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Nunes KZ, Scorza FA, Cavalheiro EA, Vassallo DV. Reduction of vascular reactivity in rat aortas following pilocarpine-induced status epilepticus. Clinics (Sao Paulo) 2023; 78:100195. [PMID: 37099815 PMCID: PMC10149400 DOI: 10.1016/j.clinsp.2023.100195] [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: 10/06/2022] [Revised: 03/20/2023] [Accepted: 03/28/2023] [Indexed: 04/28/2023] Open
Abstract
OBJECTIVE The authors investigated changes in vascular reactivity in rats following pilocarpine-induced status epilepticus. METHOD Male Wistar rats weighing between 250g and 300g were used. Status epilepticus was induced using 385 mg/kg i.p. pilocarpine. After 40 days the thoracic aorta was dissected and divided into 4 mm rings and the vascular smooth muscle reactivity to phenylephrine was evaluated. RESULTS Epilepsy decreased the contractile responses of the aortic rings to phenylephrine (0.1 nM-300 mM). To investigate if this reduction was induced by increasing NO production with/or hydrogen peroxide L-NAME and Catalase were used. L-NAME (N-nitro-L arginine methyl ester) increased vascular reactivity but the contractile response to phenylephrine increased in the epileptic group. Catalase administration decreased the contractile responses only in the rings of rats with epilepsy. CONCLUSIONS Our findings demonstrated for the first time that epilepsy is capable of causing a reduction of vascular reactivity in rat aortas. These results suggest that vascular reactivity reduction is associated with increased production of Nitric Oxide (NO) as an organic attempt to avoid hypertension produced by excessive sympathetic activation.
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Affiliation(s)
- Karolini Zuqui Nunes
- Postgraduate Program in Nutrition and Health, Universidade Federal do Espírito Santo, Vitória, ES, Brazil.
| | - Fulvio Alexandre Scorza
- Discipline of Neuroscience, Universidade Federal de São Paulo/Escola Paulista de Medicina, São PauloSP, Brazil
| | - Esper Abrão Cavalheiro
- Discipline of Neuroscience, Universidade Federal de São Paulo/Escola Paulista de Medicina, São PauloSP, Brazil
| | - Dalton Valentim Vassallo
- Graduate Program in Physiological Sciences, Universidade Federal do Espírito Santo, Vitória, ES, Brazil
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Ibrahim A, Megahed A, Salem A, Zekry O. Impact of Cardiac Injury on the Clinical Outcome of Children with Convulsive Status Epilepticus. CHILDREN 2022; 9:children9020122. [PMID: 35204843 PMCID: PMC8869812 DOI: 10.3390/children9020122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 01/12/2022] [Accepted: 01/15/2022] [Indexed: 11/16/2022]
Abstract
Objectives: the aim of this study was to determine the impact of cardiac injury on clinical profile, cardiac evaluation and outcome in patients hospitalized with convulsive status epilepticus (CSE). Materials and methods: this prospective observational study included 74 children with CSE. Cardiac injury was evaluated and defined using combination of cardiac troponin, electrocardiography (ECG) and echocardiography. Clinical outcome and mortality rates were compared in patients with and without cardiac injury. Results: A total of 74 patients with CSE were included in the study. Thirty-six (48.6%) patients demonstrated markers of cardiac injury. ECG changes occurred in 45.9% and echocardiographic signs of left ventricular systolic and diastolic dysfunction reported in 5.4% and 8.1%, respectively. The mean length of hospital stays and need for ICU admission were significantly higher in patients with cardiac injury compared to others. One third of patients with cardiac injury needed mechanical ventilation and this was significantly higher than patients without (p = 0.042). hypotension and/or shock developed in 25% of cardiac injury patients and most of them required inotropic support; this was significantly higher than others without markers of cardiac injury. The overall mortality in cardiac injury group was higher (13.9% vs. 2.6%); however, this difference was not statistically significant. Conclusion: Markers of cardiac injury were common and associated with poor clinical outcome and higher risk of mortality in patients with CSE, so extensive routine cardiovascular evaluation is essential in these patients.
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Affiliation(s)
- Ahmed Ibrahim
- Department of Pediatrics, Faculty of Medicine, Suez Canal University, Ismailia 41511, Egypt; (A.M.); (O.Z.)
- Correspondence: ; Tel.: +20-1225951409
| | - Ahmed Megahed
- Department of Pediatrics, Faculty of Medicine, Suez Canal University, Ismailia 41511, Egypt; (A.M.); (O.Z.)
| | - Ahmed Salem
- Department of Cardiology, Faculty of Medicine, Suez Canal University, Ismailia 41511, Egypt;
| | - Osama Zekry
- Department of Pediatrics, Faculty of Medicine, Suez Canal University, Ismailia 41511, Egypt; (A.M.); (O.Z.)
