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Anadani M, Maier B, Escalard S, Labreuche J, de Havenon A, Sabben C, Lapergue B, Mistry EA, Gory B, Spiotta AM, Richard S, Sibon I, Desilles JP, Blanc R, Piotin M, Mazighi M. Safety and efficacy of intensive systolic blood pressure lowering after successful endovascular therapy: a post hoc analysis of the BP TARGET trial. J Neurointerv Surg 2023; 15:e142-e147. [PMID: 36220337 DOI: 10.1136/jnis-2022-019130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Accepted: 08/28/2022] [Indexed: 11/03/2022]
Abstract
BACKGROUND The Safety and Efficacy of Intensive Blood Pressure Lowering after Successful Endovascular Therapy in Acute Ischaemic Stroke (BP TARGET) trial demonstrated no benefit from intensive systolic blood pressure (SBP) treatment after successful reperfusion with endovascular therapy. However, it remains unknown if the response to blood pressure treatment is modified by other factors. OBJECTIVE To carry out a post hoc analysis of the BP TARGET trial data to determine if the response to blood pressure treatment is modified by factors such as age, history of hypertension, recanalization status, location of occlusion, diabetes, hyperglycemia, or pretreatment with intravenous thrombolysis. METHODS This is a post hoc analysis of the BP TARGET trial. Patients were divided into groups based on age, diabetes, blood glucose, site of occlusion, history of hypertension, and pretreatment with intravenous thrombolysis. The primary outcome was any intraparenchymal hemorrhage. RESULTS 318 patients were included. Diabetes modified the treatment effect on favorable functional outcome (Pheteogenity=0.041). There was a trend towards benefit from intensive SBP treatment in diabetic patients (OR=2.81; 95% CI 0.88 to 8.88; p=0.08) but not in non-diabetic patients (OR=0.75; 95% 0.45 to 126; p 0.28). Age, location of occlusion, admission SBP, pretreatment with intravenous thrombolysis, and history of hypertension did not modify the effect of intensive SBP treatment on any of the outcomes. CONCLUSION The effect of SBP lowering treatment was not modified by age, location of occlusion history of hypertension, intravenous thrombolysis, and admission SBP. Diabetes modified the effect of intensive SBP lowering treatment, and there was a trend towards benefit from intensive SBP treatment in diabetic patients. This finding is hypothesis generating and requires further validation.
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Affiliation(s)
- Mohammad Anadani
- Neurosurgery, Medical University of South Carolina, Charleston, SC, USA
| | - Benjamin Maier
- Department of Interventional Neuroradiology, Adolphe de Rothschild Ophthalmological Foundation, Paris, France
| | - Simon Escalard
- Departement of Interventional Neuroradiology, Fondation Rothschild Hospital, Paris, France
| | | | - Adam de Havenon
- Department of Neurology, Yale University, New Haven, Connecticut, USA
| | - Candice Sabben
- Department of Neurology, Fondation Rothschild Hospital, paris, France
| | | | - Eva A Mistry
- Department of Neurology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Benjamin Gory
- Department of Diagnostic and Interventional Neuroradiology, CHRU Nancy, Nancy, Lorraine, France
| | - Alejandro M Spiotta
- Department of Neurosurgery, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Sébastien Richard
- Neurology Stroke Unit, University Hospital Centre Nancy, Nancy, France
| | | | | | - Raphael Blanc
- Department of Interventional Neuroradiology, Fondation Rothschild, Paris, Île-de-France, France
| | - Michel Piotin
- Departement of Interventional Neuroradiology, Fondation Rothschild Hospital, Paris, France
| | - Mikaël Mazighi
- Departement of Interventional Neuroradiology, Fondation Rothschild Hospital, Paris, France
- Department of Neurology, GH Lariboisiere Fernand-Widal, Paris, France
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Anadani M, Maïer B, Escalard S, Labreuche J, de Havenon A, Sabben C, Lapergue B, Gory B, Richard S, Sibon I, Desilles JP, Blanc R, Piotin M, Mazighi M. Magnitude of Blood Pressure Change After Endovascular Therapy and Outcomes: Insight From the BP-TARGET Trial. Stroke 2022; 53:719-727. [PMID: 35109685 DOI: 10.1161/strokeaha.121.036701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE To assess the association between systolic blood pressure change (ΔSBP) at different time intervals after successful reperfusion with radiographic and clinical outcomes. METHODS This is a post hoc analysis of the BP-TARGET multicenter trial (Blood Pressure Target in Acute Stroke to Reduce Hemorrhage After Endovascular Therapy). ΔSBP was defined as end of procedure SBP minus mean SBP at different time intervals (15-60 minutes, 1-6 hours, and 6-24 hours postprocedure). The primary outcome was the poor functional outcome (90-day modified Rankin Scale score 3-6). RESULTS We included a total of 267 patients (130 in the intensive treatment group). Compared with patients with favorable outcome, patients with poor outcome had lower ΔSBP (less SBP reduction) at all times intervals. After adjusting for potential confounders including baseline SBP, both ΔSBP15-60M and ΔSBP6-24H were associated with lower odds of poor outcome (adjusted odds ratio per 5 mm Hg SBP reduction, 0.89 [95% CI, 0.81-0.99], and adjusted odds ratio 0.82 [95% CI, 0.73-0.92], respectively). Concerning safety outcomes, patients with intraparenchymal hemorrhage had lower ΔSBP at all time intervals. ΔSBP15-60M was associated with lower odds of any intraparenchymal hemorrhage (adjusted odds ratio per 5 mm Hg SBP reduction 0.91 [95% CI, 0.83-0.99]). Conversely, ΔSBP was not associated with mortality or neurological deterioration at any time interval. CONCLUSIONS After successful reperfusion, ΔSBP had a linear relationship with poor outcome and the risk of poor outcome was higher with less reduction from the baseline SBP. REGISTRATION URL: https://www.clinicaltrials.gov; Unique identifier: NCT03160677.
