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Auger N, Paradis G, Healy-Profitós J, Lewin A, Malik M, Potter BJ. Non-cardiac birth defects and long-term risk of cardiovascular hospitalisation. Heart 2024; 110:892-898. [PMID: 38772572 DOI: 10.1136/heartjnl-2023-323632] [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: 10/26/2023] [Accepted: 05/04/2024] [Indexed: 05/23/2024] Open
Abstract
BACKGROUND Patients with heart defects are at risk of developing cardiovascular disease. Our objective was to determine if non-cardiac birth defects are associated with the risk of cardiovascular hospitalisation. METHODS We conducted a longitudinal cohort study of 1 451 409 parous women in Quebec, Canada. We compared patients with cardiac and non-cardiac birth defects of the urinary, central nervous and other systems against patients without defects between 1989 and 2022. The main outcome was hospitalisation for coronary artery disease, ischaemic stroke and other cardiovascular outcomes during 33 years of follow-up. We computed cardiovascular hospitalisation rates and used Cox proportional hazards regression models to measure the association (HR; 95% CI) between non-cardiac defects and later risk of cardiovascular hospitalisation, adjusted for patient characteristics. RESULTS Women with any birth defect had a higher rate of cardiovascular hospitalisation than women without defects (7.0 vs 3.3 per 1000 person-years). Non-cardiac defects overall were associated with 1.61 times the risk of cardiovascular hospitalisation over time, compared with no defect (95% CI 1.56 to 1.66). Isolated urinary (HR 3.93, 95% CI 3.65 to 4.23), central nervous system (HR 3.33, 95% CI 2.94 to 3.76) and digestive defects (HR 2.39, 95% CI 2.16 to 2.65) were associated with the greatest risk of cardiovascular hospitalisation. These anomalies were associated with cardiovascular hospitalisation whether they presented alone or clustered with other defects. Nevertheless, heart defects were associated with the greatest risk of cardiovascular hospitalisation (HR 10.30, 95% CI 9.86 to 10.75). CONCLUSION The findings suggest that both cardiac and non-cardiac birth defects are associated with an increased risk of developing cardiovascular disease among parous women.
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Affiliation(s)
- Nathalie Auger
- University of Montreal Hospital Centre Research Centre, Montreal, Québec, Canada
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Québec, Canada
- Institut national de santé publique du Québec, Montreal, Québec, Canada
- Department of Social and Preventive Medicine, University of Montreal, Montreal, Québec, Canada
| | - Gilles Paradis
- Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montreal, Québec, Canada
- Institut national de santé publique du Québec, Montreal, Québec, Canada
| | - Jessica Healy-Profitós
- University of Montreal Hospital Centre Research Centre, Montreal, Québec, Canada
- Institut national de santé publique du Québec, Montreal, Québec, Canada
| | - Antoine Lewin
- Department of Obstetrics and Gynecology, University of Sherbrooke, Sherbrooke, Québec, Canada
- Medical Affairs and Innovation, Hema-Quebec, Montreal, Québec, Canada
| | - Mariyam Malik
- University of Montreal Hospital Centre Research Centre, Montreal, Québec, Canada
- Institut national de santé publique du Québec, Montreal, Québec, Canada
| | - Brian J Potter
- Division of Cardiology, Department of Medicine, University of Montreal Hospital Centre, Montreal, Québec, Canada
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2
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West CR, Cragg JJ. Getting to the Heart of the Problem in Spinal Cord Injury. J Am Coll Cardiol 2024; 83:752-754. [PMID: 38355245 DOI: 10.1016/j.jacc.2023.12.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Accepted: 12/07/2023] [Indexed: 02/16/2024]
Affiliation(s)
- Christopher R West
- Centre for Chronic Disease Prevention and Management, University of British Columbia, Vancouver, British Columbia, Canada; Faculty of Medicine, Department of Cell and Physiological Sciences, University of British Columbia, Vancouver, British Columbia, Canada; International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada.
| | - Jacquelyn J Cragg
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada; Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
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3
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Calderón-Juárez M, Samejima S, Rempel L, Sachdeva R, Krassioukov A. Autonomic dysreflexia in urological practice: pathophysiology, prevention and treatment considerations. World J Urol 2024; 42:80. [PMID: 38358540 DOI: 10.1007/s00345-024-04781-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 01/09/2024] [Indexed: 02/16/2024] Open
Abstract
PURPOSE Spinal cord injury (SCI) leads to sensorimotor impairments; however, it can also be complicated by significant autonomic dysfunction, including cardiovascular and lower urinary tract (LUT) dysfunctions. Autonomic dysreflexia (AD) is a dangerous cardiovascular complication of SCI often overlooked by healthcare professionals. AD is characterized by a sudden increase in blood pressure (BP) that can result in severe cardiovascular and cerebrovascular complications. In this review, we provide an overview on the clinical manifestations, risk factors, underlying mechanisms, and current approaches in prevention and management of AD. METHODS After conducting a literature research, we summarized relevant information regarding the clinical and pathophysiological aspects in the context of urological clinical practice CONCLUSIONS: The most common triggers of AD are those arising from LUT, such as bladder distention and urinary tract infections. Furthermore, AD is commonly observed in individuals with SCI during urological procedures, including catheterization, cystoscopy and urodynamics. Although significant progress in the clinical assessment of AD has been made in recent decades, effective approaches for its prevention and treatment are currently lacking.
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Affiliation(s)
- Martín Calderón-Juárez
- International Collaboration On Repair Discoveries, Faculty of Medicine, The University of British Columbia, 818 West 10th Avenue, Vancouver, BC, V5Z 1M9, Canada
- Division of Physical Medicine and Rehabilitation, Department of Medicine, The University of British Columbia, Vancouver, Canada
| | - Soshi Samejima
- International Collaboration On Repair Discoveries, Faculty of Medicine, The University of British Columbia, 818 West 10th Avenue, Vancouver, BC, V5Z 1M9, Canada
- Division of Physical Medicine and Rehabilitation, Department of Medicine, The University of British Columbia, Vancouver, Canada
| | - Lucas Rempel
- International Collaboration On Repair Discoveries, Faculty of Medicine, The University of British Columbia, 818 West 10th Avenue, Vancouver, BC, V5Z 1M9, Canada
- Faculty of Medicine, The University of British Columbia, Vancouver, Canada
| | - Rahul Sachdeva
- International Collaboration On Repair Discoveries, Faculty of Medicine, The University of British Columbia, 818 West 10th Avenue, Vancouver, BC, V5Z 1M9, Canada
- Division of Physical Medicine and Rehabilitation, Department of Medicine, The University of British Columbia, Vancouver, Canada
| | - Andrei Krassioukov
- International Collaboration On Repair Discoveries, Faculty of Medicine, The University of British Columbia, 818 West 10th Avenue, Vancouver, BC, V5Z 1M9, Canada.
- Division of Physical Medicine and Rehabilitation, Department of Medicine, The University of British Columbia, Vancouver, Canada.
- GF Strong Rehabilitation Centre, Vancouver Coastal Health, Vancouver, BC, Canada.
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4
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Balasuberamaniam P, Wasim A, Shrikumar M, Chen T, Anthony T, Phillips A, Nathens A, Chapman M, Crawford E, Schwartz CE, Finkelstein J. Predictors of hospital-acquired pressure injuries in patients with complete spinal cord injury: a retrospective case-control study. BMC Musculoskelet Disord 2023; 24:329. [PMID: 37101130 PMCID: PMC10131324 DOI: 10.1186/s12891-023-06369-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 03/24/2023] [Indexed: 04/28/2023] Open
Abstract
BACKGROUND Despite current best practices, pressure injuries (PI) remain a devastating and prevalent hospital-acquired complication for patients with acute traumatic spinal cord injuries (SCIs). This study examined associations between risk factors for PI development in patients with complete SCI, such as norepinephrine dose and duration, and other demographic factors or lesion characteristics. METHODS This case-control study included adults with acute complete SCIs ASIA-A, who were admitted to a level-one trauma center between 2014-18. A retrospective review was implement using data on patient and injury characteristics, including age, gender, level of SCI (cervical vs. thoracic), Injury Severity Score (ISS), length of stay (LOS) and mortality; presence/absence of PI during their acute hospital stay; and treatment factors such as spinal surgery, mean arterial pressure (MAP) targets, and vasopressor treatment. Multivariable logistic regression evaluated associations with PI. RESULTS Eighty-two out of 103 eligible patients had complete data, and 30 (37%) developed PIs. Patient and injury characteristics, including age (Mean: 50.6; SD:21.3), location of SCI (48 cervical, 59%) and ISS (Mean 33.1; SD:11.8), did not differ between PI and non-PI groups. Logistic regression analysis revealed that male gender (OR:34.1; CI95:2.3-506.5, p = 0.010) and increased LOS (log-transformed; OR:20.5, CI95:2.8-149.9, p = 0.003) were associated with increased risk of PI. Having an order for a MAP > 80mmg (OR:0.05; CI95:0.01-0.30, p = 0.001) was associated with a reduced risk of PI. There were no significant associations between PI and duration of norepinephrine treatment. CONCLUSIONS Norepinephrine treatment parameters were not associated with development of PI, suggesting that MAP targets should be a focus for future investigations for SCI management. Increasing LOS should highlight the need for high-risk PI prevention and vigilance.
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Affiliation(s)
| | - Abeer Wasim
- Division of Orthopedic Surgery, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Mopina Shrikumar
- Division of Orthopedic Surgery, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Tan Chen
- Division of Orthopedic Surgery, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Tracey Anthony
- Tory Trauma Program, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Andrea Phillips
- Tory Trauma Program, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Avery Nathens
- Tory Trauma Program, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Martin Chapman
- Critical Care Medicine and Anesthesia, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Eric Crawford
- Division of Orthopedic Surgery, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
| | - Carolyn E Schwartz
- DeltaQuest Foundation, 31 Mitchell Road, Concord, MA, 01742, USA.