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Deshpande LS, Blair RE, Halquist M, Kosmider L, DeLorenzo RJ. Intramuscular atenolol and levetiracetam reduce mortality in a rat model of paraoxon-induced status epilepticus. Ann N Y Acad Sci 2020; 1480:219-232. [PMID: 32961584 DOI: 10.1111/nyas.14500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Revised: 08/21/2020] [Accepted: 09/01/2020] [Indexed: 12/01/2022]
Abstract
Organophosphorus (OP) compounds are chemical threat agents and are irreversible inhibitors of the enzyme acetylcholinesterase that lead to a hypercholinergic response that could include status epilepticus (SE). SE particularly targets the heart and brain and despite existing therapies, it is still associated with significant mortality and morbidity. Here, we investigated the effect of intramuscular (i.m.) adjunct therapy consisting of atenolol (AT) and levetiracetam (LV) when administered after paraoxon (POX)-induced SE. The combination therapy was administered twice daily for 2, 7, or 14 days. POX exposure in rats produced rapid SE onset that was treated with atropine, pralidoxime chloride, and midazolam. Here, AT + LV therapy produced significant reductions in POX SE mortality assessed at 30 days post-SE. AT + LV therapy exhibited muscle pathology inflammation scores that were not significantly different from saline-treated controls. Pharmacokinetic analyses revealed that the i.m. route achieved faster and stabler plasma therapeutic levels for both AT and LV under OP SE conditions compared with oral administrations. Our data provide evidence of the safety and efficacy of i.m. AT + LV therapy for reducing mortality following POX SE.
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Affiliation(s)
- Laxmikant S Deshpande
- Department of Neurology, School of Medicine, Virginia Commonwealth University, Richmond, Virginia.,Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, Virginia
| | - Robert E Blair
- Department of Neurology, School of Medicine, Virginia Commonwealth University, Richmond, Virginia
| | - Matthew Halquist
- Department of Pharmaceutics, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia
| | - Leon Kosmider
- Department of Pharmaceutics, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia
| | - Robert J DeLorenzo
- Department of Neurology, School of Medicine, Virginia Commonwealth University, Richmond, Virginia.,Department of Pharmacology and Toxicology, School of Medicine, Virginia Commonwealth University, Richmond, Virginia
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Epilepsy and ultra-structural heart changes: The role of catecholaminergic toxicity and myocardial fibrosis. What can we learn from cardiology? Seizure 2019; 71:105-109. [PMID: 31306872 DOI: 10.1016/j.seizure.2019.07.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 06/10/2019] [Accepted: 07/01/2019] [Indexed: 12/24/2022] Open
Abstract
In this article, we explore the interaction of brain and heart in patients with epilepsy (PWE), focusing on new insights into possible pathways from epilepsy, catecholaminergic toxicity, subtle cardiac changes and sudden death. Initial evidence and biological plausibility point to an interaction between autonomic dysfunction, higher sympathetic drive, myocardial catecholaminergic toxicity and cardiac fibrosis resulting in subtle myocardial changes in structure, function, arrhythmogenesis and/or a heart failure-like phenotype in PWE. Non invasive imaging and biomarkers of cardiac injury and fibrosis are emerging as possible diagnostic tools to better stratify the risk of such individuals. Translational lessons from cardiac models of disease and ultra-structural lesions are used to support these considerations.