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Affiliation(s)
- Mohammad Anadani
- Department of Neurology, Washington University, St Louis, MO (M.A.).,Department of Neurosurgery, Medical University of South Carolina, Charleston (M.A.)
| | - Benjamin Maïer
- Department of Interventional Neuroradiology, Hôpital Fondation Ophtalmologique Adolphe de Rothschild, Paris, France (B.M., S.E., J.-P.D., R.B., M.P., M.M.).,University of Paris, France (B.M., J.-P.D., M.M.).,FHU Neurovasc, Paris, France (B.M., J.-P.D., R.B., M.P., M.M.)
| | - Simon Escalard
- Department of Interventional Neuroradiology, Hôpital Fondation Ophtalmologique Adolphe de Rothschild, Paris, France (B.M., S.E., J.-P.D., R.B., M.P., M.M.)
| | - Julien Labreuche
- University of Lille, CHU Lille, ULR 2694-METRICS: Évaluation des technologies de santé et des pratiques médicales, France (J.L.).,CHU Lille, Department of Biostatistics, France (J.L.)
| | - Adam de Havenon
- Department of Neurology, University of Utah, Salt Lake City (A.d.H.)
| | | | - Bertrand Lapergue
- Division of Neurology, Department of Neurology, Stroke Centre, Foch Hospital, University Versailles Saint-Quentin en Yvelines, Suresnes, France (B.L.)
| | - Benjamin Gory
- Department of Diagnostic and Therapeutic Neuroradiology, Nancy, France (B.G.).,Université de Lorraine, IADI, INSERM U1254, Nancy, France (B.G.)
| | | | | | - Jean-Philippe Desilles
- Department of Interventional Neuroradiology, Hôpital Fondation Ophtalmologique Adolphe de Rothschild, Paris, France (B.M., S.E., J.-P.D., R.B., M.P., M.M.).,University of Paris, France (B.M., J.-P.D., M.M.).,FHU Neurovasc, Paris, France (B.M., J.-P.D., R.B., M.P., M.M.)
| | - Raphael Blanc
- Department of Interventional Neuroradiology, Hôpital Fondation Ophtalmologique Adolphe de Rothschild, Paris, France (B.M., S.E., J.-P.D., R.B., M.P., M.M.).,FHU Neurovasc, Paris, France (B.M., J.-P.D., R.B., M.P., M.M.)
| | - Michel Piotin
- Department of Interventional Neuroradiology, Hôpital Fondation Ophtalmologique Adolphe de Rothschild, Paris, France (B.M., S.E., J.-P.D., R.B., M.P., M.M.).,FHU Neurovasc, Paris, France (B.M., J.-P.D., R.B., M.P., M.M.)
| | - Mikael Mazighi
- Department of Interventional Neuroradiology, Hôpital Fondation Ophtalmologique Adolphe de Rothschild, Paris, France (B.M., S.E., J.-P.D., R.B., M.P., M.M.).,University of Paris, France (B.M., J.-P.D., M.M.).,FHU Neurovasc, Paris, France (B.M., J.-P.D., R.B., M.P., M.M.)
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Anadani M, Matusevicius M, Tsivgoulis G, Peeters A, Nunes AP, Mancuso M, Roffe C, de Havenon A, Ahmed N. Magnitude of blood pressure change and clinical outcomes after thrombectomy in stroke caused by large artery occlusion. Eur J Neurol 2021; 28:1922-1930. [PMID: 33682232 DOI: 10.1111/ene.14807] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 02/28/2021] [Accepted: 03/02/2021] [Indexed: 12/16/2022]
Abstract
BACKGROUND Extremes of both high and low systolic blood pressure (SBP) after mechanical thrombectomy (MT) in large artery occlusion stroke are known predictors of unfavorable outcome. However, the effect of SBP change (∆SBP) during the first 24 h on thrombectomy outcomes remains unclear. We aimed to investigate the association between ∆SBP at different time intervals and thrombectomy outcomes. METHODS We analyzed MT-treated patients registered in the SITS International Stroke Thrombectomy Registry from January 1, 2014 to September 3, 2019. Primary outcome was 3-month unfavorable outcome (modified Rankin scale scores 3-6). We defined ∆SBP as the mean SBP of a given time interval after MT (0-2, 2-4, 4-12, 12-24 h) minus admission SBP. Multivariable mixed logistic regression models were used to adjust for known confounders and center as random effect. Subgroup analyses were included to contrast specific subpopulations. Restricted cubic splines were used to model the associations. RESULTS The study population consisted of 5835 patients (mean age 70 years, 51% male, median NIHSS 16). Mean ∆SBP was -12.3, -15.7, -17.2, and -16.9 mmHg for the time intervals 0-2, 2-4, 4-12 h, and 12-24 h, respectively. Higher ∆SBP was associated with unfavorable outcome at 0-2 h (odds ratio 1.065, 95% confidence interval 1.014-1.118), 2-4 h (1.140, 1.081-1.203), 4-12 h (1.145, 1.087-1.203), and 12-24 h (1.145, 1.089-1.203), for every increase of 10 mmHg. Restricted cubic spline models suggested that increasing ∆SBP was associated with unfavorable outcome, with higher values showing increased risk of unfavorable outcome. CONCLUSION SBP increase after thrombectomy in large artery occlusion stroke is associated with poor functional outcome.
