral haemorrhage, imaging, and observational stroke studies. Results We have extended Virtual International Stroke Trials Archive into six subsections: Virtual International Stroke Trials Archive-Acute ( n = 28 190 patients’ data), Virtual International Stroke Trials Archive-Rehab ( n = 10 194), Virtual International Stroke Trials Archive-intracerebral haemorrhage ( n = 1829), Virtual International Stroke Trials Archive-Prevention, Virtual International Stroke Trials Archive-Imaging ( n = 1300), and Virtual International Stroke Trials Archive-Plus ( n = 6573). Enrollment continues, with commitments for the contribution of six further trials to Virtual International Stroke Trials Archive-Prevention, 13 trials to Virtual International Stroke Trials Archive-Rehab, and one registry to Virtual International Stroke Trials Archive-Plus. Data on age, type of stroke, medical history, outcomes by modified Rankin scale and Barthel Index (BI), mortality, and adverse events are available for analyses. The Virtual International Stroke Trials Archive network encourages the development of young investigators and provides opportunities for international peer review and collaboration. Conclusions Application of the original Virtual International Stroke Trials Archive concepts beyond acute stroke trials can extend the value of clinical research at low cost, without threatening commercial or intellectual property interests. This delivers valuable research output to inform the efficiency of future stroke research. We invite stroke researchers to participate actively in Virtual International Stroke Trials Archive and encourage the extension of Virtual International Stroke Trials Archive principles to other disease areas.
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- 2012
40. Initial blood pressure and adverse cardiac events following acute ischaemic stroke: An individual patient data pooled analysis from the VISTA database
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Ishiguchi, Hironori, Huang, Bi, El-Bouri, Wahbi K., Dawson, Jesse, Lip, Gregory Y. H., Abdul-Rahim, Azmil H., Lees (Chair), K.R., Alexandrov, A., Bath, P.M., Bluhmki, E., Bornstein, N., Chen, C., Claesson, L., Curram, J., Davis, S.M., Diener, H-C., Donnan, G., Fisher, M., Ginsberg, M., Gregson, B., Grotta, J., Hacke, W., Hennerici, M.G., Hommel, M., Kaste, M., Lyden, P., Marler, J., Muir, K., Roffe, C., Sacco, R., Shuaib, A ., Teal, P., Venketasubramanian, N., Wahlgren, N.G., and Warach, S.
- Abstract
Background: Adverse cardiac events following ischaemic stroke (stroke-heart syndrome, SHS) pose a clinical challenge. We investigated the association between initial blood pressure at stroke presentation and the risk of SHS.Methods: We utilised data from the Virtual International Stroke Trials Archive (VISTA). We defined SHS as the incidence of cardiac complications within 30 days post-ischaemic stroke. These presentations included acute coronary syndrome encompassing myocardial injury, heart failure/left ventricular dysfunction, atrial fibrillation/flutter, other arrhythmia/electrocardiogram abnormalities, and cardiorespiratory arrest. Using Cox proportional hazards models, we assessed the risk trajectories for developing SHS and its presentations associated with initial blood pressure. We also explored the risk trajectories for 90-day mortality related to initial blood pressure.Results: From 16,095 patients with acute ischaemic stroke, 14,965 (mean age 69 ± 12 years; 55% male) were analysed. Of these, 1774 (11.8%) developed SHS. The risk of SHS and initial blood pressure showed a U-shaped relationship. The lowest blood pressures (⩽130 mmHg systolic and ⩽55 mmHg diastolic) were associated with the highest risks (adjusted hazard ratio [95%confidence interval]: 1.40 [1.21–1.63]; p< 0.001, 1.71 [1.39–2.10]; p< 0.001, respectively, compared to referential blood pressure range). Cardiorespiratory arrest posed the greatest risk at higher blood pressure levels (2.34 [1.16–4.73]; p= 0.017 for systolic blood pressure >190 mmHg), whereas other presentations exhibited the highest risk at lower pressures. The 90-day mortality risk also followed a U-shaped distribution, with greater risks observed at high blood pressure thresholds.Conclusions: There is a U-shaped relationship between initial blood pressure at ischaemic stroke presentation and the risk of subsequent SHS.
