Blood markers of cardiac stress after generalized convulsive seizures

Impaired brain-heart axis in focal epilepsy: Alterations in information flow and implications for seizure dynamics

This study delves into functional brain-heart interplay (BHI) dynamics during interictal periods before and after seizure events in focal epilepsy. Our analysis focuses on elucidating the causal interaction between cortical and autonomic nervous system (ANS) oscillations, employing electroencephalography and heart rate variability series. The dataset for this investigation comprises 47 seizure events from 14 independent subjects, obtained from the publicly available Siena Dataset. Our findings reveal an impaired brain-heart axis especially in the heart-to-brain functional direction. This is particularly evident in bottom-up oscillations originating from sympathovagal activity during the transition between preictal and postictal periods. These results indicate a pivotal role of the ANS in epilepsy dynamics. Notably, the brain-to-heart information flow targeting cardiac oscillations in the low-frequency band does not display significant changes. However, there are noteworthy changes in cortical oscillations, primarily originating in central regions, influencing heartbeat oscillations in the high-frequency band. Our study conceptualizes seizures as a state of hyperexcitability and a network disease affecting both cortical and peripheral neural dynamics. Our results pave the way for a deeper understanding of BHI in epilepsy, which holds promise for the development of advanced diagnostic and therapeutic approaches also based on bodily neural activity for individuals living with epilepsy.

Cardiac arrhythmia and epilepsy genetic variants in sudden unexpected death in epilepsy

Introduction

Sudden Unexpected Death in Epilepsy (SUDEP) is the leading epilepsy-related cause of death, affecting approximately 1 per 1,000 individuals with epilepsy per year. Genetic variants that affect autonomic function, such as genes associated with cardiac arrhythmias, may predispose people with epilepsy to greater risk of both sudden cardiac death and SUDEP. Advances in next generation sequencing allow for the exploration of gene variants as potential biomarkers.

Methods

Genetic testing for the presence of cardiac arrhythmia and epilepsy gene variants was performed via genetic panels in 39 cases of SUDEP identified via autopsy by the Ontario Forensic Pathology Service. Variants were summarized by in-silico evidence for pathogenicity from 4 algorithms (SIFT, PolyPhen-2, PROVEAN, Mutation Taster) and allele frequencies in the general population (GnomAD). A maximum credible population allele frequency of 0.00004 was calculated based on epilepsy prevalence and SUDEP incidence to assess whether a variant was compatible with a pathogenic interpretation.

Results

Median age at the time of death was 33.3 years (range: 2, 60). Fifty-nine percent (n=23) were male. Gene panels detected 62 unique variants in 45 genes: 19 on the arrhythmia panel and 26 on the epilepsy panel. At least one variant was identified in 28 (72%) of decedents. Missense mutations comprised 57 (92%) of the observed variants. At least three in silico models predicted 12 (46%) cardiac arrhythmia panel missense variants and 20 (65%) epilepsy panel missense variants were pathogenic. Population allele frequencies were <0.00004 for 11 (42%) of the cardiac variants and 10 (32%) of the epilepsy variants. Together, these metrics identified 13 SUDEP variants of interest.

Discussion

Nearly three-quarters of decedents in this SUDEP cohort carried variants in comprehensive epilepsy or cardiac arrhythmia gene panels, with more than a third having variants in both panels. The proportion of decedents with cardiac variants aligns with recent studies of the disproportionate cardiac burden the epilepsy community faces compared to the general population and suggests a possible cardiac contribution to epilepsy mortality. These results identified 13 priority targets for future functional studies of these genes potential role in sudden death and demonstrates the necessity for further exploration of potential genetic contributions to SUDEP.

Cardiac dysfunctions in children with drug-resistant epilepsy

Objective

There were reports of cardiac dysfunction that led to sudden unexpected death in epilepsy (SUDEP) in patients with epilepsy. Early detection of cardiac dysfunction can lead to early management to prevent sudden cardiac death in these patients. The objective of our study is to assess cardiac functions in children with drug-resistant epilepsy (DRE) compared with the normal population by using a standard echocardiogram (SE), tissue Doppler imaging (TDI) and myocardial strain evaluations (MSE).

Method

Twenty-seven children who have been diagnosed with DRE based on the International League against Epilepsy (ILAE) were included in the study, along with 27 children whose ages match those of the normal control group.

Results

Seventeen children, median age 12 years old, were using more than four anti-seizure medications. Structural brain lesions were the most common cause of epilepsy, 55.6% (15). Generalized tonic-clonic seizures were the most common seizure type, 55.6% (15). Children with DRE had a lower early mitral valve E wave inflow velocity compared with the control group (p < 0.05). They also had lowered early diastolic velocities (e') and myocardial performance index (MPI) when compared with the control group (p < 0.05). There was a statistically significant difference in left ventricular myocardial strain in children with DRE, with an average of -21.1 (IQR -23.5 and -19.4) and control, -25.5 (IQR -27.3 and -24.2).

Significance

Children with DRE have an impairment of left ventricular diastolic function and myocardial strain, which could indicate decreased myocardial deformation and contraction compared with controls. These cardiological assessments can be used to evaluate children with DRE for early diagnosis and management of their cardiac dysfunction.