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Affiliation(s)
- Mohammad Anadani
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA
| | - Marius Matusevicius
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Department of Research and Education, Karolinska University Hospital, Stockholm, Sweden
| | - Georgios Tsivgoulis
- Second Department of Neurology, National & Kapodistrian University of Athens, Athens, Greece
| | | | - Ana Paiva Nunes
- Stroke Unit Centro Hospitalar Universitário de Lisboa Central - Hospital São José, Lisbon, Portugal
| | - Michelangelo Mancuso
- Department of Clinical and Experimental Medicine, Neurological Clinic, University of Pisa and Azienda Ospedaliera Universitaria Pisana, Pisa, Italy
| | - Christine Roffe
- Stroke Research in Stoke, University Hospitals of North Midlands NHS Trust, Stoke-on-Trent, UK
| | - Adam de Havenon
- Department of Neurology, University of Utah, Salt Lake City, UT, USA
| | - Niaz Ahmed
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Department of Neurovascular Disease, Karolinska University Hospital, Stockholm, Sweden
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Kang BT, Leoni RF, Kim DE, Silva AC. Phenylephrine-induced hypertension during transient middle cerebral artery occlusion alleviates ischemic brain injury in spontaneously hypertensive rats. Brain Res 2012; 1477:83-91. [PMID: 22954904 PMCID: PMC3456967 DOI: 10.1016/j.brainres.2012.08.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 07/24/2012] [Accepted: 08/14/2012] [Indexed: 10/27/2022]
Abstract
Arterial hypertension is a major risk factor for ischemic stroke. However, the management of preexisting hypertension is still controversial in the treatment of acute stroke in hypertensive patients. The present study evaluates the influence of preserving hypertension during focal cerebral ischemia on stroke outcome in a rat model of chronic hypertension, the spontaneously hypertensive rats (SHR). Focal cerebral ischemia was induced by transient (1h) occlusion of the middle cerebral artery, during which mean arterial blood pressure was maintained at normotension (110-120mm Hg, group 1, n=6) or hypertension (160-170mm Hg, group 2, n=6) using phenylephrine. T2-, diffusion- and perfusion-weighted MRI were performed serially at five different time points: before and during ischemia, and at 1, 4 and 7 days after ischemia. Lesion volume and brain edema were estimated from apparent diffusion coefficient maps and T2-weighted images. Regional cerebral blood flow (rCBF) was measured within and outside the perfusion deficient lesion and in the corresponding regions of the contralesional hemisphere. Neurological deficits were evaluated after reperfusion. Infarct volume, edema, and neurological deficits were significantly reduced in group 2 vs. group 1. In addition, higher values and rapid restoration of rCBF were observed in group 2, while rCBF in both hemispheres was significantly decreased in group 1. Maintaining preexisting hypertension alleviates ischemic brain injury in SHR by increasing collateral circulation to the ischemic region and allowing rapid restoration of rCBF. The data suggest that maintaining preexisting hypertension is a valuable approach to managing hypertensive patients suffering from acute ischemic stroke.
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Affiliation(s)
- Byeong-Teck Kang
- Cerebral Microcirculation Unit, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
- Laboratory of Molecular Imaging and Translational Research, College of Veterinary Medicine, Chungbuk National University, Cheongju, South Korea
| | - Renata F. Leoni
- Cerebral Microcirculation Unit, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
- Department of Neuroscience and Behavioral Sciences, FMRP, University of Sao Paulo, Ribeirao Preto, Brazil
| | - Dong-Eog Kim
- Molecular Imaging and Neurovascular Research (MINER) Laboratory, Dongguk University Ilsan Hospital, Goyang, South Korea
| | - Afonso C. Silva
- Cerebral Microcirculation Unit, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
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Moldovan M, Constantinescu AO, Balseanu A, Oprescu N, Zagrean L, Popa-Wagner A. Sleep deprivation attenuates experimental stroke severity in rats. Exp Neurol 2010; 222:135-43. [PMID: 20045410 DOI: 10.1016/j.expneurol.2009.12.023] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2009] [Revised: 12/01/2009] [Accepted: 12/22/2009] [Indexed: 12/19/2022]
Abstract
Indirect epidemiological and experimental evidence suggest that the severity of injury during stroke is influenced by prior sleep history. The aim of our study was to test the effect of acute sleep deprivation on early outcome following experimental stroke. Young male Sprague-Dawley rats (n=20) were subjected to focal cerebral ischemia by reversible right middle cerebral artery occlusion (MCAO) for 90 min. In 10 rats, MCAO was performed just after 6-h of total sleep deprivation (TSD) by "gentle handling", whereas the other rats served as controls. Neurological function during the first week after stroke was monitored using a battery of behavioral tests investigating the asymmetry of sensorimotor deficit (tape removal test and cylinder test), bilateral sensorimotor coordination (rotor-rod and Inclined plane) and memory (T-maze and radial maze). Following MCAO, control rats had impaired behavioral performance in all tests. The largest impairment was noted in the tape test where the tape removal time from the left forelimb (contralateral to MCAO) was increased by approximately 10 fold (p<0.01). In contrast, rats subjected to TSD had complete recovery of sensorimotor performance consistent with a 2.5 fold smaller infarct volume and reduced morphological signs of neuronal injury at day 7 after MCAO. Our data suggest that brief TSD induces a neuroprotective response that limits the severity of a subsequent stroke, similar to rapid ischemic preconditioning.