- Departments of Medicine and Orthopaedic Surgery, Tufts University School of Medicine, Boston, MA, USA.
| | - Joel Finkelstein
- Division of Orthopedic Surgery, Sunnybrook Health Sciences Centre, Toronto, ON, Canada
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5
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Sarafis ZK, Squair JW, Barak OF, Coombs GB, Soriano JE, Larkin-Kaiser KA, Lee AHX, Hansen A, Vodopic M, Romac R, Grant C, Charbonneau R, Mijacika T, Krassioukov AV, Ainslie PN, Dujic Z, Phillips AA. Common carotid artery responses to the cold-pressor test are impaired in individuals with cervical spinal cord injury. Am J Physiol Heart Circ Physiol 2022; 323:H1311-H1322. [PMID: 36367686 DOI: 10.1152/ajpheart.00261.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Cervical spinal cord injury (SCI) leads to autonomic cardiovascular dysfunction that underlies the three- to fourfold elevated risk of cardiovascular disease in this population. Reduced common carotid artery (CCA) dilatory responsiveness during the cold-pressor test (CPT) is associated with greater cardiovascular disease risk and progression. The cardiovascular and CCA responses to the CPT may provide insight into cardiovascular autonomic dysfunction and cardiovascular disease risk in individuals with cervical SCI. Here, we used CPT to perturb the autonomic nervous system in 14 individuals with cervical SCI and 12 uninjured controls, while measuring cardiovascular responses and CCA diameter. The CCA diameter responses were 55% impaired in those with SCI compared with uninjured controls (P = 0.019). The CCA flow, velocity, and shear response to CPT were reduced in SCI by 100% (P < 0.001), 113% (P = 0.001), and 125% (P = 0.002), respectively. The association between mean arterial pressure and CCA dilation observed in uninjured individuals (r = 0.54, P = 0.004) was absent in the SCI group (r = 0.22, P = 0.217). Steady-state systolic blood pressure (P = 0.020), heart rate (P = 0.003), and cardiac contractility (P < 0.001) were reduced in those with cervical SCI, whereas total peripheral resistance was increased compared with uninjured controls (P = 0.042). Relative cerebral blood velocity responses to CPT were increased in the SCI group and reduced in controls (middle cerebral artery, P = 0.010; posterior cerebral artery, P = 0.026). The CCA and cardiovascular responsiveness to CPT are impaired in those with cervical SCI.NEW & NOTEWORTHY This is the first study demonstrating that CCA responses during CPT are suppressed in SCI. Specifically, CCA diameter, flow, velocity, and shear rate were reduced. The relationship between changes in MAP and CCA dilatation in response to CPT was absent in individuals with SCI, despite similar cardiovascular activation between SCI and uninjured controls. These findings support the notion of elevated cardiovascular disease risk in SCI and that the cardiovascular responses to environmental stimuli are impaired.
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Affiliation(s)
- Zoe K Sarafis
- International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jordan W Squair
- International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,RESTORE.network, Departments of Physiology and Pharmacology, Cardiac Sciences and Clinical Neurosciences, Biomedical Engineering, Libin Cardiovascular Institute of Alberta, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,MD/PhD Training Program, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Experimental Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Otto F Barak
- Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia
| | - Geoff B Coombs
- Centre for Heart, Lung and Vascular Health, University of British Columbia Okanagan, Kelowna, British Columbia, Canada
| | - Jan Elaine Soriano
- RESTORE.network, Departments of Physiology and Pharmacology, Cardiac Sciences and Clinical Neurosciences, Biomedical Engineering, Libin Cardiovascular Institute of Alberta, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Kelly A Larkin-Kaiser
- RESTORE.network, Departments of Physiology and Pharmacology, Cardiac Sciences and Clinical Neurosciences, Biomedical Engineering, Libin Cardiovascular Institute of Alberta, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Amanda H X Lee
- International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Experimental Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Alex Hansen
- Department of Sport Science, University of Innsbruck, Innsbruck, Austria
| | - Maro Vodopic
- Department of Neurology, General Hospital, Dubrovnik, Croatia
| | - Rinaldo Romac
- Department of Neurology, Clinical Hospital Center, Split, Croatia
| | - Christopher Grant
- Division of Physical Medicine and Rehabilitation, Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Rebecca Charbonneau
- Division of Physical Medicine and Rehabilitation, Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Tanja Mijacika
- Department of Integrative Physiology, University of Split School of Medicine, Split, Croatia
| | - Andrei V Krassioukov
- International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,Division of Physical Medicine and Rehabilitation, University of British Columbia, Vancouver, British Columbia, Canada.,GF Strong Rehabilitation Centre, Vancouver, British Columbia, Canada
| | - Philip N Ainslie
- Centre for Heart, Lung and Vascular Health, University of British Columbia Okanagan, Kelowna, British Columbia, Canada
| | - Zeljko Dujic
- Department of Integrative Physiology, University of Split School of Medicine, Split, Croatia
| | - Aaron A Phillips
- RESTORE.network, Departments of Physiology and Pharmacology, Cardiac Sciences and Clinical Neurosciences, Biomedical Engineering, Libin Cardiovascular Institute of Alberta, Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
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6
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Balthazaar SJ, Sengeløv M, Bartholdy K, Malmqvist L, Ballegaard M, Hansen B, Svendsen JH, Kruse A, Welling KL, Krassioukov AV, Biering-Sørensen F, Biering-Sørensen T. Cardiac arrhythmias six months following traumatic spinal cord injury. J Spinal Cord Med 2022; 45:631-637. [PMID: 34292114 PMCID: PMC9246248 DOI: 10.1080/10790268.2021.1950453] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
OBJECTIVE To investigate the incidence of cardiac arrhythmias at six months following traumatic spinal cord injury (SCI) and to compare the prevalence of arrhythmias between participants with cervical and thoracic SCI. DESIGN A prospective observational study using continuous twenty-four-hour Holter monitoring. SETTING Inpatient rehabilitation unit of a university research hospital and patient home setting. PARTICIPANTS Fifty-five participants with acute traumatic SCI were prospectively included. For each participant, the SCI was characterized according to the International Standards for Neurological Classification of SCI by the neurological level and severity according to the American Spinal Injury Association Impairment Scale. OUTCOME MEASURES Comparisons between demographic characteristics and arrhythmogenic occurrences as early as possible after SCI (4 ± 2 days) followed by 1, 2, 3, 4 weeks and 6 month time points of Holter monitoring. RESULTS Bradycardia (heart rate [HR] <50 bpm) was present in 29% and 33% of the participants with cervical (C1-C8) and thoracic (T1-T12) SCI six months after SCI, respectively. The differences in episodes of bradycardia between the two groups were not significant (P < 0.54). The mean maximum HR increased significantly from 4 weeks to 6 months post-SCI (P < 0.001), however mean minimum and maximum HR were not significantly different between the groups at the six-month time point. There were no differences in many arrhythmias between recording periods or between groups at six months. CONCLUSIONS At the six-month timepoint following traumatic SCI, there were no significant differences in occurrences of arrhythmias between participants with cervical and thoracic SCI compared to the findings observed in the first month following SCI.
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Affiliation(s)
- Shane J.T. Balthazaar
- Department of Cardiology, Vancouver General Hospital, Vancouver Coastal Health, Vancouver, British Columbia (BC), Canada
| | - Morten Sengeløv
- Clinic for Spinal Cord Injuries, Rigshospitalet, Copenhagen, Denmark,Department of Cardiology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark,Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Kim Bartholdy
- Clinic for Spinal Cord Injuries, Rigshospitalet, Copenhagen, Denmark
| | - Lasse Malmqvist
- Clinic for Spinal Cord Injuries, Rigshospitalet, Copenhagen, Denmark,Department of Clinical Neurophysiology, Rigshopitalet, Copenhagen, Denmark
| | - Martin Ballegaard
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark,Department of Clinical Neurophysiology, Rigshopitalet, Copenhagen, Denmark,Department of Neurology, Zealand University Hospital at Roskilde, Roskilde, Denmark
| | - Birgitte Hansen
- Clinic for Spinal Cord Injuries, Rigshospitalet, Copenhagen, Denmark
| | - Jesper Hastrup Svendsen
- Clinic for Spinal Cord Injuries, Rigshospitalet, Copenhagen, Denmark,Department of Cardiology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Anders Kruse
- Spine Unit, Department of Orthopedic Surgery, Rigshospitalet, Copenhagen, Denmark
| | | | - Andrei V. Krassioukov
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia (UBC), Vancouver, BC, Canada,Department of Medicine, Division of Physical Medicine and Rehabilitation, Vancouver, BC, Canada,Spinal Cord Program, GF Strong Rehabilitation Centre, University of British Columbia, Vancouver, BC, Canada
| | - Fin Biering-Sørensen
- Clinic for Spinal Cord Injuries, Rigshospitalet, Copenhagen, Denmark,Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Tor Biering-Sørensen
- Clinic for Spinal Cord Injuries, Rigshospitalet, Copenhagen, Denmark,Department of Cardiology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark,Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark,Correspondence to: Tor Biering-Sørensen, Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen; Cardiovascular Non-Invasive Imaging Research Laboratory Department of Cardiology, Herlev & Gentofte Hospital, Niels Andersensvej 65, DK-2900, Post 835, Copenhagen, Denmark.
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7
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Balthazaar SJT, Nightingale TE, Currie KD, West CR, Tsang TSM, Walter M, Krassioukov AV. Temporal Changes of Cardiac Structure, Function, and Mechanics During Sub-acute Cervical and Thoracolumbar Spinal Cord Injury in Humans: A Case-Series. Front Cardiovasc Med 2022; 9:881741. [PMID: 35783818 PMCID: PMC9240304 DOI: 10.3389/fcvm.2022.881741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 05/24/2022] [Indexed: 11/13/2022] Open
Abstract
Individuals with cervical spinal cord injury (SCI) experience deleterious changes in cardiac structure and function. However, knowledge on when cardiac alterations occur and whether this is dependent upon neurological level of injury remains to be determined. Transthoracic echocardiography was used to assess left ventricular structure, function, and mechanics in 10 male individuals (median age 34 years, lower and upper quartiles 32–50) with cervical (n = 5, c-SCI) or thoracolumbar (n = 5, tl-SCI) motor-complete SCI at 3- and 6-months post-injury. Compared to the 3-month assessment, individuals with c-SCI displayed structural, functional, and mechanical changes during the 6-month assessment, including significant reductions in end diastolic volume [121 mL (104–139) vs. 101 mL (99–133), P = 0.043], stroke volume [75 mL (61–85) vs. 60 mL (58–80), P = 0.042], myocardial contractile velocity (S') [0.11 m/s (0.10–0.13) vs. 0.09 m/s (0.08–0.10), P = 0.043], and peak diastolic longitudinal strain rate [1.29°/s (1.23–1.34) vs. 1.07°/s (0.95–1.15), P = 0.043], and increased early diastolic filling over early myocardial relaxation velocity (E/E') ratio [5.64 (4.71–7.72) vs. 7.48 (6.42–8.42), P = 0.043]. These indices did not significantly change in individuals with tl-SCI between time points. Ejection fraction was different between individuals with c-SCI and tl-SCI at 3 [61% (57–63) vs. 54% (52–55), P < 0.01] and 6 months [58% (57–62) vs. 55% (52–56), P < 0.01], though values were considered normal. These results demonstrate that individuals with c-SCI exhibit significant reductions in cardiac function from 3 to 6 months post-injury, whereas individuals with tl-SCI do not, suggesting the need for early rehabilitation to minimize cardiac consequences in this specific population.