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Fialho GL, Wolf P, Walz R, Lin K. Increased cardiac stiffness is associated with autonomic dysfunction in patients with temporal lobe epilepsy. Epilepsia 2018; 59:e85-e90. [DOI: 10.1111/epi.14084] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/30/2018] [Indexed: 02/01/2023]
Affiliation(s)
- Guilherme L. Fialho
- Cardiology Division; Federal University of Santa Catarina (UFSC); Florianópolis SC Brazil
- Medical Sciences Postgraduate Program; Federal University of Santa Catarina (UFSC); Florianópolis SC Brazil
| | - Peter Wolf
- Medical Sciences Postgraduate Program; Federal University of Santa Catarina (UFSC); Florianópolis SC Brazil
- Neurology Division; Federal University of Santa Catarina (UFSC); Florianópolis SC Brazil
- Danish Epilepsy Center; Dianalund Denmark
| | - Roger Walz
- Medical Sciences Postgraduate Program; Federal University of Santa Catarina (UFSC); Florianópolis SC Brazil
- Neurology Division; Federal University of Santa Catarina (UFSC); Florianópolis SC Brazil
- Center for Applied Neurosciences (CeNAp); Federal University of Santa Catarina (UFSC); Florianópolis SC Brazil
| | - Katia Lin
- Medical Sciences Postgraduate Program; Federal University of Santa Catarina (UFSC); Florianópolis SC Brazil
- Neurology Division; Federal University of Santa Catarina (UFSC); Florianópolis SC Brazil
- Center for Applied Neurosciences (CeNAp); Federal University of Santa Catarina (UFSC); Florianópolis SC Brazil
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Inhibition of the prostaglandin receptor EP2 following status epilepticus reduces delayed mortality and brain inflammation. Proc Natl Acad Sci U S A 2013; 110:3591-6. [PMID: 23401547 DOI: 10.1073/pnas.1218498110] [Citation(s) in RCA: 130] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Prostaglandin E2 is now widely recognized to play critical roles in brain inflammation and injury, although the responsible prostaglandin receptors have not been fully identified. We developed a potent and selective antagonist for the prostaglandin E2 receptor subtype EP2, TG6-10-1, with a sufficient pharmacokinetic profile to be used in vivo. We found that in the mouse pilocarpine model of status epilepticus (SE), systemic administration of TG6-10-1 completely recapitulates the effects of conditional ablation of cyclooxygenase-2 from principal forebrain neurons, namely reduced delayed mortality, accelerated recovery from weight loss, reduced brain inflammation, prevention of blood-brain barrier opening, and neuroprotection in the hippocampus, without modifying seizures acutely. Prolonged SE in humans causes high mortality and morbidity that are associated with brain inflammation and injury, but currently the only effective treatment is to stop the seizures quickly enough with anticonvulsants to prevent brain damage. Our results suggest that the prostaglandin receptor EP2 is critically involved in neuroinflammation and neurodegeneration, and point to EP2 receptor antagonism as an adjunctive therapeutic strategy to treat SE.
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Tsai CY, Chan JYH, Hsu KS, Chang AYW, Chan SHH. Brain-derived neurotrophic factor ameliorates brain stem cardiovascular dysregulation during experimental temporal lobe status epilepticus. PLoS One 2012; 7:e33527. [PMID: 22442695 PMCID: PMC3307740 DOI: 10.1371/journal.pone.0033527] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Accepted: 02/14/2012] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Status epilepticus (SE) is an acute, prolonged epileptic crisis with a mortality rate of 20-30%; the underlying mechanism is not completely understood. We assessed the hypothesis that brain stem cardiovascular dysregulation occurs during SE because of oxidative stress in rostral ventrolateral medulla (RVLM), a key nucleus of the baroreflex loop; to be ameliorated by brain-derived neurotrophic factor (BDNF) via an antioxidant action. METHODOLOGY/PRINCIPAL FINDINGS In a clinically relevant experimental model of temporal lobe SE (TLSE) using Sprague-Dawley rats, sustained hippocampal seizure activity was accompanied by progressive hypotension that was preceded by a reduction in baroreflex-mediated sympathetic vasomotor tone; heart rate and baroreflex-mediated cardiac responses remained unaltered. Biochemical experiments further showed concurrent augmentation of superoxide anion, phosphorylated p47(phox) subunit of NADPH oxidase and mRNA or protein levels of BDNF, tropomyosin receptor kinase B (TrkB), angiotensin AT1 receptor subtype (AT1R), nitric oxide synthase II (NOS II) or peroxynitrite in RVLM. Whereas pretreatment by microinjection bilaterally into RVLM of a superoxide dismutase mimetic (tempol), a specific antagonist of NADPH oxidase (apocynin) or an AT1R antagonist (losartan) blunted significantly the augmented superoxide anion or phosphorylated p47(phox) subunit in RVLM, hypotension and the reduced baroreflex-mediated sympathetic vasomotor tone during experimental TLSE, pretreatment with a recombinant human TrkB-Fc fusion protein or an antisense bdnf oligonucleotide significantly potentiated all those events, alongside peroxynitrite. However, none of the pretreatments affected the insignificant changes in heart rate and baroreflex-mediated cardiac responses. CONCLUSIONS/SIGNIFICANCE We conclude that formation of peroxynitrite by a reaction between superoxide anion generated by NADPH oxidase in RVLM on activation by AT1R and NOS II-derived NO leads to a reduction in baroreflex-mediated sympathetic vasomotor tone during experimental TLSE; to be ameliorated by the upregulated BDNF/TrkB signaling via inhibition of p47(phox) phosphorylation. This information offers a new vista in devising therapeutic strategy towards minimizing mortality associated with TLSE.