Characteristics of deceased subjects transported to a postmortem imaging center due to unusual death related to epilepsy

OBJECTIVE

Patients with epilepsy have high risk of experiencing uncommon causes of death. This study aimed to evaluate patients who underwent unusual deaths related to epilepsy and identify factors that may contribute to these deaths and may also include sudden unexpected death in epilepsy (SUDEP).

METHODS

We analyzed 5291 cases in which a postmortem imaging (PMI) study was performed using plane CT, because of an unexplained death. A rapid troponin T assay was performed using peripheral blood samples. Clinical information including the cause of death suspected by the attending physician, body position, place of death, medical history, and antiseizure medications was evaluated.

RESULTS

A total of 132 (2.6%) patients had an obvious history of epilepsy, while 5159 individuals had no history of epilepsy (97.4%). Cerebrovascular disease was the cause of death in 1.6% of patients in the group with epilepsy, and this was significantly lower than that in the non-epilepsy group. However, drowning was significantly higher (9.1% vs. 4.4%). Unspecified cause of death was significantly more frequent in the epilepsy group (78.0% vs. 57.8%). Furthermore, the proportion of patients who demonstrated elevation of troponin T levels without prior cardiac disease was significantly higher in the epilepsy group (37.9% vs. 31.1%). At discovery of death, prone position was dominant (30.3%), with deaths occurring most commonly in the bedroom (49.2%). No antiseizure medication had been prescribed in 12% of cases, while 29.5% of patients were taking multiple antiseizure medications.

SIGNIFICANCE

The prevalence of epilepsy in individuals experiencing unusual death was higher than in the general population. Despite PMI studies, no definitive cause of death was identified in a significant proportion of cases. The high troponin T levels may be explained by long intervals between death and examination or by higher incidence of myocardial damage at the time of death.

PLAIN LANGUAGE SUMMARY

This study investigated unusual deaths in epilepsy patients, analyzing 5291 postmortem imaging cases. The results showed that 132 cases (2.6%) had a clear history of epilepsy. In these cases, only 22% cases were explained after postmortem examination, which is less than in non-epilepsy group (42.2%). Cerebrovascular disease was less common in the epilepsy group, while drowning was more common. Elevated troponin T levels, which suggest possibility of myocardial damage or long intervals between death and examination, were also more frequent in the epilepsy group compared to non-epilepsy group.

Unusual presentation of benzodiazepine withdrawal with Takotsubo syndrome: a case report

Background

Thousands of people suffer from anxiety, depression, and insomnia every day, with benzodiazepines being one of the strategies used to treat these conditions. Withdrawal from its long-term use can lead to potentially life-threatening complications, including Takotsubo syndrome. The authors highlight an atypical case of Takotsubo syndrome secondary to benzodiazepine withdrawal, a rare life-threatening complication of acute substance withdrawal.

Case summary

A 58-year-old female presented to the emergency department with altered mental status and acute pulmonary oedema after discontinuing her prescribed benzodiazepines 3 days prior to presentation. Electrocardiogram (ECG) demonstrated anterior ST-segment elevation, with Q-wave and T-wave inversion with prolonged QT interval. Troponin I concentration and B-type natriuretic peptide were elevated to 5407 ng/L (normal ≤ 16 ng/L) and to 1627.0 pg/L (normal ≤ 100 pg/mL), respectively. Echocardiogram showed ballooning of the left ventricle (LV) apex with dyskinesia of the mid and apical segments, with LV function of 15%. Coronary angiography was normal, but left ventriculography showed severe LV systolic dysfunction with akinesis of the mid and apical LV segments and hyperdynamic basal segments. A presumptive diagnosis of benzodiazepine withdrawal-induced Takotsubo syndrome was made, and patients' symptoms, ECG findings, and LV dysfunction resolved after benzodiazepine administration. Six months post discharge, the patient remained asymptomatic with a normal biventricular function, and a beta-blocker was successfully introduced as part of a lifelong plan.

Discussion

A diagnosis of benzodiazepine withdrawal-induced Takotsubo syndrome is an underrecognized and challenging diagnosis, due to its atypical clinical presentation. High degree of clinical suspicion for this syndrome is crucial, since favourable prognosis depends on prompt diagnosis and treatment.

Epilepsy and long-term risk of arrhythmias

BACKGROUND AND AIMS

Previous evidence has mainly supported transient changes in cardiac function during interictal or peri-ictal phases in people with epilepsy, but the long-term risk of cardiac arrhythmias is poorly described. This study aimed to assess the long-term association of epilepsy with cardiac arrhythmias, considering the potential role of genetic predisposition and antiseizure medications (ASMs) in any associations observed.

METHODS

This population-based study evaluated UK Biobank data for individuals recruited between 2006 and 2010. Cox proportional hazards models and competing risk models were used to examine the association of epilepsy history with the long-term incidence risk of cardiac arrhythmias and arrhythmias subtypes. Polygenic risk scores (PRS) were calculated to investigate the effect of genetic susceptibility. The role of ASMs was also evaluated by integrating observational and drug target Mendelian randomization (MR) evidence.