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Affiliation(s)
- Mihai Moldovan
- Department of Physiology, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
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Gharbawie OA, Williams PTJA, Kolb B, Whishaw IQ. Transient middle cerebral artery occlusion disrupts the forelimb movement representations of rat motor cortex. Eur J Neurosci 2008; 28:951-63. [PMID: 18717732 DOI: 10.1111/j.1460-9568.2008.06399.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Infarcts from proximal middle cerebral artery (MCA) stroke can produce impairments in motor function, particularly finger movements in humans and digit flexion in rats. In rats, the extent of neural damage may be limited to basal ganglia structures or may also include portions of the frontal and parietal cortex in severe cases. Although the primary motor cortex (M1) is anatomically spared in proximal MCA occlusion, its functional integrity is suspect because even a small subcortical infarct can damage neural circuits linking M1 with basal ganglia, brainstem, and spinal cord. This motivated the present study to investigate the neurophysiological integrity of M1 after transient proximal MCA occlusion. Rats, preoperatively trained and non-preoperatively trained to reach for food, received extensive reach training/testing with the contralateral-to-lesion paw for several weeks after MCA occlusion. The forelimb movement representations were assayed from the ipsilateral-to-lesion M1 with intracortical microstimulation approximately 10 weeks after MCA occlusion. Digit flexion was impaired during food grasping in rats with relatively small subcortical infarcts and was completely abolished in rats that sustained at least moderate subcortical damage. Corresponding forelimb movement representations ranged from abnormally small to absent. The results suggest that ischemia in subcortical territories of the MCA does not spare the neurophysiological properties of M1 despite its apparent anatomical intactness, probably because of damage sustained to its descending fibers. Thus, M1 dysfunction contributes to the impairments that ensue from proximal MCA occlusion, even when the infarct is limited to subcortical regions.
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Affiliation(s)
- Omar A Gharbawie
- Department of Neuroscience, Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, Alberta, Canada
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Shin HK, Nishimura M, Jones PB, Ay H, Boas DA, Moskowitz MA, Ayata C. Mild induced hypertension improves blood flow and oxygen metabolism in transient focal cerebral ischemia. Stroke 2008; 39:1548-55. [PMID: 18340095 DOI: 10.1161/strokeaha.107.499483] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE In focal ischemic cortex, cerebral blood flow autoregulation is impaired, and perfusion passively follows blood pressure variations. Although it is generally agreed that profound hypotension is harmful in acute stroke, the hemodynamic and metabolic impact of increased blood pressure on the ischemic core and penumbra are less well understood. We, therefore, tested whether pharmacologically induced hypertension improves cerebral blood flow and metabolism and tissue outcome in acute stroke using optical imaging with high spatiotemporal resolution. METHODS Cerebral blood flow, oxyhemoglobin, and cerebral metabolic rate of oxygen were measured noninvasively using simultaneous multispectral reflectance imaging and laser speckle flowmetry during distal middle cerebral artery occlusion in mice. Hypertension was induced by phenylephrine infusion starting 10 or 60 minutes after ischemia to raise blood pressure by 30% for the duration of ischemia; control groups received saline infusion. RESULTS Mild induced hypertension rapidly increased cerebral blood flow, oxyhemoglobin, and cerebral metabolic rate of oxygen in both the core and penumbra and prevented the expansion of cerebral blood flow deficit during 1 hour distal middle cerebral artery occlusion. Induced hypertension also diminished the deleterious effects of periinfarct depolarizations on cerebral blood flow, oxyhemoglobin, and cerebral metabolic rate of oxygen without altering their frequency. Consistent with this, mild induced hypertension reduced infarct volume by 48% without exacerbating tissue swelling when measured 2 days after 1 hour transient distal middle cerebral artery occlusion. CONCLUSIONS Our data suggest that mild induced hypertension increases collateral cerebral blood flow and oxygenation and improves cerebral metabolic rate of oxygen in the core and penumbra, supporting its use as bridging therapy in acute ischemic stroke until arterial recanalization is achieved.
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Affiliation(s)
- Hwa Kyoung Shin
- Stroke and Neurovascular Regulation Laboratory, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
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Abstract
Although control of hypertension is established as an important factor in the primary and secondary prevention of stroke, management of blood pressure in the setting of acute ischemic stroke remains controversial. Given limited data, the general consensus is that there is no proven benefit to lowering blood pressure in the first hours to days after acute ischemic stroke. Instead, there is concern that relative hypotension may lead to worsening of cerebral ischemia. For many years, the use of blood pressure augmentation ("induced hypertension") has been studied in animal models and in humans as a means of maintaining or improving perfusion to ischemic brain tissue. This approach is now widely used in neurocritical care units to treat delayed neurological deficits after subarachnoid hemorrhage, but its use in ischemic stroke patients remains anecdotal. This article reviews the cerebral physiology, animal models and human studies of induced hypertension as a treatment for acute ischemic stroke. Although there has not been a large, randomized clinical trial of this treatment, the available clinical data suggests that induced hypertension can result in at least short-term neurological improvement, with an acceptable degree of safety.
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Affiliation(s)
- Robert J Wityk
- Johns Hopkins University School of Medicine, Cerebrovascular Division, Johns Hopkins Hospital, Baltimore, MD 21287, USA.