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MESH Headings
- Acetophenones/pharmacology
- Animals
- Antioxidants/metabolism
- Brain Stem
- Brain-Derived Neurotrophic Factor
- Cardiovascular System/metabolism
- Cardiovascular System/physiopathology
- Cyclic N-Oxides/pharmacology
- Enzyme Inhibitors/pharmacology
- Epilepsy, Temporal Lobe/metabolism
- Epilepsy, Temporal Lobe/pathology
- Epilepsy, Temporal Lobe/physiopathology
- Epilepsy, Temporal Lobe/therapy
- Humans
- Losartan/pharmacology
- NADPH Oxidases/antagonists & inhibitors
- NADPH Oxidases/metabolism
- Nitric Oxide Synthase Type II/metabolism
- Oxidative Stress/drug effects
- Peroxynitrous Acid/metabolism
- Phosphorylation/drug effects
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptor, Angiotensin, Type 1/metabolism
- Receptor, trkB/antagonists & inhibitors
- Receptor, trkB/metabolism
- Spin Labels
- Status Epilepticus/metabolism
- Status Epilepticus/pathology
- Status Epilepticus/physiopathology
- Status Epilepticus/therapy
- Superoxides/metabolism
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Affiliation(s)
- Ching-Yi Tsai
- Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China
| | - Julie Y. H. Chan
- Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China
| | - Kuei-sen Hsu
- Department of Pharmacology, National Cheng Kung University, Tainan, Taiwan, Republic of China
| | - Alice Y. W. Chang
- Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China
- * E-mail: (AYWC); (SHHC)
| | - Samuel H. H. Chan
- Center for Translational Research in Biomedical Sciences, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan, Republic of China
- * E-mail: (AYWC); (SHHC)
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Abstract
Takotsubo cardiomyopathy is characterized by chest pain, dyspnea, electrocardiographic changes resembling an acute coronary syndrome, and transient wall-motion abnormalities without identifiable coronary culprit lesion explaining the wall-motion abnormality. Takotsubo cardiomyopathy occurs frequently after emotional or physical stress. Seizures have been reported as triggers of takotsubo cardiomyopathy. It is unknown if seizure-associated takotsubo cardiomyopathy differs from takotsubo cardiomyopathy associated with other triggers. Seizure-associated takotsubo cardiomyopathy cases from the literature were compared with takotsubo cardiomyopathy series comprising 30 or more patients. Thirty-six seizure-associated takotsubo cardiomyopathy cases (6 male, mean-age 61.5 years) were found. Seizure-type were tonic-clonic (n = 13), generalized (n = 5), status epilepticus (n = 6), grand mal (n = 2), or not reported (n = 13). Twelve patients had a history of epilepsy, in 15 patients takotsubo cardiomyopathy-associated seizure was the first or the information was not given (n = 9). In 17 patients takotsubo cardiomyopathy occurred immediately after the seizure, in 9 patients 1-72 h postictally, and in 10 patients, the interval was not reported. In 20 patients neurologic disorders were reported and in 14 psychiatric disorders were reported. There were medical comorbidities in 17 patients, arterial hypertension (n = 11), hyponatremia (n = 2), and cancer (n = 2). Compared with 974 patients reported in takotsubo cardiomyopathy -series, patients with seizure-associated takotsubo cardiomyopathy were younger (61.5 vs. 68.5 years, p < 0.0001), more frequently males (17 vs. 9%, p = 0.004), had less frequent chest pain (6 vs.76%, p < 0.005), more frequent cardiogenic shock (25 vs. 8%, p = 0.003), and more frequent recurrency (14 vs. 3%, p = 0.004). Seizure-associated takotsubo cardiomyopathy manifests frequently as sudden hemodynamic deterioration, which could result in death in the absence of adequate help. Probably some cases of sudden unexpected death in epilepsy are attributable to takotsubo cardiomyopathy.
