1
|
Zhou Z, Orchard SG, Nelson MR, Fravel MA, Ernst ME. Angiotensin Receptor Blockers and Cognition: a Scoping Review. Curr Hypertens Rep 2024; 26:1-19. [PMID: 37733162 PMCID: PMC10796582 DOI: 10.1007/s11906-023-01266-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/21/2023] [Indexed: 09/22/2023]
Abstract
PURPOSE OF REVIEW To provide an overview of the association between angiotensin II receptor blocker (ARB) use and cognitive outcomes. RECENT FINDINGS ARBs have previously shown greater neuroprotection compared to other anti-hypertensive classes. The benefits are primarily attributed to the ARB's effect on modulating the renin-angiotensin system via inhibiting the Ang II/AT1R pathway and activating the Ang II/AT2R, Ang IV/AT4R, and Ang-(1-7)/MasR pathways. These interactions are associated with pleiotropic neurocognitive benefits, including reduced β-amyloid accumulation and abnormal hyperphosphorylation of tau, ameliorated brain hypo-fusion, reduced neuroinflammation and synaptic dysfunction, better neurotoxin clearing, and blood-brain barrier function restoration. While ACEis also inhibit AT1R, they simultaneously lower Ang II and block the Ang II/AT2R and Ang IV/AT4R pathways that counterbalance the potential benefits. ARBs may be considered an adjunctive approach for neuroprotection. This preliminary evidence, coupled with their underlying mechanistic pathways, emphasizes the need for future long-term randomized trials to yield more definitive results.
Collapse
Affiliation(s)
- Zhen Zhou
- School of Public Health and Preventive Medicine, Monash University, 553 St Kilda Road, Melbourne, VIC, 3004, Australia.
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia.
| | - Suzanne G Orchard
- School of Public Health and Preventive Medicine, Monash University, 553 St Kilda Road, Melbourne, VIC, 3004, Australia
| | - Mark R Nelson
- Menzies Institute for Medical Research, University of Tasmania, Hobart, TAS, Australia
| | - Michelle A Fravel
- Department of Pharmacy Practice and Science, College of Pharmacy, The University of Iowa, Iowa, IA, USA
| | - Michael E Ernst
- Department of Pharmacy Practice and Science, College of Pharmacy, The University of Iowa, Iowa, IA, USA.
- Department of Family Medicine, Carver College of Medicine, 01291-A PFP, The University of Iowa, 200 Hawkins Dr, Iowa, IA, 52242, USA.
| |
Collapse
|
2
|
Hahn M, Hayani E, Bitar L, Gröschel S, Steffen F, Protopapa M, Othman A, Bittner S, Zipp F, Gröschel K, Uphaus T. Strict blood pressure control following thrombectomy is associated with neuronal injury and poor functional outcome. Ann Clin Transl Neurol 2023; 10:2255-2265. [PMID: 37743753 PMCID: PMC10723244 DOI: 10.1002/acn3.51909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 07/31/2023] [Accepted: 09/09/2023] [Indexed: 09/26/2023] Open
Abstract
OBJECTIVE Mechanical thrombectomy (MT) has become standard treatment in acute ischemic stroke due to large vessel occlusion (LVO). However, optimal blood pressure (BP) management following successful recanalization remains unclear. We aim to investigate the association of strictly achieving BP targets of ≤160/90 mmHg with the extent of neuronal loss and functional outcome. METHODS In patients prospectively enrolled in the Gutenberg-Stroke-Study (May 2018-November 2019), BP was measured half-hourly for 24 h following MT. Based on achieving BP target of ≤160/90 mmHg, patients with successful recanalization of LVO were divided into "low-BP" group (BP ≤ 160/90 mmHg) or "high-BP" group (BP > 160/90 mmHg). Neuronal loss was quantified by serum-based measurement of neurofilament light chain (sNfL) after three days. BP groups and association of BP parameters with sNfL were investigated by correlation analyses and multiple regression modeling. RESULTS Of 253 enrolled patients (mean age 73.1 ± 12.9 years, 53.4% female), 165 met inclusion criteria. 21.2% (n = 35) strictly achieved "low-BP" target. "low-BP" was associated with unfavorable functional outcome at 90-day follow-up (aOR [95%CI]: 5.88 [1.88-18.32], p = 0.002) and decreased health-related quality of life (mean EQ-5D-index 0.45 ± 0.28 vs 0.63 ± 0.31, p = 0.009). sNfL levels were increased in "low-BP" patients (median [IQR] 239.7 [168.4-303.4] vs 118.8 [52.5-220.5] pg/mL, p = 0.026). Hypotensive episodes were more frequent in the "low-BP" group (48.6% vs 29.2%, p = 0.031). sNfL level could identify patients who had experienced hypotensive episodes with high discriminative ability (AUC [95%CI]: 0.68 [0.56-0.78], p = 0.007). INTERPRETATION Strict BP control (≤160/90 mmHg) within 24 h following successful recanalization of LVO by MT is associated with increased neuronal injury, displayed by higher sNfL levels, and poorer functional outcome, potentially indicating hypotension-induced neuronal loss during post-MT phase.
Collapse
Affiliation(s)
- Marianne Hahn
- Department of Neurology and Focus Program Translational Neuroscience (FTN), Rhine main Neuroscience Network (rmn2)University Medical Center of the Johannes Gutenberg University MainzMainzGermany
| | - Eyad Hayani
- Department of Neurology and Focus Program Translational Neuroscience (FTN), Rhine main Neuroscience Network (rmn2)University Medical Center of the Johannes Gutenberg University MainzMainzGermany
| | - Lynn Bitar
- Department of Neurology and Focus Program Translational Neuroscience (FTN), Rhine main Neuroscience Network (rmn2)University Medical Center of the Johannes Gutenberg University MainzMainzGermany
| | - Sonja Gröschel
- Department of Neurology and Focus Program Translational Neuroscience (FTN), Rhine main Neuroscience Network (rmn2)University Medical Center of the Johannes Gutenberg University MainzMainzGermany
| | - Falk Steffen
- Department of Neurology and Focus Program Translational Neuroscience (FTN), Rhine main Neuroscience Network (rmn2)University Medical Center of the Johannes Gutenberg University MainzMainzGermany
| | - Maria Protopapa
- Department of Neurology and Focus Program Translational Neuroscience (FTN), Rhine main Neuroscience Network (rmn2)University Medical Center of the Johannes Gutenberg University MainzMainzGermany
| | - Ahmed Othman
- Department of NeuroradiologyUniversity Medical Center of the Johannes Gutenberg University MainzMainzGermany
| | - Stefan Bittner
- Department of Neurology and Focus Program Translational Neuroscience (FTN), Rhine main Neuroscience Network (rmn2)University Medical Center of the Johannes Gutenberg University MainzMainzGermany
| | - Frauke Zipp
- Department of Neurology and Focus Program Translational Neuroscience (FTN), Rhine main Neuroscience Network (rmn2)University Medical Center of the Johannes Gutenberg University MainzMainzGermany
| | - Klaus Gröschel
- Department of Neurology and Focus Program Translational Neuroscience (FTN), Rhine main Neuroscience Network (rmn2)University Medical Center of the Johannes Gutenberg University MainzMainzGermany
| | - Timo Uphaus
- Department of Neurology and Focus Program Translational Neuroscience (FTN), Rhine main Neuroscience Network (rmn2)University Medical Center of the Johannes Gutenberg University MainzMainzGermany
| |
Collapse
|
3
|
Li M, Pang M, Cui X, Wang Y, Jia S, Lu Z, Wang Y. Lesion patterns and mechanism analysis of acute contralateral ischemic stroke accompanying stenosis of unilateral extracranial internal carotid artery. Brain Behav 2023; 13:e3111. [PMID: 37287415 PMCID: PMC10498073 DOI: 10.1002/brb3.3111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 05/23/2023] [Accepted: 05/23/2023] [Indexed: 06/09/2023] Open
Abstract
BACKGROUND Previous studies on unilateral internal carotid artery occlusive disease have focused on the mechanisms of ipsilateral hemispheric stroke, and contralateral stroke is considered to be an accidental phenomenon. Little is known about the relationship between severe stenosis (including occlusion) of the unilateral extracranial segment of the internal carotid artery and contralateral cerebral stroke, and the infarct patterns and pathogenesis require further study. The purpose of this study was to investigate the clinical characteristics and pathogenesis of contralateral acute stroke with unilateral extracranial internal carotid artery stenosis (including occlusion). METHODS Thirty-four patients were enrolled in this study, and all patients underwent routine clinical evaluation, including medical history, physical examination, laboratory tests, and various imaging evaluations. The morphological characteristics of diffusion-weighted magnetic resonance imaging were applied to determine infarct patterns. The etiological classification was confirmed according to the TOAST classification. RESULTS There were six distinctive lesion patterns: small subcortical infarcts (six patients), large subcortical infarcts (one patient), diffuse infarcts (eight patients), multiple anterior circulation infarcts (eight patients), multiple posterior circulation infarcts (two patients), and multiple anterior and posterior circulation infarcts (nine patients). CONCLUSION Diffuse and multiple infarcts were the most common topographic patterns in ischemic stroke contralateral to internal carotid artery stenosis or occlusion. Hemodynamic impairment of the contralateral hemisphere due to hypoperfusion and blood theft is regarded as the basis of stroke occurrence. Low ischemic tolerance and embolism are the main causes of acute ischemic stroke.
Collapse
Affiliation(s)
- Mengxin Li
- Department of Neurology IIAffiliated Hospital of Weifang Medical UniversityWeifangShandongChina
| | - Meng Pang
- Department of Neurology IIAffiliated Hospital of Weifang Medical UniversityWeifangShandongChina
| | - Xiaomei Cui
- Department of Neurology IIAffiliated Hospital of Weifang Medical UniversityWeifangShandongChina
| | - Yuge Wang
- Department of NeurologyThe Third Affiliated Hospital of Sun Yat‐sen UniversityGuangzhouChina
| | - Shuai Jia
- Department of Neurology IIAffiliated Hospital of Weifang Medical UniversityWeifangShandongChina
| | - Zhengqi Lu
- Department of NeurologyThe Third Affiliated Hospital of Sun Yat‐sen UniversityGuangzhouChina
| | - Yanqiang Wang
- Department of Neurology IIAffiliated Hospital of Weifang Medical UniversityWeifangShandongChina
| |
Collapse
|
4
|
The utility of therapeutic hypothermia on cerebral autoregulation. JOURNAL OF INTENSIVE MEDICINE 2022; 3:27-37. [PMID: 36789361 PMCID: PMC9924009 DOI: 10.1016/j.jointm.2022.08.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 07/26/2022] [Accepted: 08/10/2022] [Indexed: 11/07/2022]
Abstract
Cerebral autoregulation (CA) dysfunction is a strong predictor of clinical outcome in patients with acute brain injury (ABI). CA dysfunction is a potential pathologic defect that may lead to secondary injury and worse functional outcomes. Early therapeutic hypothermia (TH) in patients with ABI is controversial. Many factors, including patient selection, timing, treatment depth, duration, and rewarming strategy, impact its clinical efficacy. Therefore, optimizing the benefit of TH is an important issue. This paper reviews the state of current research on the impact of TH on CA function, which may provide the basis and direction for CA-oriented target temperature management.