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Affiliation(s)
- Shane J. T. Balthazaar
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC, Canada
- Experimental Medicine Program, Faculty of Medicine, University of British Columbia (UBC), Vancouver, BC, Canada
| | - Tom E. Nightingale
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC, Canada
- School of Sport, Exercise, and Rehabilitation Sciences, University of Birmingham, Birmingham, United Kingdom
- Centre for Trauma Science Research, University of Birmingham, Birmingham, United Kingdom
| | - Katharine D. Currie
- Department of Kinesiology, Michigan State University, East Lansing, MI, United States
| | - Christopher R. West
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC, Canada
- Department of Cellular and Physiological Sciences, Faculty of Medicine, UBC, Vancouver, BC, Canada
| | - Teresa S. M. Tsang
- Department of Cardiology, Vancouver General and UBC Hospitals, Vancouver Coastal Health, Vancouver, BC, Canada
| | - Matthias Walter
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC, Canada
- Department of Urology, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Andrei V. Krassioukov
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, BC, Canada
- Division of Physical Medicine and Rehabilitation, Faculty of Medicine, UBC, Vancouver, BC, Canada
- GF Strong Rehabilitation Centre, Vancouver Coastal Health, Vancouver, BC, Canada
- *Correspondence: Andrei V. Krassioukov
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8
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Balik V, Šulla I. Autonomic Dysreflexia following Spinal Cord Injury. Asian J Neurosurg 2022; 17:165-172. [PMID: 36120615 PMCID: PMC9473833 DOI: 10.1055/s-0042-1751080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
AbstractAutonomic dysreflexia (AD) is a potentially life-threatening condition of the autonomic nervous system following spinal cord injury at or above T6. One of the most common symptoms is a sudden increase in blood pressure induced by afferent sensory stimulation owing to unmodulated reflex sympathetic hyperactivity. Such episodes of high blood pressure might be associated with a high risk of cerebral or retinal hemorrhage, seizures, heart failure, or pulmonary edema. In-depth knowledge is, therefore, crucial for the proper management of the AD, especially for spine surgeons, who encounter these patients quite often in their clinical practice. Systematical review of the literature dealing with strategies to prevent and manage this challenging condition was done by two independent reviewers. Studies that failed to assess primary (prevention, treatment strategies and management) and secondary outcomes (clinical symptomatology, presentation) were excluded. A bibliographical search revealed 85 eligible studies that provide a variety of preventive and treatment measures for the subjects affected by AD. As these measures are predominantly based on noncontrolled trials, long-term prospectively controlled multicenter studies are warranted to validate these preventive and therapeutic proposals.
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Affiliation(s)
- Vladimír Balik
- Department of Neurosurgery, Svet Zdravia Hospital, Michalovce, Slovakia
| | - Igor Šulla
- Department of Anatomy, University of Veterinary Medicine and Pharmacy, Histology and Physiology, Košice, Slovakia
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9
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Evaluation of the Cardiometabolic Disorders after Spinal Cord Injury in Mice. BIOLOGY 2022; 11:biology11040495. [PMID: 35453695 PMCID: PMC9027794 DOI: 10.3390/biology11040495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 03/17/2022] [Accepted: 03/20/2022] [Indexed: 11/16/2022]
Abstract
Changes in cardiometabolic functions contribute to increased morbidity and mortality after chronic spinal cord injury. Despite many advancements in discovering SCI-induced pathologies, the cardiometabolic risks and divergences in severity-related responses have yet to be elucidated. Here, we examined the effects of SCI severity on functional recovery and cardiometabolic functions following moderate (50 kdyn) and severe (75 kdyn) contusions in the thoracic-8 (T8) vertebrae in mice using imaging, morphometric, and molecular analyses. Both severities reduced hindlimbs motor functions, body weight (g), and total body fat (%) at all-time points up to 20 weeks post-injury (PI), while only severe SCI reduced the total body lean (%). Severe SCI increased liver echogenicity starting from 12 weeks PI, with an increase in liver fibrosis in both moderate and severe SCI. Severe SCI mice showed a significant reduction in left ventricular internal diameters and LV volume at 20 weeks PI, associated with increased LV ejection fraction as well as cardiac fibrosis. These cardiometabolic dysfunctions were accompanied by changes in the inflammation profile, varying with the severity of the injury, but not in the lipid profile nor cardiac or hepatic tyrosine hydroxylase innervation changes, suggesting that systemic inflammation may be involved in these SCI-induced health complications.
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10
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A Hierarchical Machine Learning Solution for the Non-Invasive Diagnostic of Autonomic Dysreflexia. ELECTRONICS 2022. [DOI: 10.3390/electronics11040584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
More than half of patients with high spinal cord injury (SCI) suffer from episodes of autonomic dysreflexia (AD), a condition that can lead to lethal situations, such as cerebral haemorrhage, if not treated correctly. Clinicians assess AD using clinical variables obtained from the patient’s history and physiological variables obtained invasively and non-invasively. This work aims to design a machine learning-based system to assist in the initial diagnosis of AD. For this purpose, 29 patients with SCI participated in a test at Cruces University Hospital in which data were collected using both invasive and non-invasive methods. The system proposed in this article is based on a two-level hierarchical classification to diagnose AD and only uses 35 features extracted from the non-invasive stages of the experiment (clinical and physiological features). The system achieved a 93.10% accuracy with a zero false negative rate for the class of having the disease, an essential condition for treating patients according to medical criteria.
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11
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Fauss GNK, Strain MM, Huang YJ, Reynolds JA, Davis JA, Henwood MK, West CR, Grau JW. Contribution of Brain Processes to Tissue Loss After Spinal Cord Injury: Does a Pain-Induced Rise in Blood Pressure Fuel Hemorrhage? Front Syst Neurosci 2022; 15:733056. [PMID: 34975424 PMCID: PMC8714654 DOI: 10.3389/fnsys.2021.733056] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 11/09/2021] [Indexed: 11/13/2022] Open
Abstract
Pain (nociceptive) input soon after spinal cord injury (SCI) expands the area of tissue loss (secondary injury) and impairs long-term recovery. Evidence suggests that nociceptive stimulation has this effect because it promotes acute hemorrhage. Disrupting communication with the brain blocks this effect. The current study examined whether rostral systems exacerbate tissue loss because pain input drives an increase in systolic blood pressure (BP) and flow that fuels blood infiltration. Rats received a moderate contusion injury to the lower thoracic (T12) spinal cord. Communication with rostral processes was disrupted by cutting the spinal cord 18 h later at T2. Noxious electrical stimulation (shock) applied to the tail (Experiment 1), or application of the irritant capsaicin to one hind paw (Experiment 2), increased hemorrhage at the site of injury. Shock, but not capsaicin, increased systolic BP and tail blood flow in sham-operated rats. Cutting communication with the brain blocked the shock-induced increase in systolic BP and tail blood flow. Experiment 3 examined the effect of artificially driving a rise in BP with norepinephrine (NE) in animals that received shock. Spinal transection attenuated hemorrhage in vehicle-treated rats. Treatment with NE drove a robust increase in BP and tail blood flow but did not increase the extent of hemorrhage. The results suggest pain input after SCI can engage rostral processes that fuel hemorrhage and drive sustained cardiovascular output. An increase in BP was not, however, necessary or sufficient to drive hemorrhage, implicating other brain-dependent processes.
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Affiliation(s)
- Gizelle N K Fauss
- Department of Psychological and Brain Sciences, Texas A&M University, College Station, TX, United States
| | - Misty M Strain
- Department of Cellular and Integrative Physiology, University of Texas Health Science San Antonio, San Antonio, TX, United States
| | | | - Joshua A Reynolds
- Department of Psychological and Brain Sciences, Texas A&M University, College Station, TX, United States
| | - Jacob A Davis
- Department of Psychological and Brain Sciences, Texas A&M University, College Station, TX, United States
| | - Melissa K Henwood
- Department of Psychological and Brain Sciences, Texas A&M University, College Station, TX, United States
| | - Christopher R West
- Centre for Chronic Disease Prevention and Management, Faculty of Medicine, University of British Columbia, Kelowna, BC, Canada
| | - James W Grau
- Department of Psychological and Brain Sciences, Texas A&M University, College Station, TX, United States
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12
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Burns M, Solinsky R. Toward rebalancing blood pressure instability after spinal cord injury with spinal cord electrical stimulation: A mini review and critique of the evolving literature. Auton Neurosci 2022; 237:102905. [PMID: 34800845 PMCID: PMC9280330 DOI: 10.1016/j.autneu.2021.102905] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 10/07/2021] [Accepted: 11/06/2021] [Indexed: 01/03/2023]
Abstract
High-level spinal cord injury commonly leads to blood pressure instability. This manifests clinically as orthostatic hypotension (OH), where blood pressure can drop to the point of loss of consciousness, and autonomic dysreflexia (AD), where systolic blood pressure can climb to over 300 mmHg in response to an unperceived noxious stimulus. These blood pressure fluctuations can occur multiple times a day, contributing to increased vessel shear stress and heightened risk of cardiovascular disease. The pathophysiology of both of these conditions is rooted in impairments in regulation of spinal cord sympathetic preganglionic neurons, which control blood pressure by mediating vascular resistance and catecholamine release. Recently, spinal cord electrical stimulation has provided evidence that it may modulate these blood pressure imbalances. Early proposed mechanisms suggest activation of spinal cord dorsal horn neurons that ultimately act upon the sympathetic preganglionic neuronal pathways. For OH, spinal cord stimulation likely induces local activation of these neurons to generate baseline sympathetic tone and accompanying vasoconstriction. The mechanisms for spinal stimulation regulating AD are less clear, though some suggest it activates inhibitory circuits to dampen the overactive sympathetic response. While questions remain, spinal cord electrical stimulation is an intriguing new modality that may restore blood pressure regulation following spinal cord injury.
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Affiliation(s)
- Madeleine Burns
- Boston University School of Medicine, Graduate Medical Sciences
| | - Ryan Solinsky
- Spaulding Rehabilitation Hospital,Department of Physical Medicine & Rehabilitation, Harvard Medical School,Spaulding Research Institute
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13
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Kaydok E. Nurses and physiotherapists' knowledge levels on autonomic dysreflexia in a rehabilitation hospital. J Spinal Cord Med 2021:1-5. [PMID: 34855570 DOI: 10.1080/10790268.2021.1983313] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
OBJECTIVE Autonomic dysreflexia is a clinical syndrome that affects people with spinal cord lesions at or above the sixth thoracic vertebral level (T6). This study aims to determine the level of knowledge about autonomic dysreflexia among nurses and physiotherapists involved in spinal cord rehabilitation. DESIGN Single-center survey study. SETTING This was conducted at a rehabilitation hospital. OUTCOME MEASURE : Autonomic dysreflexia knowledge test. PARTICIPANTS Nurses (N = 36) and physiotherapists (N = 32) working at a local rehabilitation hospital participated in this study. RESULTS In the autonomic dysreflexia knowledge test, the nurses obtained an average score of 6.63 ± 2.2 and the physiotherapists obtained an average score of 6.87 ± 1.89; there was no significant difference between the two groups (P > 0.05). Less than 25% of the participants had experience with autonomic dysreflexia and the test scores of the participants with this experience were significantly higher (P < 0.001). CONCLUSION Similar to previous studies, the knowledge level of autonomic dysreflexia among nurses and physiotherapists working in rehabilitation hospitals was low. We think that there is a need for internationally standardized training programs to increase the knowledge level of autonomic dysreflexia for patients, caregivers, and health professionals.