RESULTS

The study included 329 432 individuals, including 2699 people with epilepsy. Compared with those without epilepsy, people with epilepsy experienced an increased risk of all cardiac arrhythmias [hazard ratio (HR) 1.36, 95% confidence interval (CI) 1.21-1.53], atrial fibrillation (HR 1.26, 95% CI 1.08-1.46), and other cardiac arrhythmias (HR 1.56, 95% CI 1.34-1.81). The associations were not modified by genetic predisposition as indicated by PRS. Competing and sensitivity analyses corroborated these results. Individuals with epilepsy using ASMs, especially carbamazepine and valproic acid, were at a higher risk for cardiac arrhythmias. This observation was further supported by drug target MR results (PSMR < .05 and PHEIDI > .05).

CONCLUSION

This study revealed the higher risk of cardiac arrhythmias persists long term in people with epilepsy, especially among those using carbamazepine and valproic acid. These findings highlight the need for regular heart rhythm monitoring and management in people with epilepsy in order to reduce the risk of further cardiovascular complications.

Copeptin: Up-to-date diagnostic and prognostic role highlight

Arginine Vasopressin (AVP) is one of the key hormones in the human body. AVP is clinically important because it maintains body fluid balance and vascular tone. Unfortunately, AVP laboratory measurements are always difficult and with low accuracy. Copeptin, the C-terminal of the AVP precursor, is released in equal amounts with AVP, making it a sensitive marker of AVP release. Despite being a non-specific biomarker, copeptin earned a lot of attention as a novel biomarker due to easy and quick laboratory measurements. Recent studies have reported the critical role of copeptin as a clinical indicator, especially in the diagnosis and prognosis of many diseases. Besides, it was reported that the combination between copeptin and gold standard biomarkers improved the prognostic values of those biomarkers. In this review, the role of copeptin as a new predictive diagnostic and prognostic biomarker of various diseases is highlighted according to the most recent studies. In addition, the importance of using copeptin as a marker in different medical departments and the impact of this on improving healthcare service was discussed.

Recurrent cerebellar ischemic infarctions and stereotyped peri-ictal sympathetic responses in a near-SUDEP patient with cardiovascular risk factors

We report a 60-year-old woman who presented to the emergency department after experiencing a witnessed unknown onset bilateral tonic clonic seizure (GTCS) that culminated in cardiac arrest. A neurology consultant uncovered a years-long history of frequent episodic staring followed by confusion and expressive aphasia, which strongly suggested that she suffered from epilepsy. Thus, her cardiac arrest and subsequent resuscitation met criteria for a near-sudden unexpected death in epilepsy (SUDEP) diagnosis. Serial bloodwork demonstrated transient troponin I elevations and leukocytoses, while a brain MRI revealed global cerebral anoxic injury and a small acute right cerebellar ischemic infarction. A review of her medical record uncovered a hospitalization sixteen months earlier for a likely GTCS whose workup showed similar troponin I elevations and leukocytoses, and surprisingly, a different small acute right cerebellar ischemic infarction in the same vascular territory. To our knowledge, this is the first report of subcortical ischemic infarctions occurring concurrently with GTCSs in a near-SUDEP patient. Aside from illustrating the key role of inpatient neurologists in the diagnosis of near-SUDEP, this manuscript discusses the potential significance of postictal ischemic infarctions, transient asymptomatic troponin elevations, and transient non-infectious leukocytoses in epilepsy patients with cardiovascular risk factors.

Measuring vagal activity in postictal bradycardia

Alterations to cardiac electrical conduction are some of the most frequently observed systemic complications of seizures, with autonomic dysregulation cited as the principal driver for these alterations. In this prospective study, we use 6-lead continuous ECG monitoring in hospitalized patients with epilepsy to trend heart rate patterns in the postictal period. A total of 117 seizures in 45 patients met the criteria for analysis. There was a postictal heart rate increase of 61% (n = 72 seizures), and a decline in heart rate (deceleration) following 38.5% (n = 45). Using 6-lead ECGs for waveform analysis revealed that there was PR prolongation accompanying those seizures that were associated with postictal bradycardia.

Cardiac structural and functional abnormalities in epilepsy: A systematic review and meta-analysis

OBJECTIVE

Epilepsy is associated with an increased risk of cardiovascular disease and mortality. Whether cardiac structure and function are altered in epilepsy remains unclear. To address this, we conducted a systematic review and meta-analysis of studies evaluating cardiac structure and function in patients with epilepsy.

METHODS

We searched the electronic databases MEDLINE, PubMed, COCHRANE, and Web of Science from inception to 31 December 2021. Primary outcomes of interest included left ventricular ejection fraction (LVEF) for studies reporting echocardiogram findings and cardiac weight and fibrosis for postmortem investigations. Study quality was assessed using the National Heart, Lung, and Blood Institute (NHLBI) assessment tools.