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Abstract
BACKGROUND Control of hypertension is a well-established goal of primary prevention of stroke, but management of blood pressure in patients with a previous stroke or in the setting of acute stroke is complicated by the effect blood pressure changes may have on cerebral perfusion. REVIEW SUMMARY For patients with previous transient ischemic attack or chronic stroke, blood pressure reduction appears to be a safe and important facet of the secondary prevention of recurrent stroke. Less information is available concerning blood pressure management in acute stroke. Current protocols require strict blood pressure control in patients who are treated with thrombolytic therapy, to reduce the risk of hemorrhagic complications. In patients presenting with acute intracerebral hemorrhage, blood pressure reduction does not appear to cause significant reduction of cerebral blood flow, but at this time there are no studies to determine if there is a clinical benefit of acute blood pressure reduction in these patients. Finally, blood pressure reduction is not routinely recommended in patients with acute ischemic stroke, as it may precipitate further cerebral ischemia. Preliminary studies suggest, in fact, that there may be a role in the future for blood pressure elevation in the treatment of patients with acute ischemic stroke. CONCLUSIONS Current data support the use of blood pressure reduction in the secondary prevention of stroke in patients with cerebrovascular disease. In the setting of acute stroke, however, data are limited and blood pressure management must be tailored to the specific clinical situation.
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Affiliation(s)
- Robert J Wityk
- From the Department of Neurology, Johns Hopkins University School of Medicine, Johns Hopkins Hospital, Baltimore, Maryland 21287, USA.
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Singhal AB, Lo EH, Dalkara T, Moskowitz MA. Advances in stroke neuroprotection: hyperoxia and beyond. Neuroimaging Clin N Am 2006; 15:697-720, xii-xiii. [PMID: 16360598 DOI: 10.1016/j.nic.2005.08.014] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Refinements in patient selection, improved methods of drug delivery, use of more clinically relevant animal stroke models, and the use of combination therapies that target the entire neurovascular unit make stroke neuroprotection an achievable goal. This article provides an overview of the major mechanisms of neuronal injury and the status of neuroprotective drug trials and reviews emerging strategies for treatment of acute ischemic stroke. Advances in the fields of stem cell transplantation, stroke recovery, molecular neuroimaging, genomics, and proteomics will provide new therapeutic avenues in the near future. These and other developments over the past decade raise expectations that successful stroke neuroprotection is imminent.
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Abstract
Control of hypertension is a well-established goal of primary stroke prevention. Management of blood pressure in patients during acute ischaemic stroke, however, is complicated by the need to maintain brain perfusion. Lowering blood pressure in the acute setting may avoid the deleterious effects of high blood pressure but may also lead to cerebral hypoperfusion and worsening of the ischaemic stroke. Little information is available from clinical trials concerning optimal blood pressure management in acute stroke. Current protocols of thrombolytic therapy require strict blood pressure control below certain prescribed limits; however, in most acute stroke patients not treated with thrombolysis, blood pressure reduction is not routinely recommended and guidelines for target blood pressures are difficult to justify. Preliminary studies, in fact, suggest that there may be a role for blood pressure elevation in the treatment of some patients with acute ischaemic stroke.
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Affiliation(s)
- Robert J Wityk
- Cerebrovascular Division, The Johns Hopkins Hospital, Phipps 126 B, Baltimore, MD 21287, USA.
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Yokoo N, Sheng H, Mixco J, Homi HM, Pearlstein RD, Warner DS. Intraischemic Nitrous Oxide Alters Neither Neurologic Nor Histologic Outcome: A Comparison with Dizocilpine. Anesth Analg 2004; 99:896-903. [PMID: 15333428 DOI: 10.1213/01.ane.0000132973.32387.8b] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
N-Methyl-D-aspartate receptor antagonism contributes to the anesthetic action of nitrous oxide (N(2)O). We examined the effects of the N-methyl-D-aspartate antagonists N(2)O and dizocilpine on outcome from filament occlusion of the middle cerebral artery (MCAO). Rats breathed 70% nitrogen/30% oxygen or 70% N(2)O/30% oxygen during MCAO. A third group breathed 70% nitrogen/30% oxygen and was given dizocilpine (0.25 mg/kg IV). After 75 min of MCAO, the rats recovered for 3 or 14 days. Pericranial temperature was maintained at 37.5 degrees C +/- 0.2 degrees C during ischemia and for 20 h postischemia. N(2)O did not alter neurologic scores at 3 days (N(2)O, 21 +/- 6; nitrogen, 22 +/- 8; P = 0.95; 0 = normal; 48 = maximal deficit; mean +/- sd; n = 15) or 14 days (N(2)O, 13 +/- 6; nitrogen, 12 +/- 6; P = 0.93; n = 15-16) postischemia. N(2)O had no effect on infarct size at 3 days (N(2)O, 162 +/- 45 mm(3); nitrogen, 162 +/- 61 mm(3); P > 0.99) or 14 days (N(2)O, 147 +/- 56 mm(3); nitrogen, 151 +/- 62 mm(3); P = 0.99) postischemia. Dizocilpine treatment caused smaller infarcts (3 days: 66 +/- 49 mm(3), P < 0.0001 versus nitrogen; 14 days: 84 +/- 50 mm(3), P < 0.006 versus nitrogen) and reduced the neurologic deficit (3 days: 10 +/- 10, P = 0.002 versus nitrogen; 14 days: 6 +/- 7, P = 0.006 versus nitrogen). N(2)O (70%) had no effect on either behavioral or histologic outcome from transient focal cerebral ischemia when compared with results in rats breathing 70% nitrogen. These results indicate that normobaric N(2)O does not alter the response of rat brain to a focal ischemic insult.