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Affiliation(s)
- Ercan Kaydok
- Department of Physical Medicine and Rehabilitation, Niğde Ömer Halisdemir University Faculty of Medicine, Niğde, Turkey
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14
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Higher Physical Activity Level Improves Leptin Concentrations in Spinal Cord Injury Subjects. BIOMED RESEARCH INTERNATIONAL 2021; 2021:9415253. [PMID: 34621899 PMCID: PMC8492252 DOI: 10.1155/2021/9415253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 08/10/2021] [Accepted: 09/09/2021] [Indexed: 11/26/2022]
Abstract
The present study was designed to compare the body composition and indicators of chronic inflammatory grade, such as leptin, adiponectin, and resistin concentrations in irregularly active and active SCI subjects. Thirty-two male subjects participated in this study. They were divided into three groups: able-bodied control irregularly active (control, n = 11), irregularly active with SCI (SCI-IA, n = 8), and physically active with SCI (SCI-PA, n = 13). The enzyme-linked immunosorbent assay (ELISA) assessed serum concentrations of leptin, adiponectin, and resistin. All volunteers performed the maximum oxygen uptake (VO2max) test, 24 h total energy expenditure (TEE), and body composition by skinfold thicknesses. Leptin concentrations were higher in the SCI-IA group when compared to the other groups, while no significant differences were found between the SCI-PA and control cohorts. In addition, no significant differences were found among groups for serum adiponectin and resistin concentrations either. The SCI-PA group showed significantly higher values for TEE and VO2max when compared to the other groups. Percentages of body fat and circumference were decreased in the control and SCI-PA groups when compared to the SCI-IA cohort. Associations between leptin and cardiorespiratory capacity and anthropometric markers were also observed. Our findings highlight that the lack of physical activity in the SCI subjects leads to poor general physical fitness and higher levels of body adiposity, which may induce hyperleptinemia, an essential marker for cardiometabolic disorders.
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15
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Hayes BD, Fossey MPM, Poormasjedi-Meibod MS, Erskine E, Soriano JE, Scott B, Rosentreter R, Granville DJ, Phillips AA, West CR. Experimental high thoracic spinal cord injury impairs the cardiac and cerebrovascular response to orthostatic challenge in rats. Am J Physiol Heart Circ Physiol 2021; 321:H716-H727. [PMID: 34448635 DOI: 10.1152/ajpheart.00239.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 08/24/2021] [Indexed: 11/22/2022]
Abstract
Spinal cord injury (SCI) impairs the cardiovascular responses to postural challenge, leading to the development of orthostatic hypotension (OH). Here, we apply lower body negative pressure (LBNP) to rodents with high-level SCI to demonstrate the usefulness of LBNP as a model for experimental OH studies, and to explore the effect of simulated OH on cardiovascular and cerebrovascular function following SCI. Male Wistar rats (n = 34) were subjected to a sham or T3-SCI surgery and survived into the chronic period postinjury (i.e., 8 wk). Cardiac function was tracked via ultrasound pre- to post-SCI to demonstrate the clinical utility of our model. At study termination, we conducted left-ventricular (LV) catheterization and insonated the middle cerebral artery to investigate the hemodynamic, cardiac, and cerebrovascular response to a mild dose of LBNP that is sufficient to mimic clinically defined OH in rats with T3-SCI but not sham animals. In response to mimicked OH, there was a greater decline in stroke volume, cardiac output, maximal LV pressure, and blood pressure in SCI compared with sham (P < 0.034), whereas heart rate was increased in sham but decreased in SCI (P < 0.029). SCI animals also had an exaggerated reduction in peak, minimum and mean middle cerebral artery flow, for a given change in blood pressure, in response to LBNP (P < 0.033), implying impaired dynamic cerebral autoregulation. Using a preclinical SCI model of OH, we demonstrate that complete high thoracic SCI impairs the cardiac response to OH and disrupts dynamic cerebral autoregulation.NEW & NOTEWORTHY This is the first use of LBNP to interrogate the cardiac and cerebrovascular responses to simulated OH in a preclinical study of SCI. Here, we demonstrate the utility of our simulated OH model and use it to demonstrate that SCI impairs the cardiac response to simulated OH and disrupts dynamic cerebrovascular autoregulation.
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Affiliation(s)
- Brian D Hayes
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Mary Pauline Mona Fossey
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- Experimental Medicine, Department of Medicine, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Erin Erskine
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Cellular and Physiological Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jan Elaine Soriano
- Departments of Physiology and Pharmacology, Cardiac Sciences, Clinical Neurosciences, Libin Cardiovascular Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Berkeley Scott
- Departments of Physiology and Pharmacology, Cardiac Sciences, Clinical Neurosciences, Libin Cardiovascular Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Ryan Rosentreter
- Departments of Physiology and Pharmacology, Cardiac Sciences, Clinical Neurosciences, Libin Cardiovascular Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - David J Granville
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Aaron A Phillips
- Departments of Physiology and Pharmacology, Cardiac Sciences, Clinical Neurosciences, Libin Cardiovascular Institute, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Christopher R West
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Cellular and Physiological Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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16
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Quantitative analysis of dysautonomia in patients with autonomic dysreflexia. J Neurol 2021; 268:2985-2994. [PMID: 33634338 DOI: 10.1007/s00415-021-10478-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2021] [Revised: 02/15/2021] [Accepted: 02/16/2021] [Indexed: 10/22/2022]
Abstract
Autonomic dysreflexia (AD) is a life-threatening condition for individuals with cervical or high-thoracic spinal cord injury (SCI). The profile of autonomic dysfunction in AD using validated clinical autonomic tests has not been described so far, although it could be useful to identify SCI patients at greater risk of developing AD non-invasively. With this objective, 37 SCI patients (27% female) were recruited, and hemodynamic and cardiac parameters were continuously monitored to determine the presence of AD, defined as an increase of systolic blood pressure of 20 mmHg or higher after bladder filling with saline. Then, standard autonomic function testing was performed, including Deep Breathing, Valsalva Manoeuvre and Tilt Table Test. Finally, baroreflex sensitivity (BRS), and spectral analysis of heart rate and blood pressure variability were measured at rest. Catecholamines and vasopressin levels were also measured at supine and upright positions. The severity of SCI was assessed through clinical and radiological examinations. AD was observed in 73.3% of SCI patients, being 63.6% of them asymptomatic during the dysreflexive episode. AD patients displayed a drop in sympathetic outflow, as determined by decreased noradrenalin plasma levels, reduced sympathovagal balance and increased BRS. In line with decreased sympathetic activity, the incidence of neurogenic orthostatic hypotension was higher in AD patients. Our results provide novel evidence regarding the autonomic dysfunction in SCI patients with AD compared to non-AD patients, posing non-invasively measured autonomic parameters as a powerful clinical tool to predict AD in SCI patients.
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17
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Minic Z, O’Leary DS, Reynolds CA. Purinergic receptor antagonism: A viable strategy for the management of autonomic dysreflexia? Auton Neurosci 2021; 230:102741. [PMID: 33220530 PMCID: PMC8855366 DOI: 10.1016/j.autneu.2020.102741] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/27/2020] [Accepted: 10/28/2020] [Indexed: 11/17/2022]
Abstract
The purinergic receptor ligand, ATP, may participate in reflex induced vasoconstriction through sympathetic efferent and sensory afferent mechanisms. However, the role of the purinergic system in contributing to autonomic dysreflexia following spinal cord injury is unclear. The present study investigates the involvement of P2X receptors in contributing to pressor responses during autonomic dysreflexia. Twenty rats were subjected to spinal cord injury and 24 h later hemodynamic responses to colorectal distension were recorded. Animals were randomized to receive intravenous administration of the P2X receptor antagonist, NF023, or vehicle control. The data indicate that NF023 attenuates pressor responses to colorectal distension.
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Affiliation(s)
- Zeljka Minic
- Department of Emergency Medicine, Wayne State University School of Medicine, Detroit, MI, USA; Department of Physiology, Immunology and Pathophysiology, University of Rijeka Medical School, Rijeka, Croatia.
| | - Donal S. O’Leary
- Department of Physiology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | - Christian A. Reynolds
- Department of Emergency Medicine, Wayne State University School of Medicine, Detroit, Michigan, USA,Department of Biotechnology, University of Rijeka, Rijeka, Croatia
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18
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Evaluation of cardiovascular disease risk in individuals with chronic spinal cord injury. Spinal Cord 2020; 59:716-729. [PMID: 33070157 DOI: 10.1038/s41393-020-00566-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 09/24/2020] [Accepted: 09/29/2020] [Indexed: 01/26/2023]
Abstract
STUDY DESIGN Multicentre, cross-sectional study. OBJECTIVES To identify which markers of obesity, injury characteristics and autonomic function variables are related to cardiovascular disease (CVD) risk after spinal cord injury (SCI), and establish cut-points for detection and risk management. SETTING Eight SCI rehabilitation centres in the Netherlands. METHODS Individuals (n = 257) with a traumatic, chronic (≥10 years) SCI, with age at injury between 18 and 35 years, completed a self-report questionnaire and a one-day visit to a rehabilitation centre for testing. Three anthropometric measures were tested: body mass index (BMI); waist circumference (WC); and waist-to-height ratio (WHtR). Injury characteristics included: American Spinal Injury Association impairment scale (AIS); duration of injury (DOI); and neurological level of injury (LOI). Cardiovascular autonomic function was assessed from peak heart rate during maximal exercise (HRpeak). Systolic arterial pressure (SAP) and aerobic capacity (VO2peak) were also determined. CVD risk was calculated using the Framingham risk score (FRS). RESULTS All anthropometric variables were associated with FRS, with WC showing the strongest correlation (r = 0.41, p < 0.001) and greatest area under the curve (0.73) for 10-year CVD risk (%). WC, DOI, SAP, HRpeak, LOI, and VO2peak (variable importance: 0.81, 1.0, 0.98, 0.98, 0.66, 0.68, respectively) were important predictive variables for 10-year CVD risk in individuals with SCI. CONCLUSIONS We confirm that WC is a simple, practical measure of CVD risk, and along with DOI and markers of cardiovascular autonomic function, plays a role in the increased CVD risk following SCI.