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- 2024
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41. Stroke-heart syndrome and early mortality in patients with acute ischaemic stroke using hierarchical cluster analysis: An individual patient data pooled analysis from the VISTA database
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Ishiguchi, Hironori, Huang, Bi, El-Bouri, Wahbi K., Lip, Gregory Y. H., Abdul-Rahim, Azmil H., Lees (Chair), K.R., Alexandrov, A., Bath, P.M., Bluhmki, E., Bornstein, N., Chen, C., Claesson, L., Curram, J., Davis, S.M., Diener, H-C., Donnan, G., Fisher, M., Ginsberg, M., Gregson, B., Grotta, J., Hacke, W., Hennerici, M.G., Hommel, M., Kaste, M., Lyden, P., Marler, J., Muir, K., Roffe, C., Sacco, R., Shuaib, A ., Teal, P., Venketasubramanian, N., Wahlgren, N.G., and Warach, S.
- Abstract
Background: The patient clinical phenotypes at particularly high risk for early cardiac complications after a recent acute ischaemic stroke (AIS), that is, stroke-heart syndrome (SHS), remain poorly defined. We utilised hierarchical cluster analysis to identify specific phenotypic profiles associated with this risk.Methods: We gathered data on patients with AIS from the Virtual International Stroke Trials Archive, a global repository of clinical trial data. We examined cardiac complications within 30 days post-stroke, including acute coronary syndrome, heart failure, arrhythmias and cardiorespiratory arrest. We employed hierarchical cluster analysis to define distinct phenotypic risk profiles. The incidence/risk of SHS and 90-day mortality were compared across these profiles.Results: We included 12,482 patients (mean age 69 ± 12 years; 55% male), yielding five phenotypes: Profile 1 (‘elderly and AF’), Profile 2 (‘young and smoker’), Profile 3 (‘young’), Profile 4 (‘cardiac comorbidities’) and Profile 5 (‘hypertension with atherosclerotic comorbidities’). Profiles 4 and 1 exhibited the highest risk for SHS (adjusted HR (95% CI): 2.01 (1.70–2.38) and 1.26 (1.05–1.51), respectively, compared to Profile 3), while Profiles 5 and 2 showed moderate risk and Profile 3 had the lowest risk. Although Profiles 1 and 4 were at the highest risk for most SHS presentations, Profile 5 had the highest risk for cardiorespiratory arrest (adjusted HR (95% CI): 2.99 (1.22–7.34)). The 90-day mortality risk was stratified by phenotype, with the highest risk observed in Profiles 5, and 4.Conclusions: Hierarchical cluster analysis effectively identified phenotypes with the highest risk of SHS and early mortality in patients with AIS.
- Published
- 2024
- Full Text
- View/download PDF
42. Recommendations for Standards Regarding Preclinical Neuroprotective and Restorative Drug Development
- Author
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Feinklestein, SP, Fisher, M, Furland, AJ, Goldstein, LB, Gorelick, PB, Kaste, M, Lees, KR, Traystman, RJ, Albers, GW, Anwer, UE, Ashwood, T, Barone, FC, Basta, SL, Bogousslavsky, J, Buchan, AM, Cady, WJ, Chan, PH, Clemens, JA, Cox, BF, Craddock, RE, Cramer, SC, del Zoppo, GJ, Dielrich, WD, Elliott, P, Faden, AI, Feuerstein, GZ, Ginsberg, MD, Gold, M, Greene, WL, Hall, ED, Hsu, CY, Hunter, AJ, Lai, M, Lesko, LM, Levy, DE, Li, FH, Locke, KW, Lodge, D, Lowe, D, Marcoux, FW, McCulloch, J, McDermott, J, Meibach, R, Messersmith, EK, Moseley, M, Moskowitz, MA, Mueller, AL, Munro, F, Nudo, RJ, Oeda, J, Ohlstein, EH, Parsons, A, Patmore, L, Poole, RM, Pschorn, U, Pulsinelli, WA, Sacco, RL, Saeki, S, Salazar-Grueso, E, Sandage, BW, Schallert, T, Schielke, GP, Sharkey, J, Sotak, CH, Steiger, B, Storall, S, Takahashi, Y, Tumas, D, Van Bruggen, N, Versavel, M, Vornov, J, Walker, MD, Wallin, B, Wang, J, Warach, S, Wells, DS, Witcher, JA, and Round, STAI
- Subjects
Primates ,medicine.medical_specialty ,Remission, Spontaneous ,Drug Evaluation, Preclinical ,Alternative medicine ,Psychological intervention ,Guidelines as Topic ,Neuroprotection ,Neuroprotective drug ,Sex Factors ,Neuroprotective Drugs ,Outcome Assessment, Health Care ,Animals ,Medicine ,Intensive care medicine ,Acute ischemic stroke ,Advanced and Specialized Nursing ,business.industry ,Enzymes ,Rats ,Stroke ,Clinical trial ,Disease Models, Animal ,Drug Combinations ,Neuroprotective Agents ,Drug development ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,business - Abstract