Collapse
|
5
|
Taha A, Bobi J, Dammers R, Dijkhuizen RM, Dreyer AY, van Es ACGM, Ferrara F, Gounis MJ, Nitzsche B, Platt S, Stoffel MH, Volovici V, Del Zoppo GJ, Duncker DJ, Dippel DWJ, Boltze J, van Beusekom HMM. Comparison of Large Animal Models for Acute Ischemic Stroke: Which Model to Use? Stroke 2022; 53:1411-1422. [PMID: 35164533 PMCID: PMC10962757 DOI: 10.1161/strokeaha.121.036050] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Translation of acute ischemic stroke research to the clinical setting remains limited over the last few decades with only one drug, recombinant tissue-type plasminogen activator, successfully completing the path from experimental study to clinical practice. To improve the selection of experimental treatments before testing in clinical studies, the use of large gyrencephalic animal models of acute ischemic stroke has been recommended. Currently, these models include, among others, dogs, swine, sheep, and nonhuman primates that closely emulate aspects of the human setting of brain ischemia and reperfusion. Species-specific characteristics, such as the cerebrovascular architecture or pathophysiology of thrombotic/ischemic processes, significantly influence the suitability of a model to address specific research questions. In this article, we review key characteristics of the main large animal models used in translational studies of acute ischemic stroke, regarding (1) anatomy and physiology of the cerebral vasculature, including brain morphology, coagulation characteristics, and immune function; (2) ischemic stroke modeling, including vessel occlusion approaches, reproducibility of infarct size, procedural complications, and functional outcome assessment; and (3) implementation aspects, including ethics, logistics, and costs. This review specifically aims to facilitate the selection of the appropriate large animal model for studies on acute ischemic stroke, based on specific research questions and large animal model characteristics.
Collapse
Affiliation(s)
- Aladdin Taha
- Division of Experimental Cardiology, Department of Cardiology (A.T., J.B., D.J.D., H.M.M.v.B.), Erasmus MC University Medical Center, Rotterdam, the Netherlands
- Department of Neurology, Stroke Center (A.T., D.W.J.D.), Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Joaquim Bobi
- Division of Experimental Cardiology, Department of Cardiology (A.T., J.B., D.J.D., H.M.M.v.B.), Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Ruben Dammers
- Department of Neurosurgery, Stroke Center (R.D., V.V.), Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Rick M Dijkhuizen
- Biomedical MR Imaging and Spectroscopy Group, Center for Image Sciences, University Medical Center Utrecht, Utrecht University, the Netherlands (R.M.D.)
| | - Antje Y Dreyer
- Max Planck Institute for Infection Biology, Campus Charité Mitte, Berlin, Germany (A.Y.D.)
| | - Adriaan C G M van Es
- Department of Radiology, Leiden University Medical Center, the Netherlands (A.C.G.M.v.E.)
| | - Fabienne Ferrara
- Fraunhofer Institute for Cell Therapy and Immunology, Leipzig, Germany (F.F.)
| | - Matthew J Gounis
- Department of Radiology, New England Center for Stroke Research, University of Massachusetts Medical School, Worcester (M.J.G.)
| | - Björn Nitzsche
- Institute of Anatomy, Faculty of Veterinary Medicine (B.N.), University of Leipzig, Germany
- Department of Nuclear Medicine (B.N.), University of Leipzig, Germany
| | - Simon Platt
- Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Georgia, Athens (S.P.)
| | - Michael H Stoffel
- Division of Veterinary Anatomy, Vetsuisse Faculty, University of Bern, Switzerland (M.H.S.)
| | - Victor Volovici
- Department of Neurosurgery, Stroke Center (R.D., V.V.), Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Gregory J Del Zoppo
- Division of Hematology (G.J.d.Z.), University of Washington School of Medicine, Seattle
- Department of Medicine (G.J.d.Z.), University of Washington School of Medicine, Seattle
- Department of Neurology (G.J.d.Z.), University of Washington School of Medicine, Seattle
| | - Dirk J Duncker
- Division of Experimental Cardiology, Department of Cardiology (A.T., J.B., D.J.D., H.M.M.v.B.), Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Diederik W J Dippel
- Department of Neurology, Stroke Center (A.T., D.W.J.D.), Erasmus MC University Medical Center, Rotterdam, the Netherlands
| | - Johannes Boltze
- School of Life Sciences, Faculty of Science, University of Warwick, Coventry, United Kingdom (J.B.)
| | - Heleen M M van Beusekom
- Division of Experimental Cardiology, Department of Cardiology (A.T., J.B., D.J.D., H.M.M.v.B.), Erasmus MC University Medical Center, Rotterdam, the Netherlands
| |
Collapse
|
6
|
Nogueira RC, Beishon L, Bor-Seng-Shu E, Panerai RB, Robinson TG. Cerebral Autoregulation in Ischemic Stroke: From Pathophysiology to Clinical Concepts. Brain Sci 2021; 11:511. [PMID: 33923721 PMCID: PMC8073938 DOI: 10.3390/brainsci11040511] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 04/02/2021] [Accepted: 04/09/2021] [Indexed: 11/17/2022] Open
Abstract
Ischemic stroke (IS) is one of the most impacting diseases in the world. In the last decades, new therapies have been introduced to improve outcomes after IS, most of them aiming for recanalization of the occluded vessel. However, despite this advance, there are still a large number of patients that remain disabled. One interesting possible therapeutic approach would be interventions guided by cerebral hemodynamic parameters such as dynamic cerebral autoregulation (dCA). Supportive hemodynamic therapies aiming to optimize perfusion in the ischemic area could protect the brain and may even extend the therapeutic window for reperfusion therapies. However, the knowledge of how to implement these therapies in the complex pathophysiology of brain ischemia is challenging and still not fully understood. This comprehensive review will focus on the state of the art in this promising area with emphasis on the following aspects: (1) pathophysiology of CA in the ischemic process; (2) methodology used to evaluate CA in IS; (3) CA studies in IS patients; (4) potential non-reperfusion therapies for IS patients based on the CA concept; and (5) the impact of common IS-associated comorbidities and phenotype on CA status. The review also points to the gaps existing in the current research to be further explored in future trials.
Collapse
Affiliation(s)
- Ricardo C. Nogueira
- Neurology Department, School of Medicine, Hospital das Clinicas, University of São Paulo, São Paulo 01246-904, Brazil;
- Department of Neurology, Hospital Nove de Julho, São Paulo 01409-002, Brazil
| | - Lucy Beishon
- Cerebral Haemodynamics in Ageing and Stroke Medicine Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester LE2 7LX, UK; (L.B.); (R.B.P.); (T.G.R.)
| | - Edson Bor-Seng-Shu
- Neurology Department, School of Medicine, Hospital das Clinicas, University of São Paulo, São Paulo 01246-904, Brazil;
| | - Ronney B. Panerai
- Cerebral Haemodynamics in Ageing and Stroke Medicine Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester LE2 7LX, UK; (L.B.); (R.B.P.); (T.G.R.)
- National Institute for Health Research (NIHR) Leicester Biomedical Research Centre, University of Leicester, Leicester LE5 4PW, UK
| | - Thompson G. Robinson
- Cerebral Haemodynamics in Ageing and Stroke Medicine Research Group, Department of Cardiovascular Sciences, University of Leicester, Leicester LE2 7LX, UK; (L.B.); (R.B.P.); (T.G.R.)
- National Institute for Health Research (NIHR) Leicester Biomedical Research Centre, University of Leicester, Leicester LE5 4PW, UK
| |
Collapse
|
7
|
Carvalho LB, Kramer S, Borschmann K, Chambers B, Thijs V, Bernhardt J. Cerebral haemodynamics with head position changes post-ischaemic stroke: A systematic review and meta-analysis. J Cereb Blood Flow Metab 2020; 40:271678X20922457. [PMID: 32404023 PMCID: PMC7786838 DOI: 10.1177/0271678x20922457] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 02/20/2020] [Accepted: 04/02/2020] [Indexed: 01/01/2023]
Abstract
The effects of upright postures on the cerebral circulation early post-ischaemic stroke are not fully understood. We conducted a systematic review and meta-analysis to investigate the effects of head positioning on cerebral haemodynamics assessed by imaging methods post-ischaemic stroke. Of the 21 studies included (n = 529), 15 used transcranial Doppler. Others used near-infrared, diffuse correlation spectroscopy and nuclear medicine modalities. Most tested head positions between 0° and 45°. Seventeen studies reported changes in CBF parameters (increase at lying-flat or decrease at more upright) in the ischaemic hemisphere with position change. However, great variability was found and risk of bias was high in many studies. Pooled data of two studies ≤24 h (n = 28) showed a mean increase in cerebral blood flow (CBF) velocity of 8.5 cm/s in the ischaemic middle cerebral artery (95%CI,-2.2-19.3) from 30° to 0°. The increase found ≤48 h (n = 50) was of 2.3 cm/s (95%CI,-4.6-9.2), while ≤7 days (n = 38) was of 8.4 cm/s (95%CI, 1.8-15). Few very early studies (≤2 days) tested head positions greater than 30° and were unable to provide information about the response of acute stroke patients to upright postures (sitting, standing). These postures are part of current clinical practice and knowledge on their effects on cerebral haemodynamics is required.
Collapse
Affiliation(s)
- Lilian B Carvalho
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Heidelberg, Australia
- NHMRC Centre for Research Excellence in Stroke Rehabilitation and Brain Recovery, Heidelberg, Australia
| | - Sharon Kramer
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Heidelberg, Australia
- NHMRC Centre for Research Excellence in Stroke Rehabilitation and Brain Recovery, Heidelberg, Australia
| | - Karen Borschmann
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Heidelberg, Australia
- NHMRC Centre for Research Excellence in Stroke Rehabilitation and Brain Recovery, Heidelberg, Australia
- St Vincent’s Hospital, Melbourne, Australia
| | - Brian Chambers
- Department of Neurology, Austin Health, Heidelberg, Australia
- Department of Medicine, University of Melbourne, Victoria, Australia
| | - Vincent Thijs
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Heidelberg, Australia
- Department of Neurology, Austin Health, Heidelberg, Australia
| | - Julie Bernhardt
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Heidelberg, Australia
- NHMRC Centre for Research Excellence in Stroke Rehabilitation and Brain Recovery, Heidelberg, Australia
| |
Collapse
|
8
|
Liu C, Shi L, Zhu W, Yang S, Sun P, Qin Y, Tang X, Zhang S, Yao Y, Wang Z, Zhu W, Wang D. Fiber Connectivity Density in Cerebral Small-Vessel Disease Patients With Mild Cognitive Impairment and Cerebral Small-Vessel Disease Patients With Normal Cognition. Front Neurosci 2020; 14:83. [PMID: 32116526 PMCID: PMC7028684 DOI: 10.3389/fnins.2020.00083] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 01/21/2020] [Indexed: 11/17/2022] Open
Abstract
Abnormal structural connectivity of cerebral small-vessel disease (CSVD) is associated with cognitive impairment. But the different characteristics of structural connectivity have not been elucidated in early CSVD patients. The current study aimed to investigate the potential differences of structural connectivity in CSVD patients with mild cognitive impairment (MCI) and CSVD patients with normal cognition. Twenty-two CSVD patients with MCI, 34 CSVD patients with normal cognition, and 35 controls, who were age, sex, and education matched underwent diffusion tensor imaging and high resolution T1-weighted imaging. Clinical characteristics, lacunar infarct volume, white matter hyperintensity (WMH) volume, and global atrophy were quantitatively evaluated. Maps of fiber connectivity density (FiCD) were constructed and compared across groups in vertex levels. Pearson correlation was used to estimate the imaging–clinical relationships with control of general characteristics. CSVD patients with MCI had higher lesion load of WMH and lacunar infarcts, and correspondingly lower global FiCD value than CSVD patients with normal cognition (P < 0.01). Lacunar infarct (r = −0.318, P < 0.01) and WMH (r = −0.400, P < 0.01), but not global atrophy, age, or sex, were significantly correlated with the global FiCD value. CSVD patients with normal cognition showed decreased FiCD value mainly in the prefrontal areas (P < 0.01 with Monte Carlo correction). Compared with CSVD patients with normal cognition, CSVD patients with MCI showed significantly decreased FiCD value in enlarged frontal and parietal areas (P < 0.01 with Monte Carlo correction). Inter-group comparisons showed regional enhanced impairment of connectivity density in CSVD patients with MCI in the left superior frontal gyrus, the left precuneus, and the orbital part of the right inferior frontal gyrus (P < 0.01 with Monte Carlo correction). Regional FiCD value of frontal and parietal areas was associated with the cognitive function (P < 0.01). In conclusion, cognitively normal CSVD patients already have disruptions of structural connectivity. The extent and intensity of connectivity disruptions in frontal and parietal areas may underlie the mechanism of cognitive impairment in CSVD. Fiber connectivity density measurements may be helpful for quantitative description of structural cortical connectivity.