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19
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Walter M, Ruiz I, Squair JW, Rios LAS, Averbeck MA, Krassioukov AV. Prevalence of self-reported complications associated with intermittent catheterization in wheelchair athletes with spinal cord injury. Spinal Cord 2020; 59:1018-1025. [PMID: 33051562 PMCID: PMC8397616 DOI: 10.1038/s41393-020-00565-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 09/22/2020] [Accepted: 10/01/2020] [Indexed: 11/09/2022]
Abstract
STUDY DESIGN Cross-sectional study. OBJECTIVES To identify the prevalence of complications associated with intermittent catheterization in wheelchair athletes with spinal cord injury (SCI). SETTING International and national sporting events. METHODS A total 130 competitive wheelchair athletes living with SCI completed a self-reported questionnaire during international or national sporting events. The questionnaire collected information regarding demographics, injury characteristics, method of bladder emptying, and complications related to intermittent catheterization. RESULTS Overall, 84% (109/130) of wheelchair athletes used intermittent catheterization. Within this group, 77% of athletes (84/109) experienced at least one complication associated with intermittent catheterization. Twenty-seven percent (29/109) sustained urethral injuries and 63% (69/109) had at least one episode of urinary tract infection during the last 12 months. Almost one-fourth of male athletes (22/95, 23%) had a history of inflammation / infection of genital organs associated with intermittent catheterization. CONCLUSIONS Here we report a high prevalence of self-reported complications associated with intermittent catheterization in wheelchair athletes with SCI. Considering their potential impact on lower urinary tract function, athletic performance, and health, further studies are needed to assess the role of preventative strategies to reduce complications related to intermittent catheterization in wheelchair athletes with SCI. SPONSORSHIP Coloplast Brazil and Instituto Lado a Lado pela Vida (a nongovernmental, nonprofit organization based in São Paulo) and Wellspect provided funding for this study.
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Affiliation(s)
- Matthias Walter
- International Collaboration on Repair Discoveries (ICORD), Faculty of Medicine, University of British Columbia (UBC), Vancouver, British Columbia (BC), Canada.,Department of Urology, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Ian Ruiz
- International Collaboration on Repair Discoveries (ICORD), Faculty of Medicine, University of British Columbia (UBC), Vancouver, British Columbia (BC), Canada
| | - Jordan W Squair
- International Collaboration on Repair Discoveries (ICORD), Faculty of Medicine, University of British Columbia (UBC), Vancouver, British Columbia (BC), Canada
| | - Luis A S Rios
- Department of Urology, IAMSPE Hospital, São Paulo, Brazil.,Videourodynamic Unit, Albert Einstein Hospital, São Paulo, Brazil
| | - Marcio A Averbeck
- Department of Urology, Moinhos de Vento Hospital, Porto Alegre, Brazil
| | - Andrei V Krassioukov
- International Collaboration on Repair Discoveries (ICORD), Faculty of Medicine, University of British Columbia (UBC), Vancouver, British Columbia (BC), Canada. .,Division of Physical Medicine and Rehabilitation, Faculty of Medicine, UBC, Vancouver, BC, Canada. .,G.F. Strong Rehabilitation Centre, Vancouver, BC, Canada.
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20
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Systolic and diastolic function in chronic spinal cord injury. PLoS One 2020; 15:e0236490. [PMID: 32716921 PMCID: PMC7384657 DOI: 10.1371/journal.pone.0236490] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 07/07/2020] [Indexed: 12/24/2022] Open
Abstract
Individuals with spinal cord injury develop cardiovascular disease more than age-matched, non-injured cohorts. However, progression of systolic and diastolic dysfunction into cardiovascular disease after spinal cord injury is not well described. We sought to investigate the relationship between systolic and diastolic function in chronic spinal cord injury to describe how biological sex, level, severity, and duration of injury correlate with structural changes in the left ventricle. Individuals with chronic spinal cord injury participated in this study (n = 70). Registered diagnostic cardiac sonographers used cardiac ultrasound to measure dimensions, mass, and systolic and diastolic function of the left ventricle. We found no significant relationship to severity or duration of injury with left ventricle measurements, systolic function outcome, or diastolic function outcome. Moreover, nearly all outcomes measured were within the American Society of Echocardiography-defined healthy range. Similar to non-injured individuals, when indexed by body surface area (BSA) left ventricle mass [-14 (5) g/m2, p < .01], end diastolic volume [-6 (3) mL/m2, p < .05], and end systolic volume [-4 (1) mL/m2, p < .01] were significantly decreased in women compared with men. Likewise, diastolic function outcomes significantly worsened with age: E-wave velocity [-5 (2), p < .01], E/A ratio [-0.23 (0.08), p < .01], and e’ velocity [lateral: -1.5 (0.3) cm/s, p < .001; septal: -0.9 (0.2), p < .001] decreased with age while A-wave velocity [5 (1) cm/s, p < .001] and isovolumic relaxation time [6 (3) ms, p < .05] increased with age. Women demonstrated significantly decreased cardiac size and volumes compared with men, but there was no biological relationship to dysfunction. Moreover, individuals were within the range of ASE-defined healthy values with no evidence of systolic or diastolic function and no meaningful relationship to level, severity, or duration of injury. Decreases to left ventricular dimensions and mass seen in spinal cord injury may result from adaptation rather than maladaptive myocardial remodeling, and increased incidence of cardiovascular disease may be related to modifiable risk factors.
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21
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Järve A, Qadri F, Todiras M, Schmolke S, Bader M. Angiotensin-II receptor type Ia does not contribute to cardiac atrophy following high-thoracic spinal cord injury in mice. Exp Physiol 2020; 105:1316-1325. [PMID: 32515106 DOI: 10.1113/ep088378] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Accepted: 06/03/2020] [Indexed: 12/27/2022]
Abstract
NEW FINDINGS What is the central question of this study? What is the role of the renin-angiotensin system with angiotensin II acting via its receptor AT1a in spinal cord injury-induced cardiac atrophy? What is the main finding and its importance? Knockout of AT1a did not protect mice that had undergone thoracic level 4 transection from cardiac atrophy. There were no histopathological signs but there was reduced load-dependent left ventricular function (lower stroke volume and cardiac output) with preserved ejection fraction. ABSTRACT Spinal cord injury (SCI) leads to cardiac atrophy often accompanied by functional deficits. The renin-angiotensin system (RAS) with angiotensin II (AngII) signalling via its receptor AT1a might contribute to cardiac atrophy post-SCI. We performed spinal cord transection at thoracic level T4 (T4-Tx) or sham-operation in female wild-type mice (WT, n = 27) and mice deficient in AT1a (Agtr1a-/- , n = 27). Echocardiography (0, 7, 21 and 28 days post-SCI) and histology and gene expression analyses at 1 and 2 months post-SCI were performed. We found cardiac atrophy post-SCI: reduced heart weight, reduced estimated left ventricular mass in Agtr1a-/- , and reduced cardiomyocyte diameter in WT mice. Although, the latter as well as stroke volume (SV) and cardiac output (CO) were reduced in Agtr1a-/- mice already at baseline, cardiomyocyte diameter was even smaller in injured Agtr1a-/- mice compared to injured WT mice. SV and CO were reduced in WT mice post-SCI. Ejection fraction and fractional shortening were preserved post-SCI in both genotypes. There were no histological signs of fibrosis and pathology in the cardiac sections of either genotype post-SCI. Gene expression of Agtr1a showed a trend for up-regulation at 2 months post-SCI; angiotensinogen was up-regulated at 2 month post-SCI in both genotypes. AngII receptor type 2 (Agtr2) was up- and down-regulated at 1 and 2 months post-SCI in WT mice, respectively, and Ang-(1-7) receptor (Mas) at 1 and 2 months post-SCI. Atrogin-1/MAFbx and MuRF1, atrophy markers, were not significantly up-regulated post-SCI. Our data show that lack of AT1a does not protect from cardiac atrophy post-SCI.
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Affiliation(s)
- Anne Järve
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Berlin, Berlin, Germany
| | - Fatimunnisa Qadri
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Mihail Todiras
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.,Nicolae Testemițanu State University of Medicine and Pharmacy, Chisinau, Moldova
| | - Shirley Schmolke
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Michael Bader
- Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Berlin, Berlin, Germany.,Charité Universitätsmedizin Berlin, Berlin, Germany.,Institute for Biology, University of Lübeck, Lübeck, Germany
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22
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Sachdeva R, Krassioukov AV, Bucksot JE, Hays SA. Acute Cardiovascular Responses to Vagus Nerve Stimulation after Experimental Spinal Cord Injury. J Neurotrauma 2020; 37:1149-1155. [PMID: 31973660 DOI: 10.1089/neu.2019.6828] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Pairing vagus nerve stimulation (VNS) with rehabilitation has emerged as a potential strategy to enhance plasticity and improve recovery in a range of neurological disorders. A recent study highlights the therapeutic promise of VNS in promoting motor recovery after spinal cord injury (SCI). We investigated the safety of acute VNS in a rat model of chronic SCI. We measured the cardiovascular response to various VNS paradigms following chronic high-thoracic SCI that is known to deleteriously impact cardiovascular control. Dose-response experiments with continuous VNS revealed an SCI-dependent increase in sensitivity for heart rate (HR) and blood pressure (BP) compared with controls. A clinically relevant intermittent VNS resulted in transient reduction in HR in rats with SCI; however, BP remained unaltered. In all experiments, the effect lasted only while the VNS stimulus train was present, as HR and BP restored to baseline values as soon as VNS ended. No prolonged episodes of persisting hypotension were seen in either group. Further, VNS did not trigger autonomic dysreflexia or exacerbate the severity of autonomic dysreflexia when induced during or after stimulation sessions. Overall, these findings provide initial evidence that intermittent VNS at parameters used for targeted plasticity therapy (30 Hz, 0.8 mA) appears safe and supports further investigation of this potential therapy for use following SCI.
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Affiliation(s)
- Rahul Sachdeva
- International Collaboration on Repair Discoveries (ICORD), Division of Physical Medicine and Rehabilitation, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Medicine, Division of Physical Medicine and Rehabilitation, University of British Columbia, Vancouver, British Columbia, Canada
| | - Andrei V Krassioukov
- International Collaboration on Repair Discoveries (ICORD), Division of Physical Medicine and Rehabilitation, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Medicine, Division of Physical Medicine and Rehabilitation, University of British Columbia, Vancouver, British Columbia, Canada.,G.F. Strong Rehabilitation Center, Vancouver Coastal Health, Vancouver, British Columbia, Canada
| | - Jesse E Bucksot
- Erik Jonsson School of Engineering and Computer Science, The University of Texas at Dallas, Richardson, Texas, USA
| | - Seth A Hays
- Erik Jonsson School of Engineering and Computer Science, The University of Texas at Dallas, Richardson, Texas, USA.,Texas Biomedical Device Center, The University of Texas at Dallas, Richardson, Texas, USA.,School of Behavioral Brain Sciences, The University of Texas at Dallas, Richardson, Texas, USA
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Attenuation of autonomic dysreflexia during functional electrical stimulation cycling by neuromuscular electrical stimulation training: case reports. Spinal Cord Ser Cases 2020; 6:12. [PMID: 32127515 DOI: 10.1038/s41394-020-0262-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 02/12/2020] [Accepted: 02/15/2020] [Indexed: 11/08/2022] Open
Abstract
INTRODUCTION Spinal cord injury (SCI) may cause impairments of the motor, sensory, and autonomic nervous systems, which result in adverse changes in body composition and cardiovascular health. Functional electrical stimulation (FES) cycling may provide an effective alternative approach to perform exercise and improve cardiovascular health after SCI. Persons with an injury at or above T6 level are at high risk of developing a life-threatening complication of autonomic dysreflexia (AD). CASE PRESENTATION Two participants with motor-complete C6 SCI completed either 12 weeks of passive range of motion or surface neuromuscular electrical stimulation (NMES) resistance training, followed by 12 weeks of functional electrical stimulation (FES) lower extremity cycling for both participants. Systolic and diastolic blood pressure (BP) were measured to determine the effects of NMES-resistance training and FES-lower extremity cycling during rest and exercise. DISCUSSION The difference between mean value of BP during FES-lower extremity cycling exercise and resting BP averaged for 24 sessions was smaller for participant A (31.25 mmHg for systolic BP and 10.44 mmHg for diastolic BP), who received NMES-resistance training, as compared with participant B (58.62 mmHg for systolic BP and 35.07 mmHg for diastolic BP). The results of these case reports suggest that 12 weeks of NMES-resistance training preceding FES-lower extremity cycling may attenuate the development of AD after SCI. Risk of AD, triggered by noxious stimuli, may be dampened with FES-lower extremity cycling training in persons with SCI.