RESULTS

Among the 10 case-control studies with epilepsy patients (n = 515) and healthy controls (n = 445), LVEF was significantly decreased in epilepsy group compared with controls (MD: -1.80; 95% confidence interval [CI]: -3.56 to -0.04; P = 0.045), whereas A-wave velocity (MD: 4.73; 95% CI: 1.87-7.60; P = 0.001), E/e' ratio (MD: 0.39; 95% CI: 0.06-0.71; P = 0.019), and isovolumic relaxation time (MD: 10.18; 95% CI: 2.05-18.32; P = 0.014) were increased in epilepsy, compared with controls. A pooled analysis was performed in sudden unexpected death in epilepsy (SUDEP) cases with autopsy data (n = 714). Among SUDEP cases, the prevalence of cardiac hypertrophy was 16% (95% CI: 9%-23%); cardiac fibrosis was 20% (95% CI: 15%-26%). We found no marked differences in cardiac hypertrophy, heart weight, or cardiac fibrosis between SUDEP cases and epilepsy controls.

SIGNIFICANCE

Our findings suggest that epilepsy is associated with altered diastolic and systolic echocardiogram parameters compared with healthy controls. Notably, SUDEP does not appear to be associated with a higher incidence of structural cardiac abnormalities, compared with non-SUDEP epilepsy controls. Longitudinal studies are needed to understand the prognostic significance of such changes. Echocardiography may be a useful noninvasive diagnostic test in epilepsy population.

Review novel insights into the diagnostic and prognostic function of copeptin in daily clinical practice

As is shown in previous reports, arginine vasopressin (AVP), as one of the most important hormones within circulation in human beings, is of great clinically significance given that it could maintain the body fluid balance and vascular tone. However, the laboratory measurements AVP in daily clinical practice are shown to be difficult and with low accuracy. Concerning on this notion, it is unpractical to use the serum levels of AVP in diagnosing multiple diseases. On the other hand, another key serum biomarker, copeptin, is confirmed as the C-terminal of the AVP precursor which could be released in equal amounts with AVP, resultantly making it as a sensitive marker of arginine vasopressin release. Notably, emerging recent evidence has demonstrated the critical function of copeptin as a clinical indicator, especially in the diagnosis and prognosis of several diseases in diverse organs, such as cardiovascular disease, kidney disease, and pulmonary disease. In addition, copeptin was recently verified to play an important role in diagnosing multiple acute diseases when combined it with other gold standard serum biomarkers, indicating that copeptin could be recognized as a vital disease marker. Herein, in the current review, the functions of copeptin as a new predictive diagnostic and prognostic biomarker of various diseases, according to the most recent studies, are well summarized. Furthermore, the importance of using copeptin as a serum biomarker in diverse medical departments and the impact of this on improving healthcare service is also summarized in the current review.

Insular Role in Blood Pressure and Systemic Vascular Resistance Regulation

OBJECTIVES

The insula is a brain area involved in the modulation of autonomic responses. Previous studies have focused mainly on its heart rate regulatory function, but its role in vascular control is not well defined. Ictal/postictal blood pressure (BP) fluctuations may have a role in the pathogenesis of sudden unexpected death in epilepsy. This study aims to characterize the insular influence on vascular regulation through direct high-frequency electrical stimulation (E-stim) of different insular regions during stereo-electroencephalographic studies.

MATERIALS AND METHODS

An observational, prospective study was conducted, involving people with epilepsy who underwent E-stim of depth electrodes implanted in the insular cortex. Patients with anatomical or electrophysiological insular abnormalities, E-stim producing after discharges, or any elicited symptoms were excluded. Variations of BP and systemic vascular resistance (SVR) during the insular stimuli were analyzed, comparing them with those observed during E-stim of control contacts implanted in cortical noneloquent regions and sham stimulations.

RESULTS

Fourteen patients were included, five implanted in the right insula and nine in the left. We analyzed 14 stimulations in the right insula, 18 in the left insula, 18 in control electrodes, and 13 sham stimulations. Most right insular responses were hypertensive, whereas most left ones were hypotensive. E-stim of the right insula produced a significant BP and SVR increase, whereas the left insula induced a significant BP decrease without SVR changes. The most remarkable changes were elicited in both posterior insulas, although the magnitude of BP changes was generally low. Control and sham stimulations did not induce BP or SVR changes.

CONCLUSION

Our findings on insular stimulation suggest an interhemispheric difference in its vascular regulatory function, with a vasopressor effect of the right insula and a vasodilator effect of the left one.

Autonomic dysfunction in epilepsy mouse models with implications for SUDEP research

Epilepsy has a high prevalence and can severely impair quality of life and increase the risk of premature death. Sudden unexpected death in epilepsy (SUDEP) is the leading cause of death in drug-resistant epilepsy and most often results from respiratory and cardiac impairments due to brainstem dysfunction. Epileptic activity can spread widely, influencing neuronal activity in regions outside the epileptic network. The brainstem controls cardiorespiratory activity and arousal and reciprocally connects to cortical, diencephalic, and spinal cord areas. Epileptic activity can propagate trans-synaptically or via spreading depression (SD) to alter brainstem functions and cause cardiorespiratory dysfunction. The mechanisms by which seizures propagate to or otherwise impair brainstem function and trigger the cascading effects that cause SUDEP are poorly understood. We review insights from mouse models combined with new techniques to understand the pathophysiology of epilepsy and SUDEP. These techniques include in vivo, ex vivo, invasive and non-invasive methods in anesthetized and awake mice. Optogenetics combined with electrophysiological and optical manipulation and recording methods offer unique opportunities to study neuronal mechanisms under normal conditions, during and after non-fatal seizures, and in SUDEP. These combined approaches can advance our understanding of brainstem pathophysiology associated with seizures and SUDEP and may suggest strategies to prevent SUDEP.