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Affiliation(s)
- Noriko Yokoo
- Departments of *Anesthesiology, ‡Surgery, and §Neurobiology, Duke University Medical Center; and †Duke University School of Medicine, Durham, North Carolina
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Schwarz S, Georgiadis D, Aschoff A, Schwab S. Effects of induced hypertension on intracranial pressure and flow velocities of the middle cerebral arteries in patients with large hemispheric stroke. Stroke 2002; 33:998-1004. [PMID: 11935051 DOI: 10.1161/01.str.0000014584.17714.2e] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Our aim was to prospectively evaluate the effects of induced arterial hypertension in patients with large ischemic stroke. METHODS A total of 47 monitoring sessions in 19 patients with acute, complete, or subtotal middle cerebral artery (MCA) territory stroke were performed. Intracranial pressure (ICP) was monitored using a parenchymal catheter. Mean arterial blood pressure (MAP), ICP, and peak mean flow velocity of the middle cerebral arteries (V(m)MCA) were continuously recorded. Patients with acute ICP crises were excluded. After obtaining baseline values, MAP was raised by an infusion of norepinephrine to reach an MAP increase of at least 10 mm Hg. After MAP had reached a peak plateau level, the norepinephrine infusion was stopped. RESULTS Baseline MAP was 83.6+/-1.6 mm Hg and rose to 108.9+/-2.0 mm Hg after infusion of norepinephrine. ICP slightly increased from 11.6+/-0.9 mm Hg to 11.8+/-0.9 mm Hg (P<0.05). Cerebral perfusion pressure rose from baseline 72.2+/-2 mm Hg to 97+/-1 mm Hg (P<0.0001). V(m)MCA was already higher on the affected side during baseline measurements. At maximum MAP levels, V(m)MCA rose by 25.5+/-5.5 cm/s on the affected side and by 8.6+/-1.6 cm/s on the contralateral side. CONCLUSIONS In patients with large hemispheric stroke without an acute ICP crisis, induced hypertension enhances cerebral perfusion pressure and augments the V(m)MCA(s), more so on the affected side. The ICP slightly increases; however, this is probably not clinically significant.
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Affiliation(s)
- Stefan Schwarz
- Department of Neurology, University of Heidelberg, Heidelberg, Germany.
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Smrcka M, Ogilvy CS, Crow RJ, Maynard KI, Kawamata T, Ames A. Induced hypertension improves regional blood flow and protects against infarction during focal ischemia: time course of changes in blood flow measured by laser Doppler imaging. Neurosurgery 1998; 42:617-24; discussion 624-5. [PMID: 9526996 DOI: 10.1097/00006123-199803000-00032] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVE To characterize changes in regional blood flow (rCBF) during and after a period of arterial occlusion and determine the effect on rCBF and on the extent of infarction when the mean arterial blood pressure is increased during the period of occlusion. METHODS rCBF in the middle cerebral artery (MCA) territory of rabbits was monitored using laser Doppler perfusion imaging before, during, and after a 1- or 2-hour period of MCA occlusion, and the size of the infarction was assessed by 2,3,5-triphenyltetrazolamine chloride staining after 2 hours of reperfusion. Test animals, the mean arterial blood pressure of which was increased by 65 mm Hg with intravenous phenylephrine during the ischemia, were compared with control animals that remained normotensive. The laser Doppler perfusion imager (Lisca Developments Co., Linköping, Sweden) scanned a 3-cm2 area of cortex with a resolution of 4 mm2 every 15 minutes. RESULTS MCA occlusion reduced rCBF to 71 +/- 2% of the control level (n = 24, P < 0.001). Hypertension (HTN) restored rCBF to 84 +/- 3% of the control level (n = 12, P < 0.01), but the HTN-induced improvement diminished with time, so that after 1 hour, there was no longer a significant difference between hypertensive and normotensive animals. HTN during the MCA occlusion caused a 97% reduction in infarct size (P < 0.05) in the animals subjected to 1 hour of occlusion but caused only a 45% reduction (P approximately 0.1) in the animals subjected to 2 hours of occlusion. CONCLUSION This study supports the use of HTN to minimize ischemic injury from short intervals of major intracranial vessel occlusion but fails to demonstrate protection when HTN is maintained during occlusions of more than 1 hour.
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Affiliation(s)
- M Smrcka
- Neurosurgical Service, Massachusetts General Hospital and Harvard Medical School, Boston 02114, USA
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15
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Rordorf G, Cramer SC, Efird JT, Schwamm LH, Buonanno F, Koroshetz WJ. Pharmacological elevation of blood pressure in acute stroke. Clinical effects and safety. Stroke 1997; 28:2133-8. [PMID: 9368553 DOI: 10.1161/01.str.28.11.2133] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND AND PURPOSE Lowering of blood pressure can adversely affect ischemic symptoms in acute stroke. The aim of our study was to determine whether induced hypertension in stroke is safe and to examine its effects on neurological deficits in patients presenting with acute cerebral ischemia. METHODS We retrospectively reviewed all patients admitted to our neurological intensive care unit with the diagnosis of ischemic stroke over a 2.5-year period. Thirty-three patients were not given a pressor agent (Ph- group), while 30 were treated with phenylephrine (Ph+ group) in an attempt to improve cerebral perfusion. RESULTS Baseline characteristics showed few differences between the Ph+ and Ph- groups. Intracerebral hemorrhage, brain edema, cardiac morbidity, and mortality were not increased in the Ph+ group. In 10 of 30 Ph+ patients, a systolic blood pressure threshold was identified below which ischemic deficits worsened and above which deficits improved. The mean threshold was 156 mm Hg (range, 120 to 190 mm Hg). The mean number of stenotic/occluded cerebral arteries was greater in those Ph+ patients with an identified clinical blood pressure threshold (mean, 2.1 per patient) than in Ph+ patients without a threshold (mean, 1.2 per patient; P < .05). CONCLUSIONS The results suggest that careful use of phenylephrine induced hypertension is not associated with an increase in morbidity or mortality in acute stroke. Although based on a retrospective analysis of clinical practice, this report suggests that a subset of patients, particularly those with multiple stenosis of cerebral arteries, may improve neurologically upon elevation of the blood pressure.