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Bealer SL, Metcalf CS, Little JG. Methods for ECG evaluation of indicators of cardiac risk, and susceptibility to aconitine-induced arrhythmias in rats following status epilepticus. J Vis Exp 2011:2726. [PMID: 21505405 DOI: 10.3791/2726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Lethal cardiac arrhythmias contribute to mortality in a number of pathological conditions. Several parameters obtained from a non-invasive, easily obtained electrocardiogram (ECG) are established, well-validated prognostic indicators of cardiac risk in patients suffering from a number of cardiomyopathies. Increased heart rate, decreased heart rate variability (HRV), and increased duration and variability of cardiac ventricular electrical activity (QT interval) are all indicative of enhanced cardiac risk. In animal models, it is valuable to compare these ECG-derived variables and susceptibility to experimentally induced arrhythmias. Intravenous infusion of the arrhythmogenic agent aconitine has been widely used to evaluate susceptibility to arrhythmias in a range of experimental conditions, including animal models of depression and hypertension, following exercise and exposure to air pollutants, as well as determination of the antiarrhythmic efficacy of pharmacological agents. It should be noted that QT dispersion in humans is a measure of QT interval variation across the full set of leads from a standard 12-lead ECG. Consequently, the measure of QT dispersion from the 2-lead ECG in the rat described in this protocol is different than that calculated from human ECG records. This represents a limitation in the translation of the data obtained from rodents to human clinical medicine. Status epilepticus (SE) is a single seizure or series of continuously recurring seizures lasting more than 30 min, and results in mortality in 20% of cases. Many individuals survive the SE, but die within 30 days. The mechanism(s) of this delayed mortality is not fully understood. It has been suggested that lethal ventricular arrhythmias contribute to many of these deaths. In addition to SE, patients experiencing spontaneously recurring seizures, i.e. epilepsy, are at risk of premature sudden and unexpected death associated with epilepsy (SUDEP). As with SE, the precise mechanisms mediating SUDEP are not known. It has been proposed that ventricular abnormalities and resulting arrhythmias make a significant contribution. To investigate the mechanisms of seizure-related cardiac death, and the efficacy of cardioprotective therapies, it is necessary to obtain both ECG-derived indicators of risk and evaluate susceptibility to cardiac arrhythmias in animal models of seizure disorders. Here we describe methods for implanting ECG electrodes in the Sprague-Dawley laboratory rat (Rattus norvegicus), following SE, collection and analysis of ECG recordings, and induction of arrhythmias during iv infusion of aconitine. These procedures can be used to directly determine the relationships between ECG-derived measures of cardiac electrical activity and susceptibility to ventricular arrhythmias in rat models of seizure disorders, or any pathology associated with increased risk of sudden cardiac death.
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Affiliation(s)
- Steven L Bealer
- Department of Pharmacology and Toxicology, University of Utah, USA
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Huff JS, Fountain NB. Pathophysiology and definitions of seizures and status epilepticus. Emerg Med Clin North Am 2010; 29:1-13. [PMID: 21109098 DOI: 10.1016/j.emc.2010.08.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The pathophysiology of seizures is multifactorial and incompletely understood. Experimental work demonstrates that prolonged, abnormal, and excessive neuronal electrical activity in itself is injurious through several mechanisms independent of systemic acidosis and hypoxia. Population survival studies and laboratory investigations support the idea that brain injury and epileptogenesis result from status epilepticus. The basic distinction in seizure types is that of generalized and partial seizures. Correct classification of seizure types will aid in clinical communications and guide correct therapies. Revised definitions of generalized convulsive status epilepticus suggest making this diagnosis with as few as 5 minutes of continuous seizure activity.
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Affiliation(s)
- J Stephen Huff
- Department of Emergency Medicine, University of Virginia Health System, Box 800699, Charlottesville, VA 22908, USA.
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Bealer SL, Little JG, Metcalf CS, Brewster AL, Anderson AE. Autonomic and cellular mechanisms mediating detrimental cardiac effects of status epilepticus. Epilepsy Res 2010; 91:66-73. [PMID: 20650612 PMCID: PMC3212408 DOI: 10.1016/j.eplepsyres.2010.06.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 06/09/2010] [Accepted: 06/23/2010] [Indexed: 11/22/2022]
Abstract
Prolonged seizure activity (status epilepticus; SE) can result in increased susceptibility to lethal ventricular arrhythmias for an extended period of time following seizure termination. SE is accompanied by acute, intense activation of the sympathetic nervous system (SymNS) and results in myocyte myofilament damage, arrhythmogenic alterations in cardiac electrical activity, and increased susceptibility to ventricular arrhythmias. However, the mechanisms mediating the changes in cardiac function, and the specific arrhythmogenic substrate produced during SE are unknown. To determine if detrimental cardiac effects of SE are mediated by SymNS stimulation of the heart, we examined the effects of B-adrenergic blockade (atenolol) during seizure activity on blood pressure, heart rate, myocyte myofilament injury (cardiac troponin I, cTnI), electrocardiographic activity, and susceptibility to arrhythmias. Furthermore, we determined if SE was associated with altered expression of the Kv4.x potassium channels, which are critical for action potential repolarization and thereby contribute significantly to normal cardiac electrical activity. Lithium-pilocarpine induced SE was associated with acute tachycardia, hypertension, and cardiomyocyte damage. Arrhythmogenic alterations in cardiac electrical activity accompanied by increased susceptibility to experimentally induced arrhythmias were evident during the first 2 weeks following SE. Both were prevented by atenolol treatment during seizures. Furthermore, one and two weeks after SE, myocyte ion channel remodeling, characterized by a decreased expression of cardiac Kv4.2 potassium channels, was evident. These data suggest that the cardiac effects of prolonged and intense SymNS activation during SE induce myofilament damage and downregulation of Kv4.2 channels, which alter cardiac electrical activity and increase susceptibility to lethal arrhythmias.