Single-cell sequencing combined with machine learning reveals the mechanism of interaction between epilepsy and stress cardiomyopathy

Background

Epilepsy is a disorder that can manifest as abnormalities in neurological or physical function. Stress cardiomyopathy is closely associated with neurological stimulation. However, the mechanisms underlying the interrelationship between epilepsy and stress cardiomyopathy are unclear. This paper aims to explore the genetic features and potential molecular mechanisms shared in epilepsy and stress cardiomyopathy.

Methods

By analyzing the epilepsy dataset and stress cardiomyopathy dataset separately, the intersection of the two disease co-expressed differential genes is obtained, the co-expressed differential genes reveal the biological functions, the network is constructed, and the core modules are identified to reveal the interaction mechanism, the co-expressed genes with diagnostic validity are screened by machine learning algorithms, and the co-expressed genes are validated in parallel on the epilepsy single-cell data and the stress cardiomyopathy rat model.

Results

Epilepsy causes stress cardiomyopathy, and its key pathways are Complement and coagulation cascades, HIF-1 signaling pathway, its key co-expressed genes include SPOCK2, CTSZ, HLA-DMB, ALDOA, SFRP1, ERBB3. The key immune cell subpopulations localized by single-cell data are the T_cells subgroup, Microglia subgroup, Macrophage subgroup, Astrocyte subgroup, and Oligodendrocytes subgroup.

Conclusion

We believe epilepsy causing stress cardiomyopathy results from a multi-gene, multi-pathway combination. We identified the core co-expressed genes (SPOCK2, CTSZ, HLA-DMB, ALDOA, SFRP1, ERBB3) and the pathways that function in them (Complement and coagulation cascades, HIF-1 signaling pathway, JAK-STAT signaling pathway), and finally localized their key cellular subgroups (T_cells subgroup, Microglia subgroup, Macrophage subgroup, Astrocyte subgroup, and Oligodendrocytes subgroup). Also, combining cell subpopulations with hypercoagulability as well as sympathetic excitation further narrowed the cell subpopulations of related functions.

Dopamine, Immunity, and Disease

The neurotransmitter dopamine is a key factor in central nervous system (CNS) function, regulating many processes including reward, movement, and cognition. Dopamine also regulates critical functions in peripheral organs, such as blood pressure, renal activity, and intestinal motility. Beyond these functions, a growing body of evidence indicates that dopamine is an important immunoregulatory factor. Most types of immune cells express dopamine receptors and other dopaminergic proteins, and many immune cells take up, produce, store, and/or release dopamine, suggesting that dopaminergic immunomodulation is important for immune function. Targeting these pathways could be a promising avenue for the treatment of inflammation and disease, but despite increasing research in this area, data on the specific effects of dopamine on many immune cells and disease processes remain inconsistent and poorly understood. Therefore, this review integrates the current knowledge of the role of dopamine in immune cell function and inflammatory signaling across systems. We also discuss the current understanding of dopaminergic regulation of immune signaling in the CNS and peripheral tissues, highlighting the role of dopaminergic immunomodulation in diseases such as Parkinson's disease, several neuropsychiatric conditions, neurologic human immunodeficiency virus, inflammatory bowel disease, rheumatoid arthritis, and others. Careful consideration is given to the influence of experimental design on results, and we note a number of areas in need of further research. Overall, this review integrates our knowledge of dopaminergic immunology at the cellular, tissue, and disease level and prompts the development of therapeutics and strategies targeted toward ameliorating disease through dopaminergic regulation of immunity. SIGNIFICANCE STATEMENT: Canonically, dopamine is recognized as a neurotransmitter involved in the regulation of movement, cognition, and reward. However, dopamine also acts as an immune modulator in the central nervous system and periphery. This review comprehensively assesses the current knowledge of dopaminergic immunomodulation and the role of dopamine in disease pathogenesis at the cellular and tissue level. This will provide broad access to this information across fields, identify areas in need of further investigation, and drive the development of dopaminergic therapeutic strategies.

Epileptic seizures and Epilepsy Monitoring Unit admission disclose latent cardiac electrical instability

BACKGROUND

Sudden cardiac arrest results from cardiac electrical instability and is 3-fold more frequent in patients with chronic epilepsy than in the general population. We hypothesized that focal to bilateral tonic-clonic seizures (FTBTCS) would acutely impact T-wave alternans (TWA), a marker of cardiac electrical instability linked to an elevated risk for sudden cardiac death, more than focal seizures (FS) [focal aware seizures (FAS) and focal with impaired awareness seizures (FIAS)], due to their greater sympathetic stimulation of the heart. Since stress has been shown to cause significant TWA elevations in patients with heart disease, we also hypothesized that the early days of an inpatient admission to an epilepsy monitoring unit (EMU) would be associated with higher TWA levels compared to later hospital days in patients with chronic epilepsy, presumably due to stress.