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Abstract
Context/Objective Autonomic dysreflexia is a clinical syndrome affecting persons with spinal cord lesions. The aim of the study was to detect the level of knowledge among students about autonomic dysreflexia in persons with spinal cord lesions.Design: Single centre questionnaire study.Setting: Faculty of Health Studies, Rijeka, Croatia.Participants Nursing (n = 43) and physiotherapy (n = 48) students.Outcome Measures: AD knowledge test.Results: More of the half of the students (57%) had contact with persons with spinal cord lesions during work, especially nursing students. The self-estimated knowledge of autonomic dysreflexia was judged as poor or none in 73.6% of students. On the autonomic dysreflexia knowledge test, nursing students collected mean of 5.6 points and physiotherapy students 4.9 points (P = 0.173). There was no difference in the autonomic dysreflexia test results regardless of work experience or group affiliation.Conclusion: The level of knowledge about autonomic dysreflexia among students was low. Our results suggest the need for more education of students and health care professionals to apply adequate treatment to persons with episodes of autonomic dysreflexia.
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Affiliation(s)
- Nada Strčić
- Faculty of Health Studies, University of Rijeka, Rijeka, Croatia,Special Hospital Medico, Rijeka, Croatia
| | - Dean Markić
- Faculty of Medicine, University of Rijeka, Rijeka, Croatia,Department of Urology, University Hospital Rijeka, Rijeka, Croatia,Correspondence to: Dean Markić, Department of Urology, University Hospital Rijeka, Tome Strižića 3, 51 000 Rijeka, Croatia.
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25
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Associations between arterial stiffness and blood pressure fluctuations after spinal cord injury. Spinal Cord 2019; 57:1057-1063. [DOI: 10.1038/s41393-019-0316-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 04/24/2019] [Accepted: 05/02/2019] [Indexed: 12/20/2022]
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26
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Saleem S, Sarafis ZK, Lee AHX, Squair JW, Barak OF, Sober-Williams E, Suraj R, Coombs GB, Mijacika T, West CR, Krassioukov AV, Ainslie PN, Dujic Z, Tzeng YC, Phillips AA. Spinal Cord Disruption Is Associated with a Loss of Cushing-Like Blood Pressure Interactions. J Neurotrauma 2019; 36:1487-1490. [PMID: 30458117 DOI: 10.1089/neu.2018.5931] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The capacity of the cerebrovasculature to buffer changes in blood pressure (BP) likely plays an important role in the prevention of stroke, which is three- to fourfold more common after spinal cord injury (SCI). Although the directional relationship between BP and cerebral blood flow (CBF) has traditionally been thought to travel solely from BP to CBF, a Cushing-like mechanism functioning in the inverse direction, in which changes in CBF influence BP, has recently been revealed using Granger causality analysis. Although both CBF buffering of BP and the Cushing-like mechanism are influenced by the sympathetic nervous system, we do not understand the impact of disruption of descending sympathetic pathways within the spinal cord, caused by cervical SCI on these regulatory systems. We hypothesized that people with cervical SCI would have greater BP to CBF transmission, as well as a reduced Cushing-like mechanism. The directional relationships between mean arterial BP (MAP; Finometer® PRO) and middle cerebral artery blood velocity (MCAv; transcranial Doppler) were assessed at rest in 14 cervical SCI subjects and 16 uninjured individuals using Granger causality analysis, while also accounting for end-tidal CO2 tension. Those with SCI exhibited 66% increased forward MAP→MCAv information transmission as compared with the uninjured group (p = 0.0003), indicating reduced cerebrovascular buffering of BP, and did not have a predominant backward Cushing-like MCAv→MAP phenotype. These results indicate that both forward and backward communication between BP and CBF are influenced by SCI, which may be associated with impaired cerebrovascular BP buffering after SCI as well as widespread BP instability.
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Affiliation(s)
- Saqib Saleem
- 1 Department of Electrical & Computer Engineering, COMSATS University Islamabad, Sahiwal, Pakistan
| | - Zoe K Sarafis
- 2 International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Amanda H X Lee
- 2 International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,3 Experimental Medicine Program, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jordan W Squair
- 2 International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,3 Experimental Medicine Program, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,5 MD/PhD Training Program, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.,4 Departments of Physiology and Pharmacology, Cardiac Sciences & Clinical Neurosciences, Libin Cardiovascular Institute of Alberta, Hotchkiss Brain Institute, University of Calgary, Foothills Calgary, Alberta, Canada
| | - Otto F Barak
- 6 Faculty of Medicine, University of Novi Sad, Novi Sad, Republic of Serbia.,7 Faculty of Sport and Physical Education, University of Novi Sad, Novi Sad, Republic of Serbia
| | - Elin Sober-Williams
- 4 Departments of Physiology and Pharmacology, Cardiac Sciences & Clinical Neurosciences, Libin Cardiovascular Institute of Alberta, Hotchkiss Brain Institute, University of Calgary, Foothills Calgary, Alberta, Canada
| | - Rejitha Suraj
- 4 Departments of Physiology and Pharmacology, Cardiac Sciences & Clinical Neurosciences, Libin Cardiovascular Institute of Alberta, Hotchkiss Brain Institute, University of Calgary, Foothills Calgary, Alberta, Canada
| | - Geoff B Coombs
- 8 Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Tanja Mijacika
- 9 Department of Integrative Physiology, University of Split School of Medicine, Split, Croatia
| | - Christopher R West
- 2 International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Andrei V Krassioukov
- 2 International Collaboration on Repair Discoveries, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Philip N Ainslie
- 8 Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, University of British Columbia, Kelowna, British Columbia, Canada
| | - Zeljko Dujic
- 9 Department of Integrative Physiology, University of Split School of Medicine, Split, Croatia
| | - Yu-Chieh Tzeng
- 10 Wellington Medical Technology Group, Department of Surgery and Anaesthesia, University of Otago, Wellington, New Zealand
| | - Aaron A Phillips
- 4 Departments of Physiology and Pharmacology, Cardiac Sciences & Clinical Neurosciences, Libin Cardiovascular Institute of Alberta, Hotchkiss Brain Institute, University of Calgary, Foothills Calgary, Alberta, Canada
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27
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Reynolds CA, O'Leary DS, Ly C, Smith SA, Minic Z. Development of a decerebrate model for investigating mechanisms mediating viscero-sympathetic reflexes in the spinalized rat. Am J Physiol Heart Circ Physiol 2019; 316:H1332-H1340. [PMID: 30875256 DOI: 10.1152/ajpheart.00724.2018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Autonomic dysreflexia (AD) often occurs in individuals living with spinal cord injury (SCI) and is characterized by uncontrolled hypertension in response to otherwise innocuous stimuli originating below the level of the spinal lesion. Visceral stimulation is a predominant cause of AD in humans and effectively replicates the phenotype in rodent models of SCI. Direct assessment of sympathetic responses to viscerosensory stimulation in spinalized animals is challenging and requires invasive surgical procedures necessitating the use of anesthesia. However, administration of anesthesia markedly affects viscerosensory reactivity, and the effects are exacerbated following spinal cord injury (SCI). Therefore, the major goal of the present study was to develop a decerebrate rodent preparation to facilitate quantification of sympathetic responses to visceral stimulation in the spinalized rat. Such a preparation enables the confounding effect of anesthesia to be eliminated. Sprague-Dawley rats were subjected to SCI at the fourth thoracic segment. Four weeks later, renal sympathetic nerve activity (RSNA) responses to visceral stimuli were quantified in urethane/chloralose-anesthetized and decerebrate preparations. Visceral stimulation was elicited via colorectal distension (CRD) for 1 min. In the decerebrate preparation, CRD produced dose-dependent increases in mean arterial pressure (MAP) and RSNA and dose-dependent decreases in heart rate (HR). These responses were significantly greater in magnitude among decerebrate animals when compared with urethane/chloralose-anesthetized controls and were markedly attenuated by the administration of urethane/chloralose anesthesia after decerebration. We conclude that the decerebrate preparation enables high-fidelity quantification of neuronal reactivity to visceral stimulation in spinalized rats. NEW & NOTEWORTHY In animal models commonly used to study spinal cord injury, quantification of sympathetic responses is particularly challenging due to the increased susceptibility of spinal reflex circuits to the anesthetic agents generally required for experimentation. This constitutes a major limitation to understanding the mechanisms mediating regionally specific neuronal responses to visceral activation in chronically spinalized animals. In the present study, we describe a spinalized, decerebrate rodent preparation that facilitates quantification of sympathetic reactivity in response to visceral stimuli following spinal cord injury. This preparation enables reliable and reproducible quantification of viscero-sympathetic reflex responses resembling those elicited in conscious animals and may provide added utility for preclinical evaluation of neuropharmacological agents for the management of autonomic dysreflexia.