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Affiliation(s)
- Steven L Bealer
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt Lake City, UT 84121, United States.
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12
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McMullan J, Sasson C, Pancioli A, Silbergleit R. Midazolam versus diazepam for the treatment of status epilepticus in children and young adults: a meta-analysis. Acad Emerg Med 2010; 17:575-82. [PMID: 20624136 DOI: 10.1111/j.1553-2712.2010.00751.x] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Rapid treatment of status epilepticus (SE) is associated with better outcomes. Diazepam and midazolam are commonly used, but the optimal agent and administration route is unclear. OBJECTIVES The objective was to determine by systematic review if nonintravenous (non-IV) midazolam is as effective as diazepam, by any route, in terminating SE seizures in children and adults. Time to seizure cessation and respiratory complications was examined. METHODS We performed a search of PubMed, Web of Knowledge, Embase, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, American College of Physicians Journal Club, Cochrane Central Register of Controlled Trials, the Cumulative Index to Nursing and Allied Health Literature, and International Pharmaceutical Abstracts for studies published January 1, 1950, through July 4, 2009. English language quasi-experimental or randomized controlled trials comparing midazolam and diazepam as first-line treatment for SE, and meeting the Consolidated Standards of Reporting Trials (CONSORT)-based quality measures, were eligible. Two reviewers independently screened studies for inclusion and extracted outcomes data. Administration routes were stratified as non-IV (buccal, intranasal, intramuscular, rectal) or IV. Fixed-effects models generated pooled statistics. RESULTS Six studies with 774 subjects were included. For seizure cessation, midazolam, by any route, was superior to diazepam, by any route (relative risk [RR] = 1.52; 95% confidence interval [CI] = 1.27 to 1.82). Non-IV midazolam is as effective as IV diazepam (RR = 0.79; 95% CI = 0.19 to 3.36), and buccal midazolam is superior to rectal diazepam in achieving seizure control (RR = 1.54; 95% CI = 1.29 to 1.85). Midazolam was administered faster than diazepam (mean difference = 2.46 minutes; 95% CI = 1.52 to 3.39 minutes) and had similar times between drug administration and seizure cessation. Respiratory complications requiring intervention were similar, regardless of administration route (RR = 1.49; 95% CI = 0.25 to 8.72). CONCLUSIONS Non-IV midazolam, compared to non-IV or IV diazepam, is safe and effective in treating SE. Comparison to lorazepam, evaluation in adults, and prospective confirmation of safety and efficacy is needed.
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Affiliation(s)
- Jason McMullan
- Department of Emergency Medicine, University of Cincinnati, Cincinnati, OH, USA.
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Metcalf CS, Poelzing S, Little JG, Bealer SL. Status epilepticus induces cardiac myofilament damage and increased susceptibility to arrhythmias in rats. Am J Physiol Heart Circ Physiol 2009; 297:H2120-7. [PMID: 19820194 DOI: 10.1152/ajpheart.00724.2009] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Status epilepticus (SE) is a seizure or series of seizures that persist for >30 min and often results in mortality. Death rarely occurs during or immediately following seizure activity, but usually within 30 days. Although ventricular arrhythmias have been implicated in SE-related mortality, the effects of this prolonged seizure activity on the cardiac function and susceptibility to arrhythmias have not been directly investigated. We evaluated myocardial damage, alterations in cardiac electrical activity, and susceptibility to experimentally induced arrhythmias produced by SE in rats. SE resulted in seizure-related increases in blood pressure, heart rate, and the first derivative of pressure, as well as modest, diffuse myocyte damage assessed by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling staining. Ten to twelve days following seizures, electrocardiographic recordings showed arrhythmogenic alterations in cardiac electrical activity, denoted by prolonged QT interval corrected for heart rate and QT dispersion. Finally, SE increased susceptibility to experimentally induced (intravenous aconitine) cardiac arrhythmias. These data suggest that SE produces tachycardic ischemia following the activation of the sympathetic nervous system, resulting in cardiac myofilament damage, arrhythmogenic alterations in cardiac electrical activity, and increased susceptibility to ventricular arrhythmias.