DESIGN/METHODS

We analyzed the acute effects of seizures [FAS, FIAS, FTBTCS, and nonepileptic seizures (NES)] and day of hospital stay on TWA in 18 patients admitted to the EMU using high-resolution wireless electrocardiographic (ECG) patch monitors.

RESULTS

A total of 5 patients had FTBTCS, 7 patients had FS (2 FAS, 5 FIAS), and 3 patients had NES only during the index hospital stay. Four patients did not have any electroclinical seizures or NES. FTBTCS resulted in marked acute increases in ictal TWA from baseline (2 ± 0.3 µV) to ictal maximum (70 ± 6.1 µV, p < 0.0001), the latter exceeding the 60 µV cut point defined as severely abnormal. By comparison, while FAS and FIAS also provoked significant increases in TWA (from 2 ± 0.5 µV to 30 ± 3.3 µV, p < 0.0001), maximum ictal TWA levels did not reach the 47 µV cut point defined as abnormal. Heart rate increases during FTBTCS from baseline (62 ± 5.8 beats/min) to ictal maximum (134 ± 8.6 beats/min, an increase of 72 ± 7.2 beats/min, p < 0.02) were also greater (p = 0.014) than heart rate increases during FS (from 70 ± 5.2 beats/min to 118 ± 6.2 beats/min, an increase of 48 ± 2.6 beats/min, p < 0.03). In 3 patients with NES, TWA rose mildly during the patients' typical episodes (from 2 ± 0.6 µV to 14 ± 2.6 µV, p < 0.0004), well below the cut point of abnormality, while heart rate increases were observed (from 75 ± 1.3 to 112 ± 8.7 beats/min, an increase of 37 ± 8.9 beats/min, p = 0.03). Patients with EEG-confirmed electroclinical seizures recorded while in the EMU exhibited significantly elevated interictal TWA maxima (61 ± 3.4 µV) on EMU admission day which were similar in magnitude to ictal maxima seen during FTBTCS (70 ± 6.1 µV, p = 0.21). During subsequent days of hospitalization, daily interictal TWA maxima showed gradual habituation in patients with both FS and FTBTCS but not in patients with NES only.

CONCLUSIONS

This is the first study to our knowledge demonstrating that FTBTCS acutely provoke highly significant increases in TWA to levels that have been associated with heightened risk for sudden cardiac death in other patient populations. We speculate that mortality temporally associated with FTBTCS may, in some cases, be due to sudden cardiac death rather than respiratory failure. In patients with EEG-confirmed epilepsy, hospital admission is associated with interictal TWA maxima that approach those seen during FTBTCS, presumably related to stress during the early phase of hospitalization compared to later in the hospitalization, indicating cardiac electrical instability and potential vulnerability to sudden cardiac death related to stress independent of temporal relationships to seizures. The elevated heart rates observed acutely with seizures and on hospital Day 1 are consistent with a hyperadrenergic state and the effect of elevated sympathetic output on a vulnerable cardiac substrate, a phenomenon termed "the Epileptic Heart."

Protocols for multimodal polygraphy for cardiorespiratory monitoring in the epilepsy monitoring unit. Part II - Research acquisition

Multimodal polygraphy including cardiorespiratory monitoring is a valuable tool for epilepsy and sudden unexpected death in epilepsy (SUDEP) research. Broader applications in research into stress, anxiety, mood and other domains exist. Polygraphy techniques used during video electroencephalogram (EEG) recordings provide information on cardiac and respiratory changes in the peri-ictal period. In addition, such monitoring in brain mapping during chronic intracranial EEG evaluations has helped the understanding of pathomechanisms that lead to seizure induced cardiorespiratory dysfunction. Our aim here is to provide protocols and information on devices that may be used in the Epilepsy Monitoring Unit, in addition to proposed standard of care data acquisition. These devices include oronasal thermistors, oronasal pressure transducers, capnography, transcutaneous CO2 sensors, and continuous noninvasive blood pressure monitoring. Standard protocols for cardiorespiratory monitoring simultaneously with video EEG recording, may be useful in the study of cardiorespiratory phenomena in persons with epilepsy.

Impact of Cardiac Injury on the Clinical Outcome of Children with Convulsive Status Epilepticus

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.