Abstract —The plethora of failed clinical trials with neuroprotective drugs for acute ischemic stroke have raised justifiable concerns about how best to proceed for the future development of such interventions. Preclinical testing of neuroprotective drugs is an important aspect of assessing their therapeutic potential, but guidelines concerning how to perform preclinical development of purported neuroprotective drugs for acute ischemic stroke are lacking. This conference of academicians and industry representatives was convened to suggest such guidelines for the preclinical evaluation of neuroprotective drugs and to recommend to potential clinical investigators the data they should review to reassure themselves that a particular neuroprotective drug has a reasonable chance to succeed in an appropriately designed clinical trial. Without rigorous, robust, and detailed preclinical evaluation, it is unlikely that novel neuroprotective drugs will prove to be effective when tested in large, time-consuming, and expensive clinical trials. Additionally, similar recommendations are provided for drugs with the potential to enhance recovery after acute ischemic stroke, a burgeoning new field with great potential but little currently available data. The suggestions contained in this document are meant to serve as overall guidelines that must be adapted to the individual characteristics related to particular drugs and their preclinical and clinical development needs.
- Published
- 1999
43. Googling Stroke ASPECTS to determine disability: Exploratory analysis from vista-acute collaboration.
- Author
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Davis S.M., Chen J., Phan T.G., Lees K.R., Ali M., Alexandrov A., Bath P.M., Bluhmki E., Bornstein N., Claesson L., Beare R., Donnan G., Diener H.C., Fisher M., Ginsberg M., Gregson B., Grotta J., Hacke W., Hennerici M.G., Hommel M., Kaste M., Lyden P., Marler J., Muir K., Sacco R., Shuaib A., Teal P., Wahlgren N.G., Warach S., Weimar C., Davis S.M., Chen J., Phan T.G., Lees K.R., Ali M., Alexandrov A., Bath P.M., Bluhmki E., Bornstein N., Claesson L., Beare R., Donnan G., Diener H.C., Fisher M., Ginsberg M., Gregson B., Grotta J., Hacke W., Hennerici M.G., Hommel M., Kaste M., Lyden P., Marler J., Muir K., Sacco R., Shuaib A., Teal P., Wahlgren N.G., Warach S., and Weimar C.
- Abstract
The summed Alberta Stroke Program Early CT Score (ASPECTS) is useful for predicting stroke outcome. The anatomical information in the CT template is rarely used for this purpose because traditional regression methods are not adept at handling collinearity (relatedness) among brain regions. While penalized logistic regression (PLR) can handle collinearity, it does not provide an intuitive understanding of the interaction among network structures in a way that eigenvector method such as PageRank can (used in Google search engine). In this exploratory analysis we applied graph theoretical analysis to explore the relationship among ASPECTS regions with respect to disability outcome. The Virtual International Stroke Trials Archive (VISTA) was searched for patients who had infarct in at least one ASPECTS region (ASPECTS <=9, ASPECTS=10 were excluded), and disability (modified Rankin score/mRS). A directed graph was created from a cross correlation matrix (thresholded at false discovery rate of 0.01) of the ASPECTS regions and demographic variables and disability (mRS>2). We estimated the network-based importance of each ASPECTS region by comparing PageRank and node strength measures. These results were compared with those from PLR. There were 185 subjects, average age 67.5+/- 12.8 years (55% Males). Model 1: demographic variables having no direct connection with disability, the highest PageRank was M2 (0.225, bootstrap 95% CI 0.215-0.347). Model 2: demographic variables having direct connection with disability, the highest PageRank were M2 (0.205, bootstrap 95% CI 0.194-0.367) and M5 (0.125, bootstrap 95% CI 0.096-0.204). Both models illustrate the importance of M2 region to disability. The PageRank method reveals complex interaction among ASPECTS regions with respects to disability. This approach may help to understand the infarcted brain network involved in stroke disability.Copyright © 2015 Beare et al.