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Affiliation(s)
- Cameron S Metcalf
- Department of Pharmacology and Toxicology, University of Utah, 30 S. 2000 East Rm. 201, Salt Lake City, UT 84112, USA
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Metcalf CS, Radwanski PB, Bealer SL. Status epilepticus produces chronic alterations in cardiac sympathovagal balance. Epilepsia 2009; 50:747-54. [PMID: 18727681 DOI: 10.1111/j.1528-1167.2008.01764.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE Status epilepticus (SE) activates the autonomic nervous system, increasing sympathetic nervous system control of cardiac function during seizure activity. However, lasting effects of SE on autonomic regulation of the heart, which may contribute to mortality following seizure activity, are unknown. Therefore, autonomic control of cardiac function was assessed following SE. METHODS Using Sprague-Dawley rats after 1-2 weeks of recovery from lithium-pilocarpine-induced SE or control procedures, we tested overall sympathovagal control of the heart, the individual contributions of the sympathetic and parasympathetic components of the autonomic nervous system, and baroreflex sensitivity. RESULTS SE induced a chronic shift in sympathovagal balance toward sympathetic dominance resulting from decreased parasympathetic activity. Baroreflex sensitivity to increased blood pressure was also decreased, likely resulting from diminished vagal activation. DISCUSSION Chronic alterations in autonomic regulation of cardiac function, characterized by increased sympathetic dominance, occur following SE and likely contribute to subsequent increased cardiac risk and mortality.
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Affiliation(s)
- Cameron S Metcalf
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Utah, Salt Lake City, Utah, USA
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15
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Prise en charge non spécifique de l’état de mal épileptique convulsif. Rev Neurol (Paris) 2009; 165:348-54. [DOI: 10.1016/j.neurol.2008.11.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2008] [Accepted: 11/25/2008] [Indexed: 01/04/2023]
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16
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Blair RE, Deshpande LS, Holbert WH, Churn SB, DeLorenzo RJ. Age-dependent mortality in the pilocarpine model of status epilepticus. Neurosci Lett 2009; 453:233-7. [PMID: 19429042 DOI: 10.1016/j.neulet.2009.02.035] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2008] [Revised: 02/13/2009] [Accepted: 02/14/2009] [Indexed: 01/21/2023]
Abstract
Status epilepticus (SE) is an acute neurological emergency associated with significant morbidity and mortality. Age has been shown to be a critical factor in determining outcome after SE. Understanding the causes of this increased mortality with aging by developing an animal model to study this condition would play a major role in studying mechanisms to limit the mortality due to SE. Here we employed pilocarpine to induce SE in rats aged between 5 and 28 weeks. Similar to clinical studies in man, we observed that age was a significant predictor of mortality following SE. While no deaths were observed in 5-week-old animals, mortality due to SE increased progressively with age and reached 90% in 28-week-old animals. There was no correlation between the age of animals and severity of SE. With increasing age mortality occurred earlier after the onset of SE. These results indicate that pilocarpine-induced SE in the rat provides a useful model to study age-dependent SE-induced mortality and indicates the importance of using animal models to elucidate the mechanisms contributing to SE-induced mortality and the development of novel therapeutic interventions to prevent SE-induced death.
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Affiliation(s)
- Robert E Blair
- Department of Neurology, Virginia Commonwealth University, Richmond, VA 23298, USA
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17
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Asadi-Pooya AA, Poordast A. Etiologies and outcomes of status epilepticus in children. Epilepsy Behav 2005; 7:502-5. [PMID: 16146707 DOI: 10.1016/j.yebeh.2005.07.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2005] [Revised: 07/07/2005] [Accepted: 07/08/2005] [Indexed: 11/26/2022]
Abstract
PURPOSE Status epilepticus (SE) is a medical emergency with significant associated mortality and morbidity. This study was conducted to determine the etiology and outcome of SE in children. METHODS All patients from 1 month to 15 years old with SE admitted to Nemazee Hospital, Shiraz, Iran, the main pediatric hospital in the area, between 1999 and 2004, were studied in a retrospective cross-sectional study. Outcomes were rated according to the Glasgow Outcome Score (GOS). RESULTS In all, 135 patients (76 boys, 59 girls) were studied. The most common cause of SE was fever. Etiology of SE did not differ significantly between various age groups and also between boys and girls (P=0.736 and P=0.156, respectively). Fourteen patients died in hospital and 81 were discharged in good health. Outcome did not differ significantly between the age groups (P=0.695) or between boys and girls (P=0.386). When classified as good (GOS=5) and bad (GOS=1-4), outcome was significantly correlated with etiology of SE (P=0.017). Prolonged febrile seizures had the best, and symptomatic SE the worst, outcome. DISCUSSION In this study, even in children above 3 years of age, fever was the most common cause of SE. This is noteworthy and heralds the need to pay more attention to febrile seizures, especially in children at risk for their occurrence. Outcome was not related to age and sex, but etiology of SE significantly influenced outcome.