Clinical correlates and prognostic impact of neurologic disorders in Takotsubo syndrome

Cardiac alterations are frequently observed after acute neurological disorders. Takotsubo syndrome (TTS) represents an acute heart failure syndrome and is increasingly recognized as part of the spectrum of cardiac complications observed after neurological disorders. A systematic investigation of TTS patients with neurological disorders has not been conducted yet. The aim of the study was to expand insights regarding neurological disease entities triggering TTS and to investigate the clinical profile and outcomes of TTS patients after primary neurological disorders. The International Takotsubo Registry is an observational multicenter collaborative effort of 45 centers in 14 countries (ClinicalTrials.gov, identifier NCT01947621). All patients in the registry fulfilled International Takotsubo Diagnostic Criteria. For the present study, patients were included if complete information on acute neurological disorders were available. 2402 patients in whom complete information on acute neurological status were available were analyzed. In 161 patients (6.7%) an acute neurological disorder was identified as the preceding triggering factor. The most common neurological disorders were seizures, intracranial hemorrhage, and ischemic stroke. Time from neurological symptoms to TTS diagnosis was ≤ 2 days in 87.3% of cases. TTS patients with neurological disorders were younger, had a lower female predominance, fewer cardiac symptoms, lower left ventricular ejection fraction, and higher levels of cardiac biomarkers. TTS patients with neurological disorders had a 3.2-fold increased odds of in-hospital mortality compared to TTS patients without neurological disorders. In this large-scale study, 1 out of 15 TTS patients had an acute neurological condition as the underlying triggering factor. Our data emphasize that a wide spectrum of neurological diseases ranging from benign to life-threatening encompass TTS. The high rates of adverse events highlight the need for clinical awareness.

Autonomic manifestations of epilepsy: emerging pathways to sudden death?

Epileptic networks are intimately connected with the autonomic nervous system, as exemplified by a plethora of ictal (during a seizure) autonomic manifestations, including epigastric sensations, palpitations, goosebumps and syncope (fainting). Ictal autonomic changes might serve as diagnostic clues, provide targets for seizure detection and help us to understand the mechanisms that underlie sudden unexpected death in epilepsy (SUDEP). Autonomic alterations are generally more prominent in focal seizures originating from the temporal lobe, demonstrating the importance of limbic structures to the autonomic nervous system, and are particularly pronounced in focal-to-bilateral and generalized tonic-clonic seizures. The presence, type and severity of autonomic features are determined by the seizure onset zone, propagation pathways, lateralization and timing of the seizures, and the presence of interictal autonomic dysfunction. Evidence is mounting that not all autonomic manifestations are linked to SUDEP. In addition, experimental and clinical data emphasize the heterogeneity of SUDEP and its infrequent overlap with sudden cardiac death. Here, we review the spectrum and diagnostic value of the mostly benign and self-limiting autonomic manifestations of epilepsy. In particular, we focus on presentations that are likely to contribute to SUDEP and discuss how wearable devices might help to prevent SUDEP.

Heart rate variability in patients with refractory epilepsy: The influence of generalized convulsive seizures

OBJECTIVE

Patients with epilepsy, mainly drug-resistant, have reduced heart rate variability (HRV), linked to an increased risk of sudden death in various other diseases. In this context, it could play a role in SUDEP. Generalized convulsive seizures (GCS) are one of the most consensual risk factors for SUDEP. Our objective was to assess the influence of GCS in HRV parameters in patients with drug-resistant epilepsy.

METHODS

We prospectively evaluated 121 patients with refractory epilepsy admitted to our Epilepsy Monitoring Unit. All patients underwent a 48-hour Holter recording. Only patients with GCS were included (n = 23), and we selected the first as the index seizure. We evaluated HRV (AVNN, SDNN, RMSSD, pNN50, LF, HF, and LF/HF) in 5-min epochs (diurnal and nocturnal baselines; preictal - 5 min before the seizure; ictal; postictal - 5 min after the seizure; and late postictal - >5 h after the seizure). These data were also compared with normative values from a healthy population (controlling for age and gender).

RESULTS

We included 23 patients, with a median age of 36 (min-max, 16-55) years and 65% were female. Thirty percent had cardiovascular risk factors, but no previously known cardiac disease. HRV parameters AVNN, RMSSD, pNN50, and HF were significantly lower in the diurnal than in the nocturnal baseline, whereas the opposite occurred with LF/HF and HR. Diurnal baseline parameters were inferior to the normative population values (which includes only diurnal values). We found significant differences in HRV parameters between the analyzed periods, especially during the postictal period. All parameters but LF/HF suffered a reduction in that period. LF/HF increased in that period but did not reach statistical significance. Visually, there was a tendency for a global reduction in our patients' HRV parameters, namely AVNN, RMSSD, and pNN50, in each period, comparing with those from a normative healthy population. No significant differences were found in HRV between diurnal and nocturnal seizures, between temporal lobe and extra-temporal-lobe seizures, between seizures with and without postictal generalized EEG suppression, or between seizures of patients with and without cardiovascular risk factors.

SIGNIFICANCE/CONCLUSION

Our work reinforces the evidence of autonomic cardiac dysfunction in patients with refractory epilepsy, at baseline and mainly in the postictal phase of a GCS. Those changes may have a role in some SUDEP cases. By identifying patients with worse autonomic cardiac function, HRV could fill the gap of a lacking SUDEP risk biomarker.