- Published
- 2015
44. Googling stroke ASPECTS to determine disability: Exploratory analysis from VISTA-acute collaboration.
- Author
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Wahlgren N.G., Lyden P., Marler J., Muir K., Sacco R., Shuaib A., Teal P., Warach S., Weimar C., Beare R., Chen J., Phan T.G., Lees K.R., Ali M., Alexandrov A., Bath P.M., Bluhmki E., Bornstein N., Claesson L., Davis S.M., Donnan G., Diener H.C., Fisher M., Ginsberg M., Gregson B., Grotta J., Hacke W., Hennerici M.G., Hommel M., Kaste M., Wahlgren N.G., Lyden P., Marler J., Muir K., Sacco R., Shuaib A., Teal P., Warach S., Weimar C., Beare R., Chen J., Phan T.G., Lees K.R., Ali M., Alexandrov A., Bath P.M., Bluhmki E., Bornstein N., Claesson L., Davis S.M., Donnan G., Diener H.C., Fisher M., Ginsberg M., Gregson B., Grotta J., Hacke W., Hennerici M.G., Hommel M., and Kaste M.
- Abstract
The summed Alberta Stroke Program Early CT Score (ASPECTS) is useful for predicting stroke outcome. The anatomical information in the CT template is rarely used for this purpose because traditional regression methods are not adept at handling collinearity (relatedness) among brain regions. While penalized logistic regression (PLR) can handle collinearity, it does not provide an intuitive understanding of the interaction among network structures in a way that eigenvector method such as PageRank can (used in Google search engine). In this exploratory analysis we applied graph theoretical analysis to explore the relationship among ASPECTS regions with respect to disability outcome. The Virtual International Stroke Trials Archive (VISTA) was searched for patients who had infarct in at least one ASPECTS region (ASPECTS 9, ASPECTS=10 were excluded), and disability (modified Rankin score/mRS). A directed graph was created from a cross correlation matrix (thresholded at false discovery rate of 0.01) of the ASPECTS regions and demographic variables and disability (mRS>2). We estimated the network-based importance of each ASPECTS region by comparing PageRank and node strength measures. These results were compared with those from PLR. There were 185 subjects, average age 67.5+/- 12.8 years (55% Males). Model 1: demographic variables having no direct connection with disability, the highest PageRank was M2 (0.225, bootstrap 95% CI 0.215-0.347). Model 2: demographic variables having direct connection with disability, the highest PageRank were M2 (0.205, bootstrap 95% CI 0.194-0.367) and M5 (0.125, bootstrap 95% CI 0.096-0.204). Both models illustrate the importance of M2 region to disability. The PageRank method reveals complex interaction among ASPECTS regions with respects to disability. This approach may help to understand the infarcted brain network involved in stroke disability.Copyright © 2015 Beare et al. This is an open access article distributed under the terms of the Cr
- Published
- 2015
45. Hyperintense vessel sign on fluid-attenuated inversion recovery MR imaging is reduced by gadolinium
- Author
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Dani, K.A., Latour, L.L., and Warach, S.