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18
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Manno EM, Pfeifer EA, Cascino GD, Noe KH, Wijdicks EFM. Cardiac pathology in status epilepticus. Ann Neurol 2005; 58:954-7. [PMID: 16240367 DOI: 10.1002/ana.20677] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Massive catecholamine release resulting in the formation of cardiac contraction bands may represent the cause of death in status epilepticus (SE). We reviewed the cardiac pathology of patients who died during SE to asses for contraction bands. Eight of 11 patients who died during SE had identifiable myocardial contraction bands compared with 5 of 22 control patients (p < 0.05, Fisher's exact t test). These findings delineate a pathological substrate and provide compelling evidence that excessive catecholamine release is the mechanism responsible for death in SE.
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Affiliation(s)
- Edward M Manno
- Department of Neurology W8B, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55905, USA.
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19
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Abstract
Status epilepticus (SE) has an annual incidence exceeding 100,000 cases in the United States alone, of which more than 20% result in death. Thus, increased awareness of presentation, etiologies, and treatment of SE is essential in the practice of critical care medicine. This review discusses current definitions of SE, as well as its clinical presentation and classification. The recent literature on epidemiology is reviewed, including morbidity and mortality data. An overview of the systemic pathophysiologic effects of SE is presented. Finally, significant studies on the treatment of acute SE and refractory SE are reviewed, including the use of anticonvulsants, such as benzodiazepines, and other drugs.
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Affiliation(s)
- Sarice Bassin
- Department of Neurology, University of Virginia, Charlottesville, Virginia, USA.
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20
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Abstract
Status epilepticus is common and associated with significant mortality and complications. It affects approximately 50 patients per 100,000 population annually and recurs in >13%. History of epilepsy is the strongest single risk factor for generalized convulsive status epilepticus. More than 15% of patients with epilepsy have at least one episode of status epilepticus and low antiepileptic drug levels are a potentially modifiable risk factor. Other risks include young age, genetic predisposition, and acquired brain insults. Fever is a very common risk in children, as is stroke in adults. Mortality rates are 15% to 20% in adults and 3% to 15% in children. Acute complications result from hyperthermia, pulmonary edema, cardiac arrhythmias, and cardiovascular collapse. Long-term complications include epilepsy (20% to 40%), encephalopathy (6% to 15%), and focal neurologic deficits (9% to 11%). Neuronal injury leading to temporal lobe epilepsy is probably mediated by excess excitation via activation of the N-methyl-D-aspartate (NMDA) subtype of glutamate receptors and consequent elevated intracellular calcium that causes acute necrosis and delayed apoptotic cell death. Some forms of nonconvulsive status epilepticus may also lead to neuronal injury by this mechanism, but others may not. Based on clinical and experimental observations, complex partial status epilepticus is more likely to result in neuronal injury similar to generalized convulsive status epilepticus. Absence status epilepticus is much less likely to result in neuronal injury, and complications because it may be mediated primarily through excess inhibition. Future research strategies to prevent complications of status epilepticus include the study of new drugs (including NMDA antagonists, new drug delivery systems, and drug combinations) to stop seizure activity and prevent acute and delayed neuronal injury that leads to the development of epilepsy.
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Affiliation(s)
- N B Fountain
- Department of Neurology, University of Virginia School of Medicine, Charlottesville, USA
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21
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Abstract
The outcome of status epilepticus (SE) depends on its cause, clinical presentation, duration, treatment, and the patient's age. It has been estimated that in nearly all cases (about 98%), mortality is directly or indirectly due to the underlying disorder. It is particularly significant in generalized tonic-clonic SE. The clinical presentation of SE is strongly cause-dependent, and its etiology is markedly age-dependent in infants, children, young adults and the elderly. When SE is of long duration, due to its etiology, delayed treatment, or inappropriate drug administration, it results in brain lesions and the accompanying risk of sequelae or death. The highest mortality rates in SE are those at the extremes of the average life-span, i.e., in infants and young children and in the elderly. Possible SE sequelae are neurologic deficits or cognitive impairment, and/or unprovoked seizures. The outcome in cases of SE has considerably improved due to the early prescription of effective antiepileptic drugs.
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Affiliation(s)
- P Loiseau
- Service de neurologie, hôpital Pellegrin, Bordeaux, France
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22
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Barakat O, Fernández Pérez M, Corrales Cruz J, González Fernández F, Izquierdo Ayuso G, Fajardo Gálvez J. Estado epiléptico. Med Intensiva 2000. [DOI: 10.1016/s0210-5691(00)79635-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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