Biomarkers Utility: At the Borderline between Cardiology and Neurology

Biomarkers are important diagnostic and prognostic tools as they provide results in a short time while still being an inexpensive, reproducible and accessible method. Their well-known benefits have placed them at the forefront of research in recent years, with new and innovative discoveries being implemented. Cardiovascular and neurological diseases often share common risk factors and pathological pathways which may play an important role in the use and interpretation of biomarkers' values. Among the biomarkers used extensively in clinical practice in cardiology, hs-TroponinT, CK-MB and NTproBNP have been shown to be strongly influenced by multiple neurological conditions. Newer ones such as galectin-3, lysophosphatidylcholine, copeptin, sST2, S100B, myeloperoxidase and GDF-15 have been extensively studied in recent years as alternatives with an increased sensitivity for cardiovascular diseases, but also with significant results in the field of neurology. Thus, given their low specificity, the values interpretation must be correlated with the clinical judgment and other available investigations.

Copeptin and Stress

Vasopressin (AVP) and copeptin are released in equimolar amounts from the same precursor. Due to its molecular stability and countless advantages as compared with AVP, copeptin perfectly mirrors AVP presence and has progressively emerged as a reliable marker of vasopressinergic activation in response to osmotic and hemodynamic stimuli in clinical practice. Moreover, evidence highlighting the prognostic potential of copeptin in several acute diseases, where the activation of the AVP system is primarily linked to stress, as well as in psychologically stressful conditions, has progressively emerged. Furthermore, organic stressors induce a rise in copeptin levels which, although non-specific, is unrelated to plasma osmolality but proportional to their magnitude: suggesting disease severity, copeptin proved to be a reliable prognostic biomarker in acute conditions, such as sepsis, early post-surgical period, cardiovascular, cerebrovascular or pulmonary diseases, and even in critical settings. Evidence on this topic will be briefly discussed in this article.

Epileptic heart: A clinical syndromic approach

Prevention of premature death in patients with chronic epilepsy remains a major challenge. Multiple pathophysiologic factors have been implicated, with intense investigation of cardiorespiratory mechanisms. Up to four in five patients with chronic epilepsy exhibit cardiovascular comorbidities. These findings led us to propose the concept of an "epileptic heart," defined as "a heart and coronary vasculature damaged by chronic epilepsy as a result of repeated surges in catecholamines and hypoxemia leading to electrical and mechanical dysfunction." Among the most prominent changes documented in the literature are high incidence of myocardial infarction and arrhythmia, altered autonomic tone, diastolic dysfunction, hyperlipidemia, and accelerated atherosclerosis. This suite of pathologic changes prompted us to propose for the first time in this review a syndromic approach for improved clinical detection of the epileptic heart condition. In this review, we discuss the key pathophysiologic mechanisms underlying the candidate criteria along with standard and novel techniques that permit evaluation of each of these factors. Specifically, we present evidence of the utility of standard 12-lead, ambulatory, and multiday patch-based electrocardiograms, along with measures of cardiac electrical instability, including T-wave alternans, heart rate variability to detect altered autonomic tone, echocardiography to detect diastolic dysfunction, and plasma biomarkers for assessing hyperlipidemia and accelerated atherosclerosis. Ultimately, the proposed clinical syndromic approach is intended to improve monitoring and evaluation of cardiac risk in patients with chronic epilepsy to foster improved therapeutic strategies to reduce premature cardiac death.

Seizures and status epilepticus may be risk factor for cardiac arrhythmia or cardiac arrest across multiple time frames

OBJECTIVE

To determine if Emergency Department (ED) or inpatient encounters for epilepsy or status epilepticus are associated with increased odds of cardiac arrhythmia or cardiac arrest over successively longer time frames.

METHODS

The State Inpatient and ED Databases (from New York, Florida, and California) are statewide datasets containing data on 97% of hospitalizations and ED encounters from these states. In this retrospective, case-crossover study, we used International Classification of Diseases, Ninth Revision, Clinical Modification codes to identify index cardiac arrhythmia encounters. Exposures were inpatient or ED encounters for epilepsy or status epilepticus. The case-crossover analysis tested whether an epilepsy or status epilepticus encounter within various case periods (1, 3, 7, 30, 60, 90, and 180 days prior to index encounter) was associated with subsequent ED or inpatient encounter for cardiac arrhythmia, as compared to control periods of equal length one year prior.

RESULTS

The odds ratio (OR) for cardiac arrhythmia after an epilepsy encounter was significant at all time intervals (OR range 2.37-3.36), and highest at 1 day after epilepsy encounter (OR 3.63, 95% confidence interval [CI] 1.66-7.93, p = 0.0013). The OR after status epilepticus was significant at 7- to 180-day intervals (OR range 2.25-2.74), and highest at 60 days (OR 2.74, CI 2.09-3.61, p < 0.0001).

SIGNIFICANCE

Epilepsy and status epilepticus events are associated with increased odds of subsequent cardiac arrhythmia or cardiac arrest over multiple chronic timeframes. Increased cardiac surveillance may be warranted to minimize morbidity and mortality in patients with epilepsy.

Ictal and Interictal Cardiac Manifestations in Epilepsy. A Review of Their Relation With an