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Affiliation(s)
- G Rordorf
- Department of Neurology and Stroke Service, Massachusetts General Hospital, Boston 02114, USA.
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16
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Hosomi N, Tsuda Y, Ichihara SI, Kitadai M, Ohyama H, Matsuo H. Duration threshold of induced hypertension on cerebral blood flow, energy metabolism, and edema after transient forebrain ischemia in gerbils. J Cereb Blood Flow Metab 1996; 16:1224-9. [PMID: 8898695 DOI: 10.1097/00004647-199611000-00017] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We have investigated whether there is a duration threshold for the effects of phenylephrine-induced hypertension on CBF, brain energy metabolism, and cerebral parenchymal specific gravity (SG) following transient forebrain ischemia in gerbils. Sixty gerbils were randomly assigned to one of the four treatment groups: one control group and three groups subjected to an increase of 25 mm Hg in MABP induced by treatment, 30 min after reperfusion, with phenylephrine for 15 min, 30 min, or 60 min. The local CBF was measured continuously, and the SG was evaluated 120 min after reperfusion. Sequential changes in brain energy metabolism, as shown by the ratio of phosphocreatine to inorganic phosphate (Pi), the beta-ATP/Pi ratio, and intracellular pH, were also measured. The 15-min induced hypertension regimen was most suited to the recovery of brain energy metabolism, which was associated with an increase in local CBF and a decrease in cerebral edema. These results demonstrate that a suitable duration can be chosen to optimize the beneficial effects of phenylephrine-induced hypertension on ischemic brain injury following transient forebrain ischemia.
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Affiliation(s)
- N Hosomi
- Second Department of Internal Medicine, Kagawa Medical School, Japan
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Niiro M, Simon RP, Kadota K, Asakura T. Proximal branching patterns of middle cerebral artery (MCA) in rats and their influence on the infarct size produced by MCA occlusion. J Neurosci Methods 1996; 64:19-23. [PMID: 8869480 DOI: 10.1016/0165-0270(95)00058-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The branching patterns of the proximal middle cerebral artery (MCA) and their influence on the infarct size following MCA occlusion in rats were studied. In the proximal part from the level of the olfactory tract, the MCA most often presented one surface branch extending anteriorly, with a variable number of surface branches extending posteriorly. We classified the branching patterns of the posteriorly extending surface branches as follows: Type 1 (57.5%), one prominent proximal surface branch; Type 2 (30.2%), no prominent branch but two or more small surface branches; and Type 3 (12.3%), no surface branches with a visible junction with the MCA but surface branches probably arising from the internal carotid artery at the origin of the MCA. When the proximal surface branches (especially that in Type 1) remained uncoagulated, the infarct size in both the cortex and striatum was significantly reduced compared with that when coagulation was proximal to the most proximal surface branch. The reduction of cortical and striatal infarct sizes was particularly prominent in the posterior portion. To increase the infarct size and reduce variability, it is suggested that the MCA trunk should be coagulated from the origin to the rhinal fissure including the surface branches.
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Affiliation(s)
- M Niiro
- Department of Neurology, University of California at San Francisco, 94110, USA
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Zhu CZ, Auer RN. Graded hypotension and MCA occlusion duration: effect in transient focal ischemia. J Cereb Blood Flow Metab 1995; 15:980-8. [PMID: 7593359 DOI: 10.1038/jcbfm.1995.124] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The first 2 h of middle cerebral artery occlusion (MCAO) are likely critical in determining the final outcome in ischemic stroke. To study this early postischemic period, male Wistar rats (n = 161) were subjected to right MCAO with closely spaced step variations in both duration of MCAO and blood pressure (BP), using the intraluminal suture technique. Quantitative neuropathology was performed at 25 coronal planes of the brain after 1-week survival. Atrophy was measured as the difference between the two hemispheres and was added to cortical and striatal necrosis to obtain total tissue loss. Damage consistently increased monotonically with increasing duration of occlusion only when infarct size was expressed as percentage of the contralateral hemisphere, but not when expressed as mm3, because of variable tissue size. The results showed that already at 1 week, the quantity of tissue loss due to resorption and transsynaptic effects approached the quantity of geographically traceable necrosis in cortex and striatum. Minimum brain damage (5%) occurred after 60 min at a BP of 80 mm Hg, with almost no cortical necrosis. Damage was extremely sensitive to hypotension and MCAO duration. At a BP of 40 mm Hg, 60 min of MCAO produced 25% damage, accelerating every 20 min during the 2-h period studied. At BP 80 mm Hg, 120 min of MCAO produced the same damage as only 80 min of MCAO at BP 60 mm Hg. At 60-, 80-, 100-, and 120-min duration of MCAO, infarct size was significantly reduced with increasing BP.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- C Z Zhu
- Department of Pathology, Faculty of Medicine, University of Calgary, Alberta, Canada
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Ali Zirh T, Neemettin Pamir M, Memet Ozek M, Sav A, Onat F. A standardisable model of focal cerebral ischaemia innormotensive rats. J Clin Neurosci 1995; 2:245-51. [DOI: 10.1016/s0967-5868(95)80010-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/1995] [Accepted: 02/07/1995] [Indexed: 10/25/2022]
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Yang GY, Betz AL. Reperfusion-induced injury to the blood-brain barrier after middle cerebral artery occlusion in rats. Stroke 1994; 25:1658-64; discussion 1664-5. [PMID: 8042219 DOI: 10.1161/01.str.25.8.1658] [Citation(s) in RCA: 247] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND AND PURPOSE The integrity of the blood-brain barrier may play an important pathophysiological role during postischemic reperfusion. To determine the factors that lead to exacerbation of brain injury by reperfusion, we investigated changes in cerebral blood flow, blood-brain barrier permeability, edema formation, and infarction in permanent or temporary middle cerebral artery occlusion in rats and studied the relation between local cerebral blood flow and blood-brain barrier disruption. METHODS Middle cerebral artery occlusion was performed with the rat suture model, allowing either permanent (6 hours) or temporary occlusion (3 hours of occlusion and 3 hours of reperfusion). We measured brain water, ion contents, and infarct volumes and determined cerebral blood flow using laser Doppler flowmetry and blood-brain barrier permeability with [3H] alpha-aminoisobutyric acid. RESULTS During occlusion, cerebral blood flow was reduced to 7% to 15% (permanent) and 10% to 17% (temporary) of the baseline. During 3 hours of reperfusion, it returned to 47% to 80% (lateral cortex) and 78% to 98% (medial cortex) of the baseline. Compared with the contralateral hemisphere, the water content in the ischemic area increased in both permanent and temporary groups (P < .05, P < .01). Both infarct volume and blood-brain barrier disruption were greater in the reperfusion group compared with the permanent occlusion group (P < .05). Blood-brain barrier disruption correlated with cerebral blood flow during reperfusion (P < .05). CONCLUSIONS These findings demonstrate that brain infarct and blood-brain barrier disruption are exacerbated after reperfusion in this model of focal ischemia. Blood-brain barrier disruption may relate to the degree of cerebral blood flow recovery. Thus, although early reperfusion in focal ischemia may preserve penumbra tissue, late reperfusion may increase the tissue injury.