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Affiliation(s)
- Christian A Reynolds
- Department of Emergency Medicine, Wayne State University School of Medicine , Detroit, Michigan.,Cardiovascular Research Institute, Wayne State University School of Medicine , Detroit, Michigan
| | - Donal S O'Leary
- Cardiovascular Research Institute, Wayne State University School of Medicine , Detroit, Michigan.,Department of Physiology, Wayne State University School of Medicine , Detroit, Michigan
| | - Cheng Ly
- Department of Statistical Sciences and Operations Research, Virginia Commonwealth University , Richmond, Virginia
| | - Scott A Smith
- Department of Internal Medicine, University of Texas Southwestern Medical Center , Dallas, Texas.,Department of Health Care Sciences, University of Texas Southwestern Medical Center , Dallas, Texas
| | - Zeljka Minic
- Department of Emergency Medicine, Wayne State University School of Medicine , Detroit, Michigan.,Cardiovascular Research Institute, Wayne State University School of Medicine , Detroit, Michigan
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28
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Alam M, Li S, Ahmed RU, Yam YM, Thakur S, Wang XY, Tang D, Ng S, Zheng YP. Development of a battery-free ultrasonically powered functional electrical stimulator for movement restoration after paralyzing spinal cord injury. J Neuroeng Rehabil 2019; 16:36. [PMID: 30850027 PMCID: PMC6408863 DOI: 10.1186/s12984-019-0501-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 02/22/2019] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Functional electrical stimulation (FES) is used to restore movements in paretic limbs after severe paralyses resulting from neurological injuries such as spinal cord injury (SCI). Most chronic FES systems utilize an implantable electrical stimulator to deliver a small electric current to the targeted muscle or nerve to stimulate muscle contractions. These implanted stimulators are generally bulky, mainly due to the size of the batteries. Furthermore, these battery-powered stimulators are required to be explanted every few years for battery replacement which may result in surgical failures or infections. Hence, a wireless power transfer technique is desirable to power these implantable stimulators. METHODS Conventional wireless power transduction faces significant challenges for safe and efficient energy transfer through the skin and deep into the body. Inductive and electromagnetic power transduction is generally used for very short distances and may also interfere with other medical measurements such as X-ray and MRI. To address these issues, we have developed a wireless, ultrasonically powered, implantable piezoelectric stimulator. The stimulator is encapsulated with biocompatible materials. RESULTS The stimulator is capable of harvesting a maximum of 5.95 mW electric power at an 8-mm depth under the skin from an ultrasound beam with about 380 mW/cm2 of acoustic intensity. The stimulator was implanted in several paraplegic rats with SCI. Our implanted stimulator successfully induced several hindlimb muscle contractions and restored leg movement. CONCLUSIONS A battery-free miniature (10 mm diameter × 4 mm thickness) implantable stimulator, developed in the current study is capable of directly stimulating paretic muscles through external ultrasound signals. The required cost to develop the stimulator is relatively low as all the components are off the shelf.
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Affiliation(s)
- Monzurul Alam
- Department of Biomedical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China
| | - Shuai Li
- Department of Biomedical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China
| | - Rakib Uddin Ahmed
- Department of Biomedical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China
| | - Yat Man Yam
- Department of Biomedical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China
| | - Suman Thakur
- Department of Chemical Sciences, Tezpur University, Tezpur, 784028 India
| | - Xiao-Yun Wang
- Guangdong Work Injury Rehabilitation Center, Guangzhou, China
| | - Dan Tang
- Guangdong Work Injury Rehabilitation Center, Guangzhou, China
| | - Serena Ng
- Community Rehabilitation Service Support Centre, Hospital Authority, Hong Kong SAR, China
| | - Yong-Ping Zheng
- Department of Biomedical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR, China
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29
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Squair JW, Ruiz I, Phillips AA, Zheng MM, Sarafis ZK, Sachdeva R, Gopaul R, Liu J, Tetzlaff W, West CR, Krassioukov AV. Minocycline Reduces the Severity of Autonomic Dysreflexia after Experimental Spinal Cord Injury. J Neurotrauma 2018; 35:2861-2871. [DOI: 10.1089/neu.2018.5703] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Jordan W. Squair
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- MD/PhD Training Program, University of British Columbia, Vancouver, British Columbia, Canada
| | - Ian Ruiz
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
| | - Aaron A. Phillips
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
| | - Mei M.Z. Zheng
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
| | - Zoe K. Sarafis
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
| | - Rahul Sachdeva
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
| | - Rayshad Gopaul
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jie Liu
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
| | - Wolfram Tetzlaff
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Zoology, Faculty of Science, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Surgery, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Christopher R. West
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Andrei V. Krassioukov
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Medicine, Division of Physical Medicine and Rehabilitation, University of British Columbia, Vancouver, British Columbia, Canada
- GF Strong Rehabilitation Centre, Vancouver Health Authority, Vancouver, British Columbia, Canada
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30
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Williams AM, Gee CM, Voss C, West CR. Cardiac consequences of spinal cord injury: systematic review and meta-analysis. Heart 2018; 105:217-225. [PMID: 30262456 DOI: 10.1136/heartjnl-2018-313585] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2018] [Revised: 08/23/2018] [Accepted: 08/25/2018] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE Conduct a meta-analysis to determine the impact of traumatic spinal cord injury (SCI) on echocardiographic measurements of left ventricular (LV) structure and function. METHODS MEDLINE and Embase were used for primary searches of studies reporting LV echocardiographic data in individuals with SCI. Of 378 unique citations, 36 relevant full-text articles were retrieved, and data from 27 studies were extracted for meta-analyses. Literature searches, article screening and data extraction were completed by two independent reviewers and compared for agreement. Primary analyses compared echocardiographic indices between individuals with SCI and able-bodied individuals, using a random effects model. RESULTS Data are reported as pooled effect estimates (95% CI). Data from 22 articles (474 participants) were included in the primary meta-analysis. Compared with able-bodied individuals, individuals with SCI had reductions to LV stroke volume of 11.8 mL (95% CI -17.8 to -5.9, p<0.001), end-diastolic volume of 19.6 mL (95% CI -27.2 to -11.9, p<0.001) and LV massindex of -7.7 g/m2 (95% CI -11.6 to -3.8, p<0.001), but ejection fraction was not different between the groups (95% CI -2.6% to 0.6%, p=0.236). Individuals with SCI also had altered indices of diastolic function, specifically a lowered ratio of early-to-late filling velocities (p=0.039), and augmented ratio of early diastolic flow-to-tissue velocities (p=0.021). CONCLUSIONS Individuals with SCI have smaller LV volumes and mass, and altered systolic and diastolic function. While this meta-analysis demonstrates important alterations to echocardiographic measures of cardiac structure and function at rest, future work should consider the impacts of SCI on the heart's capacity or 'reserve' to respond to physiological challenges. PROSPERO REGISTRATION NUMBER CRD42017072333.
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Affiliation(s)
- Alexandra Mackenzie Williams
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada.,Department of Cellular and Physiological Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Cameron Marshall Gee
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada.,Faculty of Education, School of Kinesiology, Vancouver, British Columbia, Canada
| | - Christine Voss
- Department of Pediatrics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Christopher Roy West
- International Collaboration on Repair Discoveries (ICORD), University of British Columbia, Vancouver, British Columbia, Canada.,Department of Cellular and Physiological Sciences, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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31
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Poormasjedi-Meibod MS, Mansouri M, Fossey M, Squair JW, Liu J, McNeill JH, West CR. Experimental Spinal Cord Injury Causes Left-Ventricular Atrophy and Is Associated with an Upregulation of Proteolytic Pathways. J Neurotrauma 2018; 36:950-961. [PMID: 29877162 DOI: 10.1089/neu.2017.5624] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Spinal cord injury (SCI) causes autonomic dysfunction, altered neurohumoral control, profound hemodynamic changes, and an increased risk of heart disease. In this prospective study, we investigated the cardiac consequences of chronic experimental SCI in rats by combining cutting edge in vivo techniques (magnetic resonance imaging [MRI] and left-ventricular [LV] pressure-volume catheterization) with histological and molecular assessments. Twelve weeks post-SCI, MRI-derived structural indices and in vivo LV catheterization-derived functional indices indicated the presence of LV atrophy (LV mass in Control vs. SCI = 525 ± 38.8 vs. 413 ± 28.6 mg, respectively; p = 0.0009), reduced ventricular volumes (left-ventricular end-diastolic volume in Control vs. SCI = 364 ± 44 vs. 221 ± 35 μL, respectively; p = 0.0004), and contractile dysfunction (end-systolic pressure-volume relationship in Control vs. SCI = 1.31 ± 0.31 vs. 0.76 ± 0.11 mm Hg/μL, respectively; p = 0.0045). Cardiac atrophy and contractile dysfunction in SCI were accompanied by significantly lower blood pressure, reduced circulatory norepinephrine, and increased angiotensin II. At the cellular level, we found the presence of reduced cardiomyocyte size and increased expression of angiotensin II type 1 receptors and transforming growth factor-beta receptors (TGF-β receptor 1 and 2) post-SCI. Importantly, we found more than a two-fold increase in muscle ring finger-1 and Beclin-1 protein level following SCI, indicating the upregulation of the ubiquitin-proteasome system and autophagy-lysosomal machinery. Our data provide novel evidence that SCI-induced cardiomyocyte atrophy and systolic cardiac dysfunction are accompanied by an upregulation of proteolytic pathways, the activation of which is likely due to loss of trophic support from the sympathetic nervous system, neuromechanical unloading, and altered neurohumoral pathways.
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Affiliation(s)
- Malihe-Sadat Poormasjedi-Meibod
- 1 International Collaboration on Repair Discoveries (ICORD), Vancouver, British Columbia, Canada.,2 School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Maral Mansouri
- 1 International Collaboration on Repair Discoveries (ICORD), Vancouver, British Columbia, Canada
| | - Mary Fossey
- 1 International Collaboration on Repair Discoveries (ICORD), Vancouver, British Columbia, Canada.,2 School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jordan W Squair
- 1 International Collaboration on Repair Discoveries (ICORD), Vancouver, British Columbia, Canada.,3 MD/PhD Training Program, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jie Liu
- 1 International Collaboration on Repair Discoveries (ICORD), Vancouver, British Columbia, Canada
| | - John H McNeill
- 4 Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Christopher R West
- 1 International Collaboration on Repair Discoveries (ICORD), Vancouver, British Columbia, Canada.,2 School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
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Squair JW, DeVeau KM, Harman KA, Poormasjedi-Meibod MS, Hayes B, Liu J, Magnuson DS, Krassioukov AV, West CR. Spinal Cord Injury Causes Systolic Dysfunction and Cardiomyocyte Atrophy. J Neurotrauma 2018; 35:424-434. [PMID: 28599602 PMCID: PMC9836687 DOI: 10.1089/neu.2017.4984] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Individuals with spinal cord injury (SCI) have been shown to exhibit systolic, and to a lesser extent, diastolic cardiac dysfunction. However, previous reports of cardiac dysfunction in this population are confounded by the changing loading conditions after SCI and as such, whether cardiac dysfunction per se is present is still unknown. Therefore, our aim was to establish if load-independent cardiac dysfunction is present after SCI, to understand the functional cardiac response to SCI, and to explore the changes within the cellular milieu of the myocardium. Here, we applied in vivo echocardiography and left-ventricular (LV) pressure-volume catheterization with dobutamine infusions to our Wistar rodent model of cardiac dysfunction 5 weeks following high (T2) thoracic contusion SCI, while also examining the morphological and transcriptional alterations of cardiomyocytes. We found that SCI significantly impairs systolic function independent of loading conditions (end-systolic elastance in control: 1.35 ± 0.15; SCI: 0.65 ± 0.19 mm Hg/μL). The reduction in contractile indices is accompanied by a reduction in width and length of cardiomyocytes as well as alterations in the LV extracellular matrix. Importantly, we demonstrate that the reduction in the rate (dP/dtmax) of LV pressure rise can be offset with beta-adrenergic stimulation, thereby experimentally implicating the loss of descending sympatho-excitatory control of the heart as a principle cause of LV dysfunction in SCI. Our data provide evidence that SCI induces systolic cardiac dysfunction independent of loading conditions and concomitant cardiomyocyte atrophy that may be underpinned by changes in the genes regulating the cardiac extracellular matrix.