Collapse
Affiliation(s)
- Chengxia Liu
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Lin Shi
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, China
| | - Wenhao Zhu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shiqi Yang
- Xianning Central Hospital, Xianning, China
| | - Pan Sun
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, China
| | - Yuanyuan Qin
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiangyu Tang
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Shun Zhang
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yihao Yao
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhenxiong Wang
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Wenzhen Zhu
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Defeng Wang
- Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Hong Kong, China
| |
Collapse
|
9
|
Marmarelis VZ, Shin DC, Oesterreich M, Mueller M. Quantification of dynamic cerebral autoregulation and CO 2 dynamic vasomotor reactivity impairment in essential hypertension. J Appl Physiol (1985) 2020; 128:397-409. [PMID: 31917625 DOI: 10.1152/japplphysiol.00620.2019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The study of dynamic cerebral autoregulation (DCA) in essential hypertension has received considerable attention because of its clinical importance. Several studies have examined the dynamic relationship between spontaneous beat-to-beat arterial blood pressure data and contemporaneous cerebral blood flow velocity measurements (obtained via transcranial Doppler at the middle cerebral arteries) in the form of a linear input-output model using transfer function analysis. This analysis is more reliable when the contemporaneous effects of changes in blood CO2 tension are also taken into account, because of the significant effects of CO2 dynamic vasomotor reactivity (DVR) upon cerebral flow. In this article, we extract such input-output predictive models from spontaneous time series hemodynamic data of 24 patients with essential hypertension and 20 normotensive control subjects under resting conditions, using the novel methodology of principal dynamic modes (PDMs) that achieves improved estimation accuracy over previous methods for relatively short and noisy data. The obtained data-based models are subsequently used to compute indexes and markers that quantify DCA and DVR in each subject or patient and therefore can be used to assess the effects of essential hypertension. These model-based DCA and DVR indexes were properly defined to capture the observed effects of DCA and VR and found to be significantly different (P < 0.05) in the hypertensive patients. We also found significant differences between patients and control subjects in the relative contribution of three PDMs to the model output prediction, a finding that offers the prospect of identifying the physiological mechanisms affected by essential hypertension when the PDMs are interpreted in terms of specific physiological mechanisms.NEW & NOTEWORTHY This article presents novel model-based methodology for obtaining diagnostic indexes of dynamic cerebral autoregulation and dynamic vasomotor reactivity in hypertension.
Collapse
Affiliation(s)
- Vasilis Z Marmarelis
- Biomedical Simulations Resource Center, University of Southern California, Los Angeles, California
| | - Dae C Shin
- Biomedical Simulations Resource Center, University of Southern California, Los Angeles, California
| | | | - Martin Mueller
- Neurocenter, Luzerner Kantonsspital, Lucerne, Switzerland
| |
Collapse
|
10
|
Robertson AD, Atwi S, Kostoglou K, Verhoeff NPLG, Oh PI, Mitsis GD, Marzolini S, MacIntosh BJ. Cerebrovascular Pulsatility During Rest and Exercise Reflects Hemodynamic Impairment in Stroke and Cerebral Small Vessel Disease. ULTRASOUND IN MEDICINE & BIOLOGY 2019; 45:3116-3127. [PMID: 31570171 DOI: 10.1016/j.ultrasmedbio.2019.08.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 07/24/2019] [Accepted: 08/28/2019] [Indexed: 06/10/2023]
Abstract
Although aerobic exercise is recommended as a core component of stroke rehabilitation, knowledge of acute cerebrovascular responses in patients is limited. This study tested the hypothesis that older adults with chronic stroke or cerebral small vessel disease (SVD) exhibit a greater increase in pulsatile hemodynamics during exercise compared with young and age-matched healthy adults. Middle cerebral artery blood flow velocity was acquired during 20 min of moderate intensity cycling in 51 participants from four groups (young, old, SVD and stroke). During rest, only the stroke group had a higher pulsatility index (PI) compared with the young group (1.02 ± 0.17 vs 0.83 ± 0.13; p = 0.038). During exercise, however, the SVD group exhibited a larger increase in PI (68 ± 20% relative to rest) than the young (47 ± 19%), old (45 ± 17%) and stroke (40 ± 25%) groups (p < 0.05, for each). The stress of aerobic exercise may reveal arterial dysfunction associated with latent and overt cerebrovascular disease.
Collapse
Affiliation(s)
- Andrew D Robertson
- Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, Ottawa, Ontario, Canada; Hurvitz Brain Sciences Program, Sunnybrook Research Institute, University of Toronto, Toronto, Ontario, Canada.
| | - Sarah Atwi
- Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, Ottawa, Ontario, Canada; Hurvitz Brain Sciences Program, Sunnybrook Research Institute, University of Toronto, Toronto, Ontario, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Kyriaki Kostoglou
- Department of Electrical, Computer and Software Engineering, McGill University, Montreal, Quebec, Canada
| | - Nicolaas Paul L G Verhoeff
- Department of Psychiatry, Division of Geriatric Psychiatry, University of Toronto, Toronto, Ontario, Canada; Sam and Ida Ross Memory Disorders Clinic, Baycrest Health Sciences, Toronto, Ontario, Canada
| | - Paul I Oh
- Toronto Rehab, University Health Network, Toronto Ontario, Canada; Peter Munk Cardiac Centre, University of Toronto, Toronto, Ontario, Canada
| | - Georgios D Mitsis
- Department of Bioengineering, McGill University, Montreal, Quebec, Canada
| | - Susan Marzolini
- Toronto Rehab, University Health Network, Toronto Ontario, Canada
| | - Bradley J MacIntosh
- Heart and Stroke Foundation Canadian Partnership for Stroke Recovery, Ottawa, Ontario, Canada; Hurvitz Brain Sciences Program, Sunnybrook Research Institute, University of Toronto, Toronto, Ontario, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| |
Collapse
|
11
|
Complexity-Based Measures of Heart Rate Dynamics in Older Adults Following Long- and Short-Term Tai Chi Training: Cross-sectional and Randomized Trial Studies. Sci Rep 2019; 9:7500. [PMID: 31097732 PMCID: PMC6522618 DOI: 10.1038/s41598-019-43602-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 04/27/2019] [Indexed: 12/19/2022] Open
Abstract
Measures characterizing the complexity of heart rate (HR) dynamics have been informative in predicting age- and disease-related decline in cardiovascular health, but few studies have evaluated whether mind-body exercise can impact HR complexity. This study evaluated the effects of long-term Tai Chi (TC) practice on the complexity of HR dynamics using an observational comparison of TC experts and age- and gender-matched TC-naïve individuals. Shorter-term effects of TC were assessed by randomly assigning TC-naïve participants to either TC group to receive six months of TC training or to a waitlist control group. 23 TC experts (age = 63.3 ± 8.0 y; 24.6 ± 12.0 y TC experience) and 52 TC-naïve (age = 64.3 ± 7.7 y) were enrolled. In cross-sectional analyses, TC experts had a higher overall complexity index (CI, p = 0.004) and higher entropy at multiple individual time scales (p < 0.05); these findings persisted in models accounting for age, gender, body mass index (BMI), and physical activity levels. Longitudinal changes in complexity index did not differ significantly following random assignment to six months of TC vs. a waitlist control; however, within the TC group, complexity at select time scales showed statistically non-significant trends toward increases. Our study supports that longer-term TC mind-body training may be associated with increased complexity of HR dynamics.
Collapse
|
12
|
Orebaugh S, Palmeri S, Lin C, YaDeau J. Daring discourse: is nerve block with sedation the safest anesthetic for beach chair position? Reg Anesth Pain Med 2019; 44:707-712. [PMID: 30928909 DOI: 10.1136/rapm-2018-100230] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Revised: 03/02/2019] [Accepted: 03/06/2019] [Indexed: 11/04/2022]
Affiliation(s)
- Steven Orebaugh
- Anaesthesiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Shawn Palmeri
- Anaesthesiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Charles Lin
- Anaesthesiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Jacques YaDeau
- Anesthesiology, Hospital for Special Surgery, Weill Cornell Medical College, New York City, New York, USA
| |
Collapse
|
13
|
|
14
|
Chi NF, Hu HH, Wang CY, Chan L, Peng CK, Novak V, Hu CJ. Dynamic Cerebral Autoregulation Is an Independent Functional Outcome Predictor of Mild Acute Ischemic Stroke. Stroke 2018; 49:2605-2611. [DOI: 10.1161/strokeaha.118.022481] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Nai-Fang Chi
- From the Graduate Institute of Clinical Medicine, College of Medicine (N.-F.C., C.-J.H.), Taipei Medical University, Taiwan
- Department of Neurology, School of Medicine, College of Medicine (N.-F.C., L.C., C.-J.H.), Taipei Medical University, Taiwan
- Department of Neurology, Shuang Ho Hospital (N.-F.C., H.H.H., L.C., C.-J.H.), Taipei Medical University, Taiwan
- Research Center of Cerebrovascular Disease Treatment, College of Medicine (N.-F.C., H.H.H., C.Y.W., L.C., C.-J.H.), Taipei Medical University, Taiwan
- Faculty of Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan (N.-F.C.)
| | - Han-Hwa Hu
- Department of Neurology, Shuang Ho Hospital (N.-F.C., H.H.H., L.C., C.-J.H.), Taipei Medical University, Taiwan
- Research Center of Cerebrovascular Disease Treatment, College of Medicine (N.-F.C., H.H.H., C.Y.W., L.C., C.-J.H.), Taipei Medical University, Taiwan
| | - Cheng-Yen Wang
- Research Center of Cerebrovascular Disease Treatment, College of Medicine (N.-F.C., H.H.H., C.Y.W., L.C., C.-J.H.), Taipei Medical University, Taiwan
| | - Lung Chan
- Department of Neurology, School of Medicine, College of Medicine (N.-F.C., L.C., C.-J.H.), Taipei Medical University, Taiwan
- Department of Neurology, Shuang Ho Hospital (N.-F.C., H.H.H., L.C., C.-J.H.), Taipei Medical University, Taiwan
- Research Center of Cerebrovascular Disease Treatment, College of Medicine (N.-F.C., H.H.H., C.Y.W., L.C., C.-J.H.), Taipei Medical University, Taiwan
| | - Chung-Kang Peng
- Division of Interdisciplinary Medicine and Biotechnology (C.-K.P.), Beth Israel Deaconess Medical Center, Boston, MA
| | - Vera Novak
- Departments of Neurology (V.N.), Beth Israel Deaconess Medical Center, Boston, MA
| | - Chaur-Jong Hu
- From the Graduate Institute of Clinical Medicine, College of Medicine (N.-F.C., C.-J.H.), Taipei Medical University, Taiwan
- Department of Neurology, School of Medicine, College of Medicine (N.-F.C., L.C., C.-J.H.), Taipei Medical University, Taiwan
- Department of Neurology, Shuang Ho Hospital (N.-F.C., H.H.H., L.C., C.-J.H.), Taipei Medical University, Taiwan
- Research Center of Cerebrovascular Disease Treatment, College of Medicine (N.-F.C., H.H.H., C.Y.W., L.C., C.-J.H.), Taipei Medical University, Taiwan
- Graduate Institute of Neural Regenerative Medicine, College of Medical Science and Technology (C.-J.H.), Taipei Medical University, Taiwan
| |
Collapse
|
15
|
Wei W, Karim HT, Lin C, Mizuno A, Andreescu C, Karp JF, Reynolds CF, Aizenstein HJ. Trajectories in Cerebral Blood Flow Following Antidepressant Treatment in Late-Life Depression: Support for the Vascular Depression Hypothesis. J Clin Psychiatry 2018; 79:18m12106. [PMID: 30358242 PMCID: PMC6419103 DOI: 10.4088/jcp.18m12106] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 04/28/2018] [Indexed: 01/09/2023]
Abstract
OBJECTIVE Studies have identified longitudinally that there exists an association between depression, cerebral blood flow (CBF), and white matter hyperintensities that are thought to be due to vascular pathologies in the brain. However, the changes in CBF, a measure that reflects cerebrovascular integrity, following pharmacotherapy are not well understood. In this study, we investigated the dynamic CBF changes over the course of antidepressant treatment and the association of these changes with depressive symptoms. METHODS We used pseudocontinuous arterial spin labeling to investigate CBF changes in a sample of older patients (≥ 50 years of age; N = 46; 29 female) with a DSM-IV diagnosis of major depressive disorder. Participants had 5 magnetic resonance imaging scans (at baseline, the day after receiving a placebo, the day after receiving a first dose of venlafaxine, a week after starting venlafaxine treatment, and at the end of trial [12 weeks]). Montgomery-Asberg Depression Rating Scale (MADRS) was used to evaluate depression severity and treatment outcome. We investigated the association between changes in depression severity with changes in voxel-wise CBF while adjusting for potential confounding factors. RESULTS Increased CBF in the middle and posterior cingulate between baseline and end of treatment was significantly associated with percent decrease in MADRS score, independent of sex and Mini-Mental State Examination score (5,000 permutations, cluster forming threshold P < .005, family-wise error P < .05). No significant effects were detected between baseline and other scans (ie, placebo, acute [single dose], or subacute [after a week]). CONCLUSIONS Regional CBF increases were associated with decreases in depressive symptoms. This observation is consistent with the vascular depression hypothesis in late-life depression. TRIAL REGISTRATION ClinicalTrials.gov identifiers: NCT00892047 and NCT01124188.
Collapse
Affiliation(s)
- Wenjing Wei
- The Third Xiangya Hospital of Central South University, Changsha, Hunan, China,University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America
| | - Helmet T. Karim
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Chemin Lin
- Department of Psychiatry, Keelung Chang Gung Memorial Hospital, Keelung, Taiwan,College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Akiko Mizuno
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Carmen Andreescu
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Jordan F. Karp
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Charles F. Reynolds
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Howard J. Aizenstein
- Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America,Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| |
Collapse
|
16
|
Zhang Q, Zhang N, Kang L, Hu G, Yan X, Ding X, Fu Q, Zhang YT, Zhao N, Gao J, Strangman GE. Technology Development for Simultaneous Wearable Monitoring of Cerebral Hemodynamics and Blood Pressure. IEEE J Biomed Health Inform 2018; 23:1952-1963. [PMID: 30334773 DOI: 10.1109/jbhi.2018.2876087] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
For many cerebrovascular diseases both blood pressure (BP) and hemodynamic changes are important clinical variables. In this paper, we describe the development of a novel approach to noninvasively and simultaneously monitor cerebral hemodynamics, BP, and other important parameters at high temporal resolution (250 Hz sampling rate). In this approach, cerebral hemodynamics are acquired using near infrared spectroscopy based sensors and algorithms, whereas continuous BP is acquired by superficial temporal artery tonometry with pulse transit time based drift correction. The sensors, monitoring system, and data analysis algorithms used in the prototype for this approach are reported in detail in this paper. Preliminary performance tests demonstrated that we were able to simultaneously and noninvasively record and reveal cerebral hemodynamics and BP during people's daily activity. As examples, we report dynamic cerebral hemodynamic and BP fluctuations during postural changes and micturition. These preliminary results demonstrate the feasibility of our approach, and its unique power in catching hemodynamics and BP fluctuations during transient symptoms (such as syncope) and revealing the dynamic features of related events.
Collapse
|
17
|
Sperna Weiland NH, Brevoord D, Jöbsis DA, de Beaumont EMFH, Evers V, Preckel B, Hollmann MW, van Dieren S, de Mol BAJM, Immink RV. Cerebral oxygenation during changes in vascular resistance and flow in patients on cardiopulmonary bypass - a physiological proof of concept study. Anaesthesia 2016; 72:49-56. [DOI: 10.1111/anae.13631] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/15/2016] [Indexed: 12/17/2022]
Affiliation(s)
- N. H. Sperna Weiland
- Department of Anaesthesiology; Academic Medical Center; Amsterdam The Netherlands
| | - D. Brevoord
- Department of Anaesthesiology; Academic Medical Center; Amsterdam The Netherlands
| | - D. A. Jöbsis
- Department of Anaesthesiology; Academic Medical Center; Amsterdam The Netherlands
| | | | - V. Evers
- Department of Anaesthesiology; Academic Medical Center; Amsterdam The Netherlands
| | - B. Preckel
- Department of Anaesthesiology; Academic Medical Center; Amsterdam The Netherlands
| | - M. W. Hollmann
- Department of Anaesthesiology; Academic Medical Center; Amsterdam The Netherlands
| | - S. van Dieren
- Department of Anaesthesiology; Academic Medical Center; Amsterdam The Netherlands
| | - B. A. J. M. de Mol
- Department of Cardiothoracic Surgery; Academic Medical Center; Amsterdam The Netherlands
| | - R. V. Immink
- Department of Anaesthesiology; Academic Medical Center; Amsterdam The Netherlands
- Laboratory for Clinical Cardiovascular Physiology; Department of Anatomy and Embryology; Academic Medical Center; Amsterdam The Netherlands
| |
Collapse
|
18
|
Fan C, Zhao Y, Yu Q, Yin W, Liu H, Lin J, Yang T, Fan M, Gesang L, Zhang J. Reversible Brain Abnormalities in People Without Signs of Mountain Sickness During High-Altitude Exposure. Sci Rep 2016; 6:33596. [PMID: 27633944 PMCID: PMC5025655 DOI: 10.1038/srep33596] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 08/30/2016] [Indexed: 01/23/2023] Open
Abstract
A large proportion of lowlanders ascending to high-altitude (HA) show no signs of mountain sickness. Whether their brains have indeed suffered from HA environment and the persistent sequelae after return to lowland remain unknown. Thirty-one sea-level college students, who had a 30-day teaching on Qinghai-Tibet plateau underwent MRI scans before, during, and two months after HA exposure. Brain volume, cortical structures, and white matter microstructure were measured. Besides, serum neuron-specific enolase (NSE), C-reactive protein, and interleukin-6 and neuropsychiatric behaviors were tested. After 30-day HA exposure, the gray and white matter volumes and cortical surface areas significantly increased, with cortical thicknesses and curvatures changed in a wide spread regions; Anisotropy decreased with diffusivities increased in multiple sites of white matter tracts. Two months after HA exposure, cortical measurements returned to basal level. However, increased anisotropy with decreased diffusivities was observed. Behaviors and serum inflammatory factor did not significant changed during three time-point tests. NSE significantly decreased during HA but increased after HA exposure. Results suggest brain swelling occurred in people without neurological signs at HA, but no negative sequelae in cortical structures and neuropsychiatric functions were left after the return to lowlands. Reoxygenation changed white matter microstructure.
Collapse
Affiliation(s)
- Cunxiu Fan
- Department of Physiology, Medical College of Xiamen University, Xiamen 361102, Fujian, China
| | - Yuhua Zhao
- Institute of high altitude medicine, Tibet Autonomous Region People's Hospital, Lasa 850000, Tibet Autonomous Region, China
| | - Qian Yu
- Department of Physiology, Medical College of Xiamen University, Xiamen 361102, Fujian, China
| | - Wu Yin
- Department of Radiology, Tibet Autonomous Region People's Hospital, Lasa 850000, Tibet Autonomous Region, China
| | - Haipeng Liu
- Department of Radiology, Tibet Autonomous Region People's Hospital, Lasa 850000, Tibet Autonomous Region, China
| | - Jianzhong Lin
- Magnetic Resonance Center, Zhongshan Hospital Xiamen University, Xiamen 361004, Fujian, China
| | - Tianhe Yang
- Magnetic Resonance Center, Zhongshan Hospital Xiamen University, Xiamen 361004, Fujian, China
| | - Ming Fan
- Department of Brain Protection and Plasticity, Institute of Basic Medical Sciences, Beijing 100850, China
| | - Luobu Gesang
- Institute of high altitude medicine, Tibet Autonomous Region People's Hospital, Lasa 850000, Tibet Autonomous Region, China
| | - Jiaxing Zhang
- Department of Physiology, Medical College of Xiamen University, Xiamen 361102, Fujian, China
| |
Collapse
|
19
|
Yeung EW, Place R, Gordish-Dressman H, Visich P, Hoffman E, Walker SO, Granger DA. Salivary latent trait cortisol (LTC): Relation to lipids, blood pressure, and body composition in middle childhood. Psychoneuroendocrinology 2016; 71:110-8. [PMID: 27262343 DOI: 10.1016/j.psyneuen.2016.05.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Revised: 05/13/2016] [Accepted: 05/13/2016] [Indexed: 10/21/2022]
Abstract
Adversity experienced early in life has the potential to influence physical health later in life. The stress-health relation may be partially explained by stress-related effects on cardiovascular risk factors. This study explored links between individual differences in trait-like variation in the activity of the hypothalamic-pituitary-adrenal (HPA) axis with cardiovascular risk factors in children. 474 children (M age=9.22years; 54% female; 83% Caucasian) were included in this study, in which cardiovascular risk was assessed using the following indices - triglycerides (TG), HDL-cholesterol (HDL-C), glucose (Glu); resting systolic and diastolic blood pressure, body mass index (BMI), waist-to-hip ratio, and % fat. Saliva samples were measured 3 times a day (waking, 30min post-waking and bedtime) over 3days (later assayed for cortisol). A latent trait cortisol (LTC) factor explained 43% of the variance in cortisol levels within and across days. Confirmatory factor analysis identified three cardiovascular risk factors: lipids (i.e., TG and HDL-C), blood pressure (i.e., systolic and diastolic), and body composition (i.e., BMI, Waist-to-hip ratio, and % fat). Lower salivary LTC was associated with higher lipids, higher blood pressure, and higher body composition. The findings further support the internal and external validity of the LTC construct, and may also advance our understanding of the link between interindividual differences in HPA axis activity and cardiovascular risk in middle childhood.
Collapse
Affiliation(s)
- Ellen W Yeung
- Department of Psychology, Arizona State University, Tempe, AZ 85287-3604, USA; Institute for Interdisciplinary Salivary Bioscience Research, University of California at Irvine, Irvine, CA 92697-7085, USA.
| | - Rebecca Place
- Department of Exercise and Sport Performance, University of New England, Biddeford, ME 04005, USA
| | - Heather Gordish-Dressman
- George Washington University School of Medicine, Children's National Medical Center, Washington, DC 20010, USA
| | - Paul Visich
- Department of Exercise and Sport Performance, University of New England, Biddeford, ME 04005, USA
| | - Eric Hoffman
- Research Center for Genetic Medicine, Children's National Medical Center, Washington, DC 20012, USA
| | - Sheila O Walker
- The Johns Hopkins University, Bloomberg School of Public Health, Baltimore, MD 21205, USA; The Johns Hopkins University School of Education, Baltimore, MD 21218, USA; Institute for Interdisciplinary Salivary Bioscience Research, University of California at Irvine, Irvine, CA 92697-7085, USA
| | - Douglas A Granger
- Department of Psychology, Arizona State University, Tempe, AZ 85287-3604, USA; The Johns Hopkins University, Bloomberg School of Public Health, Baltimore, MD 21205, USA; The Johns Hopkins University School of Nursing, Baltimore, MD 21205, USA; The Johns Hopkins University School of Medicine, Baltimore, MD 21218, USA; Institute for Interdisciplinary Salivary Bioscience Research, University of California at Irvine, Irvine, CA 92697-7085, USA
| |
Collapse
|
20
|
Kutlubaev MA, Akhmadeeva LR. [The early post-stroke mobilization]. VOPROSY KURORTOLOGII, FIZIOTERAPII, I LECHEBNOĬ FIZICHESKOĬ KULTURY 2015; 92:46-50. [PMID: 25876435 DOI: 10.17116/kurort2015146-50] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Early mobilization is an important prerequisite for the successful recovery after stroke. However, it is unclear at present how early mobilization should be started after stroke. Three randomized controlled trials were devoted to the comparison of the effectiveness and safety of very early (within the first day after stroke) and early (within two days after stroke) mobilization. The meta-analysis of the results of these studies did not reveal any advantages of very early mobilization over early mobilization. One randomized control study was designed to compare the consequences of mobilization within 3 and 7 days after stroke. It has demonstrated that earlier mobilization is associated with fewer complications and does not exert negative effect on cerebral haemodynamics. A number of observational studies confirmed the positive effect of early mobilization on the outcome of stroke. It is concluded that it may be justified to start mobilization on the second day after stroke provided there are no contraindications to such modality. The practicability of very early mobilization remains to be elucidated.
Collapse
Affiliation(s)
- M A Kutlubaev
- GBUZ 'Respublikanskaja klinicheskaja bol'nitsa im. G.G. Kuvatova', ul. Dostoevskogo, 132, Ufa, Rossijskaja Federatsija, 450005
| | - L R Akhmadeeva
- GBOU VPO 'Bashkirskij gosudarstvennyj meditsinskij universitet' Minzdrava Rossii, Ufa
| |
Collapse
|
21
|
Petersen NH, Ortega-Gutierrez S, Reccius A, Masurkar A, Huang A, Marshall RS. Dynamic cerebral autoregulation is transiently impaired for one week after large-vessel acute ischemic stroke. Cerebrovasc Dis 2015; 39:144-50. [PMID: 25661277 DOI: 10.1159/000368595] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Accepted: 09/23/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Dynamic cerebral autoregulation (DCA) is the continuous counterregulation of cerebral blood flow to fluctuations in blood pressure. DCA can become impaired after acute stroke, but it remains unclear to what extent and over what interval this occurs. METHODS We included 28 patients (NIHSS = 12 ± 6.5, age = 68.4 ± 17.1, 16F) with acute large-vessel ischemic stroke in the middle cerebral artery territory and 29 healthy controls (mean age 54.9 ± 9, 16F). DCA was assessed by simultaneous measurement of blood pressure together with blood flow velocities using finger plethysmography/arterial catheter and transcranial Doppler over three 10-minute recordings on days 0-2, 3-6 and ≥7 days after stroke. Transfer function analysis was applied to calculate average phase shift (PS) in the low frequency range (0.06-0.12 Hz). Less PS indicated poorer autoregulation. The affected side was compared with the unaffected side and controls. Univariate comparisons of data were performed using t tests at single time points, and generalized estimating equations with an exchangeable correlation matrix to examine the change in PS over time. RESULTS At mean 1.3 ± 0.5 days after stroke the average PS in the affected hemisphere was 29.6 ± 10.5 vs. 42.5 ± 13 degrees in the unaffected hemisphere (p = 0.004). At 4.1 ± 1 days, the PS in affected and unaffected hemisphere was 23.2 ± 19.1 vs. 41.7 ± 18.5 degrees, respectively (p = 0.003). At mean 9.75 ± 2.2 days stroke there was no difference between the affected and the unaffected hemisphere (53.2 ± 28.2 vs. 50.7 ± 29.2 degrees, p = 0.69). Control subjects had an average PS = 47.9 ± 16.8, significantly different from patients' affected hemisphere at the first two measurements (p = 0.001), but not the third (p = 0.37). The PS in controls remained unchanged on repeat testing after an average 19.1 days (48.4 ± 17.1, p = 0.61). Using the last recording as the reference, the average PS in the affected hemisphere was -23.54 (-44.1, -3) degrees lower on recording one (p = 0.025), and -31.6 (-56.1, -7.1) degrees lower on recording two (p < 0.011). Changes in the unaffected hemisphere over time were nonsignificant. DISCUSSION These data suggest that dynamic cerebral autoregulation is impaired in the affected hemisphere throughout the first week after large-vessel ischemic stroke, and then normalizes by week two. These findings may have important implications for acute blood pressure management after stroke.
Collapse
Affiliation(s)
- Nils H Petersen
- Department of Neurology, Columbia University, New York, N.Y., USA
| | | | | | | | | | | |
Collapse
|
22
|
Macko RF, Ivey FM, Forrester LW. Task-Oriented Aerobic Exercise in Chronic Hemiparetic Stroke: Training Protocols and Treatment Effects. Top Stroke Rehabil 2015; 12:45-57. [PMID: 15736000 DOI: 10.1310/pjqn-kan9-ttvy-hyqh] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Stroke is the leading cause of disability in older Americans. Each year 750,000 Americans suffer a stroke, two thirds of whom are left with neurological deficits that persistently impair function. Principal among them is hemiparetic gait that limits mobility and increases fall risk, promoting a sedentary lifestyle. These events propagate disability by physical deconditioning and "learned non-use," with further functional declines accelerated by the sarcopenia and fitness decrements of advancing age. Conventional rehabilitation care typically provides little or no structured therapeutic exercise beyond the subacute stroke recovery period, based on natural history studies showing little or no further functional motor recovery beyond 6 months after stroke. Emerging evidence suggests that new models of task-oriented exercise have the potential to improve motor function even years after stroke. This article presents treadmill as a task-oriented training paradigm to optimize locomotor relearning while eliciting cardiovascular conditioning in chronic stroke patients. Protocols for exercise testing and longitudinal aerobic training progression are presented that provide fundamental formulas that safely approach the complex task of customizing aerobic training to gait deficit severity in the high CVD risk stroke population. The beneficial effects of 6 months task-oriented treadmill exercise on cardiovascular-metabolic fitness, energy cost of hemiparetic gait, ADL mobility task performance, and leg strength are discussed with respect to the central and peripheral neuromuscular adaptations targeted by the training. Collectively, these findings constitute one initial experience in a much broader neuroscience and exercise rehabilitation development of task-oriented training paradigms that offer a multisystems approach to improving both neurological and cardiovascular health outcomes in the chronic stroke population.
Collapse
Affiliation(s)
- R F Macko
- Department of Neurology, Division of Gerontology, Baltimore Veterans Affairs Medical Center and University of Maryland School of Medicine, Baltimore, MD, USA
| | | | | |
Collapse
|
23
|
Arnoldussen IAC, Kiliaan AJ, Gustafson DR. Obesity and dementia: adipokines interact with the brain. Eur Neuropsychopharmacol 2014; 24:1982-99. [PMID: 24704273 PMCID: PMC4169761 DOI: 10.1016/j.euroneuro.2014.03.002] [Citation(s) in RCA: 152] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 03/11/2014] [Indexed: 12/20/2022]
Abstract
Obesity is a pandemic and a serious global health concern. Obesity is a risk factor for multiple conditions and contributes to multi-morbidities, resulting in increased health costs and millions of deaths each year. Obesity has been associated with changes in brain structure, cognitive deficits, dementia and Alzheimer׳s disease. Adipokines, defined as hormones, cytokines and peptides secreted by adipose tissue, may have more widespread influence and functionality in the brain than previously thought. In this review, six adipokines, and their actions in the obese and non-obese conditions will be discussed. Included are: plasminogen activator inhibitor-1 (PAI-1), interleukin-6 (IL-6), tumor necrosis factors alpha (TNF-α), angiotensinogen (AGT), adiponectin and leptin. Their functionality in the periphery, their ability to cross the blood brain barrier (BBB) and their influence on dementia processes within the brain will be discussed.
Collapse
Affiliation(s)
- Ilse A C Arnoldussen
- Department of Anatomy, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Centre, Geert Grooteplein Noord 21, 6525 EZ Nijmegen, The Netherlands.
| | - Amanda J Kiliaan
- Department of Anatomy, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Centre, Geert Grooteplein Noord 21, 6525 EZ Nijmegen, The Netherlands.
| | - Deborah R Gustafson
- Department of Neurology, State University of New York-Downstate Medical Center, 450 Clarkson Avenue, Box 1213, Brooklyn, NY11203, USA; UMS 011 Inserm Versailles Saint Quentin, France; Section for Psychiatry and Neurochemistry, Neuropsychiatric Epidemiology Unit, Sahlgrenska Academy at University of Gothenburg, Institute for Neuroscience and Physiology, NeuroPsychiatric Epidemiology Unit, Wallinsgatan 6, 431 41 Gothenburg, Sweden.
| |
Collapse
|
24
|
De Ciuceis C, Cornali C, Porteri E, Mardighian D, Pinardi C, Fontanella MM, Rodella LF, Rezzani R, Rizzoni D, Boari GEM, Rosei EA, Gasparotti R. Cerebral small-resistance artery structure and cerebral blood flow in normotensive subjects and hypertensive patients. Neuroradiology 2014; 56:1103-11. [PMID: 25204449 DOI: 10.1007/s00234-014-1423-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Accepted: 08/25/2014] [Indexed: 10/24/2022]
Abstract
INTRODUCTION The aim of this study was to prospectively investigate whether the structure of cerebral small-resistance arteries is related to cerebral perfusion parameters as measured with dynamic susceptibility-weighted contrast magnetic resonance imaging (DSC-MRI) in a selected cohort of hypertensive and normotensive patients. METHODS Ten hypertensive and 10 normotensive patients were included in the study. All patients underwent neurosurgical intervention for an intracranial tumor and were investigated with DSC-MRI at 1.5 T. Cerebral small-resistance arteries were dissected from a small portion of morphologically normal cerebral tissue and mounted on an isometric myograph for the measurement of the media-to-lumen (M/L) ratio. A quantitative assessment of cerebral blood flow (CBF) and volume (CBV) was performed with a region-of-interest approach. Correlation coefficients were calculated for normally distributed variables. The institutional review board approved the study, and informed consent was obtained from all patients. RESULTS Compared with normotensive subjects, hypertensive patients had significantly lower regional CBF (mL/100 g/min) in the cortical grey matter (55.63 ± 1.90 vs 58.37 ± 2.19, p < 0.05), basal ganglia (53.34 ± 4.39 vs 58.22. ± 4.33, p < 0.05), thalami (50.65 ± 3.23 vs 57.56 ± 4.45, p < 0.01), subcortical white matter (19.32 ± 2.54 vs 22.24 ± 1.9, p < 0.05), greater M/L ratio (0.099 ± 0.013 vs 0.085 ± 0.012, p < 0.05), and lower microvessel density (1.66 ± 0.67 vs 2.52 ± 1.28, p < 0.05). A statistically significant negative correlation was observed between M/L ratio of cerebral arteries and CBF in the cortical grey matter (r = -0.516, p < 0.05), basal ganglia (r = -0.521, p < 0.05), thalami (r = -0.527 p < 0.05), and subcortical white matter (r = -0.612, p < 0.01). CONCLUSION Our results indicate that microvascular structure might play a role in controlling CBF, with possible clinical consequences.
Collapse
Affiliation(s)
- Carolina De Ciuceis
- Clinica Medica, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Alosco ML, Gunstad J, Xu X, Clark US, Labbe DR, Riskin-Jones HH, Terrero G, Schwarz NF, Walsh EG, Poppas A, Cohen RA, Sweet LH. The impact of hypertension on cerebral perfusion and cortical thickness in older adults. ACTA ACUST UNITED AC 2014; 8:561-70. [PMID: 25151318 DOI: 10.1016/j.jash.2014.04.002] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 03/23/2014] [Accepted: 04/07/2014] [Indexed: 12/25/2022]
Abstract
Hypertension may increase risk for dementia possibly because of its association with decreased cortical thickness. Disturbed cerebral autoregulation is one plausible mechanism by which hypertension impacts the cerebral structure, but the associations among hypertension, brain perfusion, and cortical thickness are poorly understood. The current sample consisted of 58 older adults with varying levels of vascular disease. Diagnostic history of hypertension and antihypertensive medication status was ascertained through self-report, and when available, confirmed by medical record review. All participants underwent arterial spin labeling and T1-weighted magnetic resonance imaging to quantify total and regional cortical perfusion and thickness. Analysis of covariance adjusting for medical variables showed that participants with hypertension exhibited reduced temporal and occipital brain perfusion and total and regional cortical thickness relative to those without hypertension. The effects of hypertension on total brain perfusion remained unchanged even after adjustment for age, although no such pattern emerged for cortical thickness. Decreased total brain perfusion predicted reduced thickness of the total brain and of the frontal, temporal, and parietal lobe cortices. Antihypertensive treatment was not associated with total cerebral perfusion or cortical thickness. This study provides initial evidence for the adverse effects of a diagnostic history of hypertension on brain hypoperfusion and reduced cortical thickness. Longitudinal studies are needed to investigate the role of hypertension and its interaction with other contributing factors (e.g., age) in the manifestation of cerebral hypoperfusion and reduced cortical thickness.
Collapse
Affiliation(s)
| | - John Gunstad
- Department of Psychology, Kent State University, Kent, OH, USA
| | - Xiaomeng Xu
- Department of Psychology, Idaho State University, Pocatello, ID, USA
| | - Uraina S Clark
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Donald R Labbe
- Alpert Medical School of Brown University, the Department of Psychiatry and Human Behavior, Providence, RI, USA
| | - Hannah H Riskin-Jones
- Brain Behavior and Aging Research Center, VA Greater Los Angeles Healthcare System, Los Angeles, CA, USA
| | - Gretel Terrero
- Alpert Medical School of Brown University, Providence, RI, USA
| | | | - Edward G Walsh
- Brown University, Departments of Neuroscience and Diagnostic Imaging., Providence, RI, USA
| | - Athena Poppas
- Alpert Medical School of Brown University, Department of Medicine, Providence, RI, USA
| | - Ronald A Cohen
- Cognitive Aging and Memory Program, Clinical Translational Research Program, Institute on Aging, University of Florida, Gainesville, FL, USA
| | - Lawrence H Sweet
- Alpert Medical School of Brown University, the Department of Psychiatry and Human Behavior, Providence, RI, USA; Department of Psychology, University of Georgia, Athens, GA, USA
| |
Collapse
|
26
|
Abstract
Vascular cognitive impairment defines alterations in cognition, ranging from subtle deficits to full-blown dementia, attributable to cerebrovascular causes. Often coexisting with Alzheimer's disease, mixed vascular and neurodegenerative dementia has emerged as the leading cause of age-related cognitive impairment. Central to the disease mechanism is the crucial role that cerebral blood vessels play in brain health, not only for the delivery of oxygen and nutrients, but also for the trophic signaling that inextricably links the well-being of neurons and glia to that of cerebrovascular cells. This review will examine how vascular damage disrupts these vital homeostatic interactions, focusing on the hemispheric white matter, a region at heightened risk for vascular damage, and on the interplay between vascular factors and Alzheimer's disease. Finally, preventative and therapeutic prospects will be examined, highlighting the importance of midlife vascular risk factor control in the prevention of late-life dementia.
Collapse
Affiliation(s)
- Costantino Iadecola
- Brain and Mind Research Institute, Weill Cornell Medical College, New York, NY 10021, USA.
| |
Collapse
|
27
|
Tolerance of a standing tilt table protocol by patients an inpatient stroke unit setting: a pilot study. J Neurol Phys Ther 2013; 37:9-13. [PMID: 23399923 DOI: 10.1097/npt.0b013e318282a1f0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND AND PURPOSE To describe and examine physiologic and self-reported indices of tolerance to a standing tilt table protocol (STTP) among patients following an acute stroke. METHODS We undertook a prospective, observational pilot study of patients admitted to a stroke unit of a single academic medical center. A clinical protocol for the use of the tilt table was developed and applied to subjects in the acute phase following a stroke. The protocol involved a stepwise process to gradually raise the subject into a standing position on the tilt table platform, at 10° intervals from 60° to 90°. Tolerance of the STTP was operationally defined as the ability to sustain 60° or greater of tilt table inclination for a minimum of 5 minutes, without signs or symptoms of intolerance. Specific measures recorded were frequencies of the highest angle achieved, the duration of standing time tolerated, and physiologic response. RESULTS Thirty-six patients with ischemic or hemorrhagic stroke (22 women and 14 men) aged 24 to 87 (mean age = 62, SD = 16) years participated in a single trial of the STTP. Fifty-three percent of subjects (N = 19) attained 60° or higher on the tilt table, with a mean total standing time of approximately 9 minutes. DISCUSSION AND CONCLUSIONS This pilot study suggests that the use of a tilt table is well tolerated among patients in the acute stroke phase and may be an effective tool for introducing early upright mobilization to a medically fragile patient population.Video Abstract available (see Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A35) for more insights from the authors.
Collapse
|
28
|
Nagatani K, Nawashiro H, Takeuchi S, Otani N, Wada K, Shima K. Effects of a head-down tilt on cerebral blood flow in mice during bilateral common carotid artery occlusion. Asian J Neurosurg 2013; 7:171-3. [PMID: 23559983 PMCID: PMC3613638 DOI: 10.4103/1793-5482.106648] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Objectives: Data on the optimal head position for patients with acute ischemic stroke are unavailable. We evaluated the effects of mild head-down tilt (HDT) on cerebral blood flow (CBF) in mice during bilateral common carotid artery occlusion (BCCAO). Materials and Methods: We used mice with BCCAO (35 minutes) and divided these into 2 groups ( n=16): BCCAO at 0°-HDT and 5°-HDT. CBF was measured for both hemispheres with a non-invasive laser Doppler blood perfusion imager. Changes in CBF during BCCAO were examined in both groups. Results: A significantly greater increase in CBF in both hemispheres was observed in 5°-HDT mice than in 0°-HDT mice (126.1% (8.715)% vs. 102.1% (4.718)%; P=0.0294). Conclusion: HDT enhanced the increase in CBF in both hemispheres in the mouse BCCAO model. The potential mechanism underlying CBF increase enhanced by HDT during BCCAO warrants further investigation.
Collapse
Affiliation(s)
- Kimihiro Nagatani
- Department of Neurosurgery, National Defense Medical College, Saitama, Japan
| | | | | | | | | | | |
Collapse
|
29
|
Abstract
The relationship between cerebral hemodynamics and cognitive performance has increasingly become recognized as a major challenge in clinical practice for older adults. Both diabetes and hypertension worsen brain perfusion and are major risk factors for cerebrovascular disease, stroke and dementia. Cerebrovascular reserve has emerged as a potential biomarker for monitoring pressure-perfusion-cognition relationships. Endothelial dysfunction and inflammation, microvascular disease, and mascrovascular disease affect cerebral hemodynamics and play an important role in pathohysiology and severity of multiple medical conditions, presenting as cognitive decline in the old age. Therefore, the identification of cerebrovascular vascular reactivity as a new therapeutic target is needed for prevention of cognitive decline late in life.
Collapse
|
30
|
Pichiorri F, Vicenzini E, Gilio F, Giacomelli E, Frasca V, Cambieri C, Ceccanti M, Di Piero V, Inghilleri M. Effects of intermittent theta burst stimulation on cerebral blood flow and cerebral vasomotor reactivity. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2012; 31:1159-1167. [PMID: 22837279 DOI: 10.7863/jum.2012.31.8.1159] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
OBJECTIVES To determine whether intermittent theta burst stimulation influences cerebral hemodynamics, we investigated changes induced by intermittent theta burst stimulation on the middle cerebral artery cerebral blood flow velocity and vasomotor reactivity to carbon dioxide (CO(2)) in healthy participants. The middle cerebral artery flow velocity and vasomotor reactivity were monitored by continuous transcranial Doppler sonography. Changes in cortical excitability were tested by transcranial magnetic stimulation. METHODS In 11 healthy participants, before and immediately after delivering intermittent theta burst stimulation, we tested cortical excitability measured by the resting motor threshold and motor evoked potential amplitude over the stimulated hemisphere and vasomotor reactivity to CO(2) bilaterally. The blood flow velocity was monitored in both middle cerebral arteries throughout the experimental session. In a separate session, we tested the effects of sham stimulation under the same experimental conditions. RESULTS Whereas the resting motor threshold remained unchanged before and after stimulation, motor evoked potential amplitudes increased significantly (P = .04). During and after stimulation, middle cerebral artery blood flow velocities also remained bilaterally unchanged, whereas vasomotor reactivity to CO(2) increased bilaterally (P = .04). The sham stimulation left all variables unchanged. CONCLUSIONS The expected intermittent theta burst stimulation-induced changes in cortical excitability were not accompanied by changes in cerebral blood flow velocities; however, the bilateral increased vasomotor reactivity suggests that intermittent theta burst stimulation influences the cerebral microcirculation, possibly involving subcortical structures. These findings provide useful information on hemodynamic phenomena accompanying intermittent theta burst stimulation, which should be considered in research aimed at developing this noninvasive, low-intensity stimulation technique for safe therapeutic applications.
Collapse
Affiliation(s)
- Floriana Pichiorri
- Department of Neurology and Psychiatry, Sapienza University, Viale Dell'Università 30, 00185 Rome, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Diserens K, Moreira T, Hirt L, Faouzi M, Grujic J, Bieler G, Vuadens P, Michel P. Early mobilization out of bed after ischaemic stroke reduces severe complications but not cerebral blood flow: a randomized controlled pilot trial. Clin Rehabil 2011; 26:451-9. [DOI: 10.1177/0269215511425541] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Objective: To evaluate whether early mobilization after acute ischaemic stroke is better than delayed mobilization with regard to medical complications and if it is safe in relation to neurological function and cerebral blood flow. Design: Randomized controlled pilot trial of early versus delayed mobilization out of bed with incidence of severe complications as the primary outcome. Setting: Acute stroke unit in the neurology department of a University Hospital. Participants: Fifty patients after ischaemic stroke with a National Institutes of Health Stroke Scale (NIHSS) score >6 were recruited. Intervention: All patients were treated with physiotherapy immediately after their admission. In the early protocol patients were mobilized out of bed after 52 hours, in the delayed protocol after seven days. Results: Eight out of 50 randomized patients were excluded from the per-protocol analysis because of early transfer to other hospitals. There were 2 (8%) severe complications in the 25 early mobilization patients and 8 (47%) in the 17 delayed mobilization patients ( P < 0.006). There were no differences in the total number of complications or in clinical outcome. In the 26 patients (62%) who underwent serial transcranial Doppler ultrasonography, no blood flow differences were found. Conclusion: We found an apparent reduction in severe complications and no increase in total complications with an early mobilization protocol after acute ischaemic stroke. No influence on neurological three-month outcomes or on cerebral blood flow was seen. These results justify larger trials comparing mobilization protocols with possibly even faster mobilization out of bed than explored here.
Collapse
Affiliation(s)
- Karin Diserens
- Neurology Service, Department of Clinical Neurosciences, Centre Hospitalier Universitaire and University of Lausanne, Switzerland
| | - Tiago Moreira
- Neurology Service, Department of Clinical Neurosciences, Centre Hospitalier Universitaire and University of Lausanne, Switzerland
| | - Lorenz Hirt
- Neurology Service, Department of Clinical Neurosciences, Centre Hospitalier Universitaire and University of Lausanne, Switzerland
| | - Mohamed Faouzi
- Institute of Social and Preventive Medicine, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Switzerland
| | - Jelena Grujic
- Neurology Service, Department of Clinical Neurosciences, Centre Hospitalier Universitaire and University of Lausanne, Switzerland
| | - Gilles Bieler
- Medical Polyclinics, Centre Hospitalier Universitaire and University of Lausanne, Switzerland
| | | | - Patrik Michel
- Neurology Service, Department of Clinical Neurosciences, Centre Hospitalier Universitaire and University of Lausanne, Switzerland
| |
Collapse
|
32
|
|
33
|
Sanders RD, Degos V, Young WL. Cerebral perfusion under pressure: is the autoregulatory ‘plateau’ a level playing field for all? Anaesthesia 2011; 66:968-72. [DOI: 10.1111/j.1365-2044.2011.06915.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
34
|
Lee JY, Lee YS. Vasomotor reactivity in middle cerebral artery stenosis. J Neurol Sci 2011; 301:35-7. [PMID: 21112599 DOI: 10.1016/j.jns.2010.11.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2010] [Revised: 11/09/2010] [Accepted: 11/09/2010] [Indexed: 10/18/2022]
|
35
|
Abstract
The relationship between blood pressure (BP) and cognitive outcomes in elderly adults has implications for global health care. Both hypertension and hypotension affect brain perfusion and worsen cognitive outcomes. The presence of hypertension and other vascular risk factors has been associated with decreased performance in executive function and attention tests. Cerebrovascular reserve has emerged as a potential biomarker for monitoring pressure-perfusion-cognition relationships. A decline in vascular reserve capacity can lead to impaired neurovascular coupling and decreased cognitive ability. Endothelial dysfunction, microvascular disease, and mascrovascular disease in midlife could also have an important role in the manifestations and severity of multiple medical conditions underlying cognitive decline late in life. However, questions remain about the role of antihypertensive therapies for long-term prevention of cognitive decline. In this Review, we address the underlying pathophysiology and the existing evidence supporting the role of vascular factors in late-life cognitive decline.
Collapse
Affiliation(s)
- Vera Novak
- Division of Gerontology, Beth Israel Deaconess Medical Center and Harvard Medical School, 110 Francis Street, LMOB Suite 1b, Boston, MA 02215, USA.
| | | |
Collapse
|
36
|
Aries MJH, Elting JW, De Keyser J, Kremer BPH, Vroomen PCAJ. Cerebral autoregulation in stroke: a review of transcranial Doppler studies. Stroke 2010; 41:2697-704. [PMID: 20930158 DOI: 10.1161/strokeaha.110.594168] [Citation(s) in RCA: 229] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND PURPOSE Cerebral autoregulation may become impaired after stroke. To provide a review of the nature and extent of any autoregulation impairment after stroke and its course over time, a technique allowing repeated bedside measurements with good temporal resolution is required. Transcranial Doppler (TCD) in combination with continuous blood pressure measurements allows noninvasive continuous bedside investigation with high temporal resolution of the dynamic and the steady-state components of cerebral autoregulation. Therefore, this review focuses on all TCD studies on cerebral autoregulation in the setting of documented ischemic stroke. METHODS PubMed and EMBASE were searched for studies of stroke, autoregulation, and TCD. Studies were either acute phase (<96 hours after index stroke) or chronic phase (>96 hours after index stroke) autoregulation studies. Quality of studies was studied in a standardized fashion. RESULTS Twenty-three studies met the inclusion criteria. General agreement existed on cerebral autoregulation being impaired, even after minor stroke. Bilateral impairment of autoregulation was documented, particularly after lacunar stroke. Studies showed progressive deterioration of cerebral autoregulation in the first 5 days after stroke and recovery over the next 3 months. Impaired cerebral autoregulation as assessed by TCD was related to neurological deterioration, the necessity for decompressive surgery, and poor outcome. Synthesis of the data of various studies was, however, limited by studies not meeting key methodological criteria for observational studies. CONCLUSIONS TCD in combination with continuous blood pressure measurement offers a method with a high temporal resolution feasible for bedside evaluation of cerebral autoregulation in the stroke unit. TCD studies have shown impairment of cerebral autoregulation in various subtypes of ischemic stroke. To improve the synthesis of data from various research groups, there is urgent need for standardization of methodology of TCD studies in cerebral autoregulation.
Collapse
Affiliation(s)
- Marcel J H Aries
- University Medical Centre Groningen, Department of Neurology, Hanzeplein 1 9700 RB, Groningen, The Netherlands.
| | | | | | | | | |
Collapse
|
37
|
Hu K, Lo MT, Peng CK, Novak V, Schmidt EA, Kumar A, Czosnyka M. Nonlinear pressure-flow relationship is able to detect asymmetry of brain blood circulation associated with midline shift. J Neurotrauma 2009; 26:227-33. [PMID: 19196074 DOI: 10.1089/neu.2008.0643] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Reliable and noninvasive assessment of cerebral blood flow regulation is a major challenge in acute care monitoring. This study assessed dynamics of flow regulation and its relationship to asymmetry of initial computed tomography (CT) scan using multimodal pressure flow (MMPF) analysis. Data of 27 patients (38 +/- 15 years old) with traumatic brain injury (TBI) were analyzed. Patients were selected from bigger cohort according to criteria of having midline shift on initial CT scan and intact skull (no craniotomy or bone flap). The MMPF analysis was used to extract the oscillations in cerebral perfusion pressure (CPP) and blood flow velocity (BFV) signals at frequency of artificial ventilation, and to calculate the instantaneous phase difference between CPP and BFV oscillations. Mean CPP-BFV phase difference was used to quantify pressure and flow relationship. The TBI subjects had smaller mean BP-BFV phase shifts (left, 8.7 +/- 9.6; right 10.2 +/- 8.3 MCAs, mean +/- SD) than values previously obtained in healthy subjects (left, 37.3 +/- 7.6 degrees; right, 38.0 +/- 8.9 degrees; p < 0.0001), suggesting impaired blood flow regulation after TBI. The difference in phase shift between CPP and BFV in the left and right side was strongly correlated to the midline shift (R = 0.78; p < 0.0001). These findings indicate that the MMPF method allows reliable assessment of alterations in pressure and flow relationship after TBI. Moreover, mean pressure-flow phase shift is sensitive to the displacement of midline of the brain, and may potentially serve as a marker of asymmetry of cerebral autoregulation.
Collapse
Affiliation(s)
- Kun Hu
- Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA.
| | | | | | | | | | | | | |
Collapse
|
38
|
Novak V, Hu K, Desrochers L, Novak P, Caplan L, Lipsitz L, Selim M. Cerebral flow velocities during daily activities depend on blood pressure in patients with chronic ischemic infarctions. Stroke 2009; 41:61-6. [PMID: 19959536 DOI: 10.1161/strokeaha.109.565556] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Target blood pressure (BP) values for optimal cerebral perfusion after an ischemic stroke are still debated. We sought to examine the relationship between BP and cerebral blood flow velocities (BFVs) during daily activities. METHODS We studied 43 patients with chronic large vessel ischemic infarctions in the middle cerebral artery territory (aged 64.2+/-8.94 years; at 6.1+/-4.9 years after stroke) and 67 age-matched control subjects. BFVs in middle cerebral arteries were measured during supine baseline, sitting, standing, and tilt. A regression analysis and a dynamic phase analysis were used to quantify the BP-BFV relationship. RESULTS The mean arterial pressure was similar between the groups (89+/-15 mm Hg). Baseline BFVs were lower by approximately 30% in the patients with stroke compared with the control subjects (P=0.0001). BFV declined further with postural changes and remained lower in the stroke group during sitting (P=0.003), standing (P=0.003), and tilt (P=0.002) as compared with the control group. Average BFVs on the stroke side were positively correlated with BP during baseline (R=0.54, P=0.0022, the slope 0.46 cm/s/mm Hg) and tilt (R=0.52, P=0.0028, the slope 0.40 cm/s/mm Hg). Regression analysis suggested that BFV may increase approximately 30% to 50% at mean BP >100 mm Hg. Orthostatic hypotension during the first minute of tilt or standing was independently associated with lower BFV on the stroke side (P=0.0008). Baseline BP-BFV phase shift derived from the phase analysis was smaller on the stroke side (P=0.0006). CONCLUSIONS We found that BFVs are lower in patients with stroke and daily activities such as standing could induce hypoperfusion. BFVs increase with mean arterial pressure >100 mm Hg. Dependency of BFV on arterial pressure may have implications for BP management after stroke. Further prospective investigations are needed to determine the impact of these findings on functional recovery and strategies to improve perfusion pressure during daily activities after ischemic stroke.
Collapse
Affiliation(s)
- Vera Novak
- Division of Gerontology, Beth Israel Deaconess Medical Center, 110 Francis Street, Boston, MA 02215, USA.
| | | | | | | | | | | | | |
Collapse
|
39
|
Treger I, Luzki L, Gil M, Ring H. Transcranial doppler monitoring during language tasks in stroke patients with aphasia. Disabil Rehabil 2009; 29:1177-83. [PMID: 17653991 DOI: 10.1080/09638280600999493] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE To investigate the pattern of hemispheric activation, according to cerebral blood flow changes, as measured by Transcranial Doppler Ultrasonography (TCD) during language tasks in stroke patients with aphasia. METHOD Prospective study investigating results of TCD monitoring during language naming and recognition tasks in ischemic stroke patients (n = 32) with and without aphasia and 5 control subjects. RESULTS Delta mean flow velocity (MFV) in the left Middle Cerebral Artery (MCA) was found to be much lower in aphasia patients as compared to healthy subjects. Negative statistical correlation was found between the improvement of language ability and the blood flow velocity parameters in the left hemisphere. Aphasia patients with good language ability showed much higher MFV in the right MCA during the first test. Left hemispheric blood flow velocity shift was found to be higher during speech tasks in the patients with poor language ability. CONCLUSIONS Our study suggests that the performance of language tasks in aphasia patients during early recovery after stroke is associated with relatively high right hemisphere activation. High blood flow velocity in the right MCA of aphasia patients was found to be a good prognostic sign for better language ability. Arterial blood flow that shifted towards the left hemisphere during speech tasks was associated with poor language ability.
Collapse
Affiliation(s)
- I Treger
- Loewenstein Rehabilitation Hospital, Ra'anana, Israel
| | | | | | | |
Collapse
|
40
|
Treger I, Luzki L, Gil M, Ring H. Transcranial Doppler monitoring during language tasks in stroke patients with aphasia (response to letter to the editor). Disabil Rehabil 2009. [DOI: 10.1080/09638280701791344] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
41
|
Hu K, Peng CK, Czosnyka M, Zhao P, Novak V. Nonlinear assessment of cerebral autoregulation from spontaneous blood pressure and cerebral blood flow fluctuations. ACTA ACUST UNITED AC 2009; 8:60-71. [PMID: 18080758 DOI: 10.1007/s10558-007-9045-5] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Cerebral autoregulation (CA) is an most important mechanism responsible for the relatively constant blood flow supply to brain when cerebral perfusion pressure varies. Its assessment in nonacute cases has been relied on the quantification of the relationship between noninvasive beat-to-beat blood pressure (BP) and blood flow velocity (BFV). To overcome the nonstationary nature of physiological signals such as BP and BFV, a computational method called multimodal pressure-flow (MMPF) analysis was recently developed to study the nonlinear BP-BFV relationship during the Valsalva maneuver (VM). The present study aimed to determine (i) whether this method can estimate autoregulation from spontaneous BP and BFV fluctuations during baseline rest conditions; (ii) whether there is any difference between the MMPF measures of autoregulation based on intra-arterial BP (ABP) and based on cerebral perfusion pressure (CPP); and (iii) whether the MMPF method provides reproducible and reliable measure for noninvasive assessment of autoregulation. To achieve these aims, we analyzed data from existing databases including: (i) ABP and BFV of 12 healthy control, 10 hypertensive, and 10 stroke subjects during baseline resting conditions and during the Valsalva maneuver, and (ii) ABP, CPP, and BFV of 30 patients with traumatic brain injury (TBI) who were being paralyzed, sedated, and ventilated. We showed that autoregulation in healthy control subjects can be characterized by specific phase shifts between BP and BFV oscillations during the Valsalva maneuver, and the BP-BFV phase shifts were reduced in hypertensive and stroke subjects (P < 0.01), indicating impaired autoregulation. Similar results were found during baseline condition from spontaneous BP and BFV oscillations. The BP-BFV phase shifts obtained during baseline and during VM were highly correlated (R > 0.8, P < 0.0001), showing no statistical difference (paired-t test P > 0.47). In TBI patients there were strong correlations between phases of ABP and CPP oscillations (R = 0.99, P < 0.0001) and, thus, between ABP-BFV and CPP-BFV phase shifts (P < 0.0001, R = 0.76). By repeating the MMPF 4 times on data of TBI subjects, each time on a selected cycle of spontaneous BP and BFV oscillations, we showed that MMPF had better reproducibility than traditional autoregulation index. These results indicate that the MMPF method, based on instantaneous phase relationships between cerebral blood flow velocity and peripheral blood pressure, has better performance than the traditional standard method, and can reliably assess cerebral autoregulation dynamics from ambulatory blood pressure and cerebral blood flow during supine rest conditions.
Collapse
Affiliation(s)
- Kun Hu
- Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, 812 Stoneman Bldg, 330 Brookline Avenue, Boston, MA 02115, USA.
| | | | | | | | | |
Collapse
|
42
|
KUNZ ALEXANDER, IADECOLA COSTANTINO. Cerebral vascular dysregulation in the ischemic brain. HANDBOOK OF CLINICAL NEUROLOGY 2009; 92:283-305. [PMID: 18790280 PMCID: PMC3982865 DOI: 10.1016/s0072-9752(08)01914-3] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
43
|
Abstract
The human costs of stroke are very large and growing; it is the third largest cause of death in the United States and survivors are often faced with loss of ability to function independently. There is a large need for therapeutic approaches that act to protect neurons from the injury produced by ischemia and reperfusion. The goal of this review is to introduce and discuss the available data that endogenous cannabinoid signaling is altered during ischemia and that it contributes to the consequences of ischemia-induced injury. Overall, the available data suggest that inhibition of CB1 receptor activation together with increased CB2 receptor activation produces beneficial effects.
Collapse
Affiliation(s)
- Cecilia J Hillard
- Department of Pharmacology and Toxicology, Medical College of Wisconsin; Milwaukee, WI 53226, USA.
| |
Collapse
|
44
|
Hemispheric differences in cerebral autoregulation in children with moderate and severe traumatic brain injury. Neurocrit Care 2008; 9:45-54. [PMID: 18084727 DOI: 10.1007/s12028-007-9036-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
INTRODUCTION To examine hemispheric differences in cerebral autoregulation in children with traumatic brain injury (TBI). After IRB approval and consent, subjects underwent static cerebral autoregulation testing during the first 9 days after PICU admission. Cerebral autoregulation was quantified using the autoregulatory index (ARI). RESULTS Forty-two (27 M:15 F) children (10 +/- 5 years) with TBI and admission Glasgow coma scale score (5 +/- 2) were enrolled. Seven (54%) of the 13 children with focal TBI and 8 (28%) of 29 children with diffuse TBI had impairment or absence of cerebral autoregulation of at least one hemisphere. In patients with isolated focal TBI, ARI was lower (0.40 +/- 0.40 vs. 0.67 +/- 0.40; P = 0.03) in the side of TBI than in the unaffected hemisphere, but cerebral autoregulation was often impaired on the side without TBI or shift (5/13) on head CT. There was no difference in ARI between hemispheres in children with diffuse TBI, with or without superimposed focal lesions (P = 0.17). Patients with bilateral intact cerebral autoregulation tended to have higher 6 month Glasgow Outcome Score (GOS) than patients with either unilateral or bilateral cerebral autoregulation impairment (GOS 4.0 +/- 0.60 vs. 3.6 +/- 0.80; P = 0.08). CONCLUSIONS Hemispheric differences in cerebral autoregulation were common in children with isolated focal TBI. Absence of TBI on CT was not always associated with intact cerebral autoregulation. Patients with bilaterally intact cerebral autoregulation tended to have better outcomes.
Collapse
|
45
|
Dynamic cerebral autoregulation in carotid stenosis before and after carotid stenting. J Vasc Surg 2008; 48:88-92. [DOI: 10.1016/j.jvs.2008.02.025] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2007] [Revised: 01/29/2008] [Accepted: 02/01/2008] [Indexed: 11/20/2022]
|
46
|
Hu K, Peng C, Huang NE, Wu Z, Lipsitz LA, Cavallerano J, Novak V. Altered Phase Interactions between Spontaneous Blood Pressure and Flow Fluctuations in Type 2 Diabetes Mellitus: Nonlinear Assessment of Cerebral Autoregulation. PHYSICA A 2008; 387:2279-2292. [PMID: 18432311 PMCID: PMC2329796 DOI: 10.1016/j.physa.2007.11.052] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Cerebral autoregulation (CA) is an important mechanism that involves dilation and constriction in arterioles to maintain relatively s cerebral blood flow in response to changes of systemic blood pressure. Traditional assessments of CA focus on the changes of cerebral blood flow velocity in response to large blood pressure fluctuations induced by interventions. This approach is not feasible for patients with impaired autoregulation or cardiovascular regulation. Here we propose a newly developed technique-the multimodal pressure-flow (MMPF) analysis, which assesses CA by quantifying nonlinear phase interactions between spontaneous oscillations in blood pressure and flow velocity during resting conditions. We show that CA in healthy subjects can be characterized by specific phase shifts between spontaneous blood pressure and flow velocity oscillations, and the phase shifts are significantly reduced in diabetic subjects. Smaller phase shifts between oscillations in the two variables indicate more passive dependence of blood flow velocity on blood pressure, thus suggesting impaired cerebral autoregulation. Moreover, the reduction of the phase shifts in diabetes is observed not only in previously-recognized effective region of CA (<0.1Hz), but also over the higher frequency range from ~0.1 to 0.4Hz. These findings indicate that Type 2 diabetes alters cerebral blood flow regulation over a wide frequency range and that this alteration can be reliably assessed from spontaneous oscillations in blood pressure and blood flow velocity during resting conditions. We also show that the MMPF method has better performance than traditional approaches based on Fourier transform, and is more sui for the quantification of nonlinear phase interactions between nonstationary biological signals such as blood pressure and blood flow.
Collapse
Affiliation(s)
- Kun Hu
- Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| | - C.K. Peng
- Division of Interdisciplinary Medicine & Biotechnology and Margret and H.A. Rey Institute for Nonlinear Dynamics in Medicine, Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA
| | - Norden E. Huang
- Research Center for Data Analysis, National Central University, Chungli, Taiwan, ROC
| | - Zhaohua Wu
- Center for Ocean-Land-Atmosphere Studies, Calverton, Maryland
| | - Lewis A. Lipsitz
- Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
- Hebrew SeniorLife, Boston MA
| | | | - Vera Novak
- Division of Gerontology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA
| |
Collapse
|
47
|
Vernooij MW, van der Lugt A, Ikram MA, Wielopolski PA, Vrooman HA, Hofman A, Krestin GP, Breteler MMB. Total cerebral blood flow and total brain perfusion in the general population: the Rotterdam Scan Study. J Cereb Blood Flow Metab 2008; 28:412-9. [PMID: 17622253 DOI: 10.1038/sj.jcbfm.9600526] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Reduced cerebral perfusion may contribute to the development of cerebrovascular and neurodegenerative diseases. Little is known on cerebral perfusion in the general population, as most measurement techniques are too invasive for application in large groups of healthy individuals. Total cerebral blood flow (tCBF) can be noninvasively measured by magnetic resonance imaging (MRI) but is highly correlated with brain volume. We calculated total brain perfusion by dividing tCBF by brain volume, and we investigated determinants of total brain perfusion in comparison with tCBF. Secondly, we studied whether persons with a low tCBF or low total brain perfusion have a larger volume of white matter lesions (WML). This study is based on 892 persons aged 60 to 91 years from the Rotterdam Study, a population-based cohort study. We performed two-dimensional (2D) phase-contrast MRI for tCBF measurement. Brain volume and WML volume were quantitatively assessed. Cardiovascular determinants were assessed by interview and physical examination. We assessed associations between cardiovascular determinants and flow measures with linear regression models, adjusted for age and sex. Associations between tCBF or total brain perfusion and WML volume were assessed using general linear models. We found that determinants of tCBF and total brain perfusion differed largely due to the large influence of brain volume on tCBF values. Persons with low total brain perfusion had a significantly larger WML volume compared with those with high total brain perfusion. Prospective studies are required to unravel whether hypoperfusion contributes to WML formation or that tissue damage, manifested by WML, leads to brain hypoperfusion.
Collapse
Affiliation(s)
- Meike W Vernooij
- Department of Epidemiology & Biostatistics, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | | | | | | | | | | | | | | |
Collapse
|
48
|
Chapter 56 General principles of acute stroke management. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/s0072-9752(08)94056-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
|
49
|
Telman G, Kouperberg E, Sprecher E, Yarnitsky D. Acceleation of cerebrovascular reactivity as a new supplemental TCD index in patients with severe carotid stenosis before and after carotid endarterectomy. Neurol Res 2007; 29:p490-p492. [PMID: 17535573 DOI: 10.1179/016164107x164085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Affiliation(s)
- Gregory Telman
- Department of Neurology, Rambam Medical Center, Haifar, Israel
| | | | | | | |
Collapse
|
50
|
Treger I, Shafir O, Keren O, Ring H. Orthostatic hypotension and cerebral blood flow velocity in the rehabilitation of stroke patients. Int J Rehabil Res 2006; 29:339-42. [PMID: 17106353 DOI: 10.1097/mrr.0b013e328010c87d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The objective of this study was to investigate the results of transcranial Doppler monitoring during tilt table tests in stroke patients with and without orthostatic hypotension. In stroke patients without orthostatic hypotension, the mean flow velocity was almost similar in both middle cerebral arteries and was stable during the test. In patients with orthostatic hypotension symptoms, a significant difference was found between the two hemispheres. Mean flow velocity in the damaged middle cerebral artery was lower in the supine position and stayed almost the same at 80 degrees standing. In the non-damaged middle cerebral artery, however, the mean flow velocity was much higher when supine and dropped in the standing position. These findings suggest that the appearance of orthostatic hypotension symptoms may be associated in post-stroke patients with decreased blood velocity in the damaged middle cerebral artery. Those patients are at a high risk of developing syncopal reactions and should be treated on the tilt table with caution, especially at the beginning of the rehabilitation.
Collapse
Affiliation(s)
- Iuly Treger
- Loewenstein Rehabilitation Hospital, Ra'anana and Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | | | | | | |
Collapse
|