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Affiliation(s)
- G Y Yang
- Department of Surgery (Neurosurgery), University of Michigan Medical Center, Ann Arbor 48109-0532
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Cole DJ, Drummond JC, Patel PM, Marcantonio S. Effects of viscosity and oxygen content on cerebral blood flow in ischemic and normal rat brain. J Neurol Sci 1994; 124:15-20. [PMID: 7931415 DOI: 10.1016/0022-510x(94)90004-3] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The mechanism of hemodilution-induced increases in cerebral blood flow (CBF) was investigated. Hemodilution was achieved with a molecular hemoglobin solution (DCLHb) and albumin which have similar viscosities but different oxygen carrying capacities. Part A: CBF was assessed in rats after one of the following regimens: (1) control-hematocrit not manipulated, (2) 30/Alb-hematocrit decreased to 30% with albumin, (3) 30/DCLHb-hematocrit decreased to 30% with DCLHb, or (4) 16/Alb/DCLHb-hematocrit decreased to 30% with albumin and then 16% with DCLHb. For viscosity matched groups (30/Alb and 30/DCLHb), CBF was greater in animals with decreased oxygen content (30/Alb); while in oxygen content matched groups (30/Alb and 16/Alb/DCLHb), CBF was greater in animals with decreased viscosity (16/Alb/DCLHb) (p < 0.05). Part B: Middle cerebral artery occlusion was performed, hemodilution achieved as in Part A, and CBF determined. For viscosity matched groups (30/Alb and 30/DCLHb), CBF was less in rats with decreased oxygen content (30/Alb); while in oxygen content matched groups (30/Alb and 16/Alb/DCLHb), CBF was greater in animals with decreased viscosity (16/Alb/DCLHb) (p < 0.05). This data supports the premise, that in normal brain, both viscosity and oxygen content effect CBF; while in ischemic brain, a decrease in viscosity but not oxygen content increases CBF.
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Affiliation(s)
- D J Cole
- Department of Anesthesiology, Loma Linda University, CA 92354
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Cole DJ, Schell RM, Przybelski RJ, Drummond JC, Bradley K. Focal cerebral ischemia in rats: effect of hemodilution with alpha-alpha cross-linked hemoglobin on CBF. J Cereb Blood Flow Metab 1992; 12:971-6. [PMID: 1400651 DOI: 10.1038/jcbfm.1992.134] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Hemodilution has had limited success as a treatment of cerebral ischemia. When using a nonoxygen binding fluid, the therapeutic efficacy of hemodilution-induced increases in CBF are offset by concomitant decreases in oxygen content. The effect of hemodilution, with diaspirin alpha-alpha cross-linked hemoglobin (DCLHb), on CBF during middle cerebral artery occlusion was assessed. Rats were hemodiluted to one of the following hematocrits (Hct): (a) 44/Hct, (b) 37/Hct, (c) 30/Hct, (d) 23/Hct, (e) 16/Hct, or (f) 9/Hct. After 10 min of ischemia, CBF was determined with 14C-iodoantipyrine. Coronal brain sections were evaluated for areas with a CBF of 0-10 and 11-20 ml 100 g-1 min-1. In addition, oxygen delivery was calculated. In the center of the ischemic zone, both areas of low CBF were less in the 30/Hct, 23/Hct, and 16/Hct groups compared with the 44/Hct and 37/Hct groups; and both areas were less in the 9/Hct group compared with the other five groups (p < 0.05). For the hemisphere contralateral to occlusion, there was a direct correlation between hematocrit and oxygen delivery. However, for the hemisphere ipsilateral to occlusion, oxygen delivery increased as hematocrit decreased (44/Hct, 8.6 +/- 0.3 vs. 9/Hct, 13.6 +/- 0.4 [mean +/- SD, ml 100 g-1 min-1]). The results of this study support a hypothesis that hemodilution with DCLHb decreases the extent of focal cerebral ischemia.
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Affiliation(s)
- D J Cole
- Department of Anesthesiology, Loma Linda University, CA 92354
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