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Affiliation(s)
- Jordan W. Squair
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- MD/PhD Training Program, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kathryn M. DeVeau
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky
| | - Kathryn A. Harman
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky
| | - Malihe-Sadat Poormasjedi-Meibod
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Brian Hayes
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jie Liu
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
| | - David S.K. Magnuson
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky
| | - Andrei V. Krassioukov
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Medicine, Division of Physical Medicine and Rehabilitation, University of British Columbia, Vancouver, British Columbia, Canada
- GF Strong Rehabilitation Centre, Vancouver Health Authority, Vancouver, British Columbia, Canada
| | - Christopher R. West
- International Collaboration on Repair Discoveries, University of British Columbia, Vancouver, British Columbia, Canada
- School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
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33
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Squair JW, Liu J, Tetzlaff W, Krassioukov AV, West CR. Spinal cord injury-induced cardiomyocyte atrophy and impaired cardiac function are severity dependent. Exp Physiol 2018; 103:179-189. [PMID: 29235182 DOI: 10.1113/ep086549] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Accepted: 11/13/2017] [Indexed: 12/30/2022]
Abstract
NEW FINDINGS What is the central question of this study? How does the severity of spinal cord injury affect left ventricular mechanics, function and the underlying cardiomyocyte morphology? What is the main finding and its importance? Here, we show that severe, but not moderate, spinal cord injury causes cardiomyocyte atrophy, altered left ventricular mechanics and impaired cardiac function. The principal aim of the present study was to assess how the severity of spinal cord injury (SCI) affects left ventricular (LV) mechanics, function and underlying cardiomyocyte morphology. Here, we used different severities of T3 spinal cord contusions (MODERATE, 200 kdyn contusion; SEVERE, 400 kdyn contusion; SHAM) and combined standard echocardiography with speckle tracking analyses to investigate in vivo cardiac function and deformation (contractility) after experimental SCI in the Wistar rat. In addition, we investigated changes in the intrinsic structure of cardiac myocytes ex vivo. We demonstrate that SEVERE SCI induces a characteristic decline in LV chamber size and a reduction in in vivo LV deformation (i.e. radial strain) throughout the entire systolic portion of the cardiac cycle [25.6 ± 3.0 versus 44.5 ± 8.1% (Pre-injury); P = 0.0029]. SEVERE SCI also caused structural changes in cardiomyocytes, including decreased length [115.6 ± 7.63 versus 125.8 ± 6.75 μm (SHAM); P = 0.0458], decreased width [7.78 ± 0.71 versus 10.78 ± 1.08 μm (SHAM); P = 0.0015] and an increase in the length/width ratio [14.88 ± 0.66 versus 11.74 ± 0.89 (SHAM); P = 0.0018], which was significantly correlated with LV flow-generating capacity after SCI (i.e. stroke volume, R2 = 0.659; P = 0.0013). Rats with MODERATE SCI exhibited no changes in any metric versus SHAM. This is the first study to demonstrate that the severity of SCI determines the course of changes in the intrinsic structure of cardiomyocytes, which are directly related to contractile function of the LV.
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Affiliation(s)
- Jordan W Squair
- International Collaboration of Repair Discoveries (ICORD), University of British Columbia, Vancouver, BC, Canada.,MD/PhD Training Program, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Jie Liu
- International Collaboration of Repair Discoveries (ICORD), University of British Columbia, Vancouver, BC, Canada
| | - Wolfram Tetzlaff
- International Collaboration of Repair Discoveries (ICORD), University of British Columbia, Vancouver, BC, Canada.,Department of Zoology, Faculty of Science, University of British Columbia, Vancouver, BC, Canada.,Department of Surgery, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - Andrei V Krassioukov
- International Collaboration of Repair Discoveries (ICORD), University of British Columbia, Vancouver, BC, Canada.,Department of Medicine, Division of Physical Medicine and Rehabilitation, University of British Columbia, Vancouver, BC, Canada.,GF Strong Rehabilitation Centre, Vancouver Health Authority, University of British Columbia, Vancouver, BC, Canada
| | - Christopher R West
- International Collaboration of Repair Discoveries (ICORD), University of British Columbia, Vancouver, BC, Canada.,School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
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DeVeau KM, Harman KA, Squair JW, Krassioukov AV, Magnuson DSK, West CR. A comparison of passive hindlimb cycling and active upper-limb exercise provides new insights into systolic dysfunction after spinal cord injury. Am J Physiol Heart Circ Physiol 2017; 313:H861-H870. [PMID: 28710067 PMCID: PMC9925118 DOI: 10.1152/ajpheart.00046.2017] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 07/05/2017] [Accepted: 07/12/2017] [Indexed: 12/24/2022]
Abstract
Active upper-limb and passive lower-limb exercise are two interventions used in the spinal cord injury (SCI) population. Although the global cardiac responses have been previously studied, it is unclear how either exercise influences contractile cardiac function. Here, the cardiac contractile and volumetric responses to upper-limb (swim) and passive lower-limb exercise were investigated in rodents with a severe high-thoracic SCI. Animals were divided into control (CON), SCI no exercise (NO-EX), SCI passive hindlimb cycling (PHLC), or SCI swim (SWIM) groups. Severe contusion SCI was administered at the T2 level. PHLC and SWIM interventions began on day 8 postinjury and lasted 25 days. Echocardiography and dobutamine stress echocardiography were performed before and after injury. Cardiac contractile indexes were assessed in vivo at study termination via a left ventricular pressure-volume conductance catheter. Stroke volume was reduced after SCI (91 µl in the NO-EX group vs. 188 µl in the CON group, P < 0.05) and was reversed at study termination in the PHLC (167 µl) but not SWIM (90 µl) group. Rates of contraction were reduced in NO-EX versus CON groups (6,079 vs. 9,225 mmHg, respectively, P < 0.05) and were unchanged by PHLC and SWIM training. Similarly, end-systolic elastance was reduced in the NO-EX versus CON groups (0.67 vs. 1.37 mmHg/µl, respectively, P < 0.05) and was unchanged by PHLC or SWIM training. Dobutamine infusion normalized all pressure indexes in each SCI group (all P < 0.05). In conclusion, PHLC improves flow-derived cardiac indexes, whereas SWIM training displayed no cardiobeneficial effect. Pressure-derived deficits were corrected only with dobutamine, suggesting that reduced β-adrenergic stimulation is principally responsible for the impaired cardiac contractile function after SCI.NEW & NOTEWORTHY This is the first direct comparison between the cardiac changes elicited by active upper-limb or passive lower-limb exercise after spinal cord injury. Here, we demonstrate that lower-limb exercise positively influences flow-derived cardiac indexes, whereas upper-limb exercise does not. Furthermore, neither intervention corrects the cardiac contractile dysfunction associated with spinal cord injury.
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Affiliation(s)
- Kathryn M. DeVeau
- 1International Collaboration on Repair Discoveries, Vancouver, British Columbia, Canada; ,2Kentucky Spinal Cord Injury Research Institute, University of Louisville, Louisville, Kentucky;
| | - Kathryn A. Harman
- 1International Collaboration on Repair Discoveries, Vancouver, British Columbia, Canada; ,2Kentucky Spinal Cord Injury Research Institute, University of Louisville, Louisville, Kentucky;
| | - Jordan W. Squair
- 1International Collaboration on Repair Discoveries, Vancouver, British Columbia, Canada; ,3MD/PhD Training Program, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada;
| | - Andrei V. Krassioukov
- 4Division of Physical Medicine and Rehabilitation, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada; ,5GF Strong Rehabilitation Centre, Vancouver Health Authority, Vancouver, British Columbia, Canada; and
| | - David S. K. Magnuson
- 2Kentucky Spinal Cord Injury Research Institute, University of Louisville, Louisville, Kentucky;
| | - Christopher R. West
- 1International Collaboration on Repair Discoveries, Vancouver, British Columbia, Canada; ,6School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
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Eldahan KC, Rabchevsky AG. Autonomic dysreflexia after spinal cord injury: Systemic pathophysiology and methods of management. Auton Neurosci 2017; 209:59-70. [PMID: 28506502 DOI: 10.1016/j.autneu.2017.05.002] [Citation(s) in RCA: 118] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 03/30/2017] [Accepted: 05/03/2017] [Indexed: 12/11/2022]
Abstract
Traumatic spinal cord injury (SCI) has widespread physiological effects beyond the disruption of sensory and motor function, notably the loss of normal autonomic and cardiovascular control. Injury at or above the sixth thoracic spinal cord segment segregates critical spinal sympathetic neurons from supraspinal modulation which can result in a syndrome known as autonomic dysreflexia (AD). AD is defined as episodic hypertension and concomitant baroreflex-mediated bradycardia initiated by unmodulated sympathetic reflexes in the decentralized cord. This condition is often triggered by noxious yet unperceived visceral or somatic stimuli below the injury level and if severe enough can require immediate medical attention. Herein, we review the pathophysiological mechanisms germane to the development of AD, including maladaptive plasticity of neural circuits mediating abnormal sympathetic reflexes and hypersensitization of peripheral vasculature that collectively contribute to abnormal hemodynamics after SCI. Further, we discuss the systemic effects of recurrent AD and pharmacological treatments used to manage such episodes. Contemporary research avenues are then presented to better understand the relative contributions of underlying mechanisms and to elucidate the effects of recurring AD on cardiovascular and immune functions for developing more targeted and effective treatments to attenuate the development of this insidious syndrome following high-level SCI.
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Affiliation(s)
- Khalid C Eldahan
- Department of Physiology, University of Kentucky, Lexington, KY 40536, United States; Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536, United States
| | - Alexander G Rabchevsky
- Department of Physiology, University of Kentucky, Lexington, KY 40536, United States; Spinal Cord and Brain Injury Research Center, University of Kentucky, Lexington, KY 40536, United States.
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Surgical Neurostimulation for Spinal Cord Injury. Brain Sci 2017; 7:brainsci7020018. [PMID: 28208601 PMCID: PMC5332961 DOI: 10.3390/brainsci7020018] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 01/30/2017] [Accepted: 02/02/2017] [Indexed: 01/07/2023] Open
Abstract
Traumatic spinal cord injury (SCI) is a devastating neurological condition characterized by a constellation of symptoms including paralysis, paraesthesia, pain, cardiovascular, bladder, bowel and sexual dysfunction. Current treatment for SCI involves acute resuscitation, aggressive rehabilitation and symptomatic treatment for complications. Despite the progress in scientific understanding, regenerative therapies are lacking. In this review, we outline the current state and future potential of invasive and non-invasive neuromodulation strategies including deep brain stimulation (DBS), spinal cord stimulation (SCS), motor cortex stimulation (MCS), transcutaneous direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS) in the context of SCI. We consider the ability of these therapies to address pain, sensorimotor symptoms and autonomic dysregulation associated with SCI. In addition to the potential to make important contributions to SCI treatment, neuromodulation has the added ability to contribute to our understanding of spinal cord neurobiology and the pathophysiology of SCI.
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