- Abstract
The HVS on FLAIR imaging is a useful marker of acute ischemic stroke. We investigated whether prior administration of gadolinium-based contrast hindered detection of this sign on images from subjects with acute nonlacunar ischemic stroke
- Published
- 2012
46. MRI as witness: ready for prime-time?
- Author
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Wu, O, Song, Ss, Ritter, C, Latour, Ll, Yoo, Aj, Lorenzano, S, Chaudhry, Za, Sorensen, Ag, Schwamm, Lh, Warach, S, and MR WITNESS Investigators
- Published
- 2011
47. Magnetic Resonance Imaging
- Author
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Robert R. Edelman and Warach S
- Subjects
Physics of magnetic resonance imaging ,Relaxometry ,medicine.diagnostic_test ,Interventional magnetic resonance imaging ,Magnetic resonance microscopy ,business.industry ,Magnetic resonance force microscopy ,Magnetic resonance spectroscopic imaging ,Magnetic resonance imaging ,General Medicine ,Nuclear magnetic resonance ,medicine ,Spin echo ,business - Published
- 1993
48. Whole-brain Arterial Spin Labeling Perfusion MR Imaging in Patients With Acute Stroke
- Author
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Bokkers, R.P., Warach, S., Osch, M.J. van, Duyn, J., and Latour, L.L.
- Published
- 2010
49. The Virtual International Stroke Trials Archive
- Author
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Ali, M., Bath, P.M.W., Curram, J., Davis, S.M., Diener, H.-C., Donnan, G.A., Fisher, M., Gregson, B.A., Grotta, J., Hacke, W., Hennerici, M.G., Hommel, M., Kaste, M., Marler, J.R., Sacco, R.L., Teal, P., Wahlgren, N.-G., Warach, S., Weir, C.J., and Lees, K.R.
- Published
- 2007
50. Dose escalation of desmoteplase for acute ischemic stroke (DEDAS): evidence of safety and efficacy 3 to 9 hours after stroke onset
- Author
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Al, R.Y., Albers, G.W., Eyding, D., Furlan, A.J., Hacke, W.l, Lees, K.R., Rowley, H.A., Sachara, C., Soehngen, M., and Warach, S.
- Abstract
Background and Purpose: Desmoteplase is a novel plasminogen activator with favorable features in vitro compared with available agents. This study evaluated safety and efficacy of intravenous (IV) desmoteplase in patients with perfusion/diffusion mismatch on MRI 3 to 9 hours after onset of acute ischemic stroke.\ud \ud Methods: DEDAS was a placebo-controlled, double-blind, randomized, dose-escalation study investigating doses of 90 μg/kg and 125 μg/kg desmoteplase. Eligibility criteria included baseline National Institute of Health Stroke Scale (NIHSS) scores of 4 to 20 and MRI evidence of perfusion/diffusion mismatch. The safety end point was the rate of symptomatic intracranial hemorrhage. Primary efficacy co-end points were MRI reperfusion 4 to 8 hours after treatment and good clinical outcome at 90 days. The primary analyses were intent-to-treat. Before unblinding, a target population, excluding patients violating specific MRI criteria, was defined.\ud \ud Results: Thirty-seven patients were randomized and received treatment (intent-to-treat; placebo: n=8; 90 μg/kg: n=14; 125 μg/kg: n=15). No symptomatic intracranial hemorrhage occurred. Reperfusion was achieved in 37.5% (95% CI [8.5; 75.5]) of placebo patients, 18.2% (2.3; 51.8) of patients treated with 90 μg/kg desmoteplase, and 53.3% (26.6; 78.7) of patients treated with 125 μg/kg desmoteplase. Good clinical outcome at 90 days occurred in 25.0% (3.2; 65.1) treated with placebo, 28.6% (8.4; 58.1) treated with 90 μg/kg desmoteplase and 60.0% (32.3; 83.7) treated with 125 μg/kg desmoteplase. In the target population (n=25), the difference compared with placebo increased and was statistically significant for good clinical outcome with 125 μg/kg desmoteplase (P=0.022).\ud \ud Conclusions: Treatment with IV desmoteplase 3 to 9 hours after ischemic stroke onset appears safe. At a dose of 125 μg/kg desmoteplase appeared to improve clinical outcome, especially in patients fulfilling all MRI criteria. The results of DEDAS generally support the results of its predecessor study, Desmoteplase in Acute Ischemic Stroke (DIAS).
- Published
- 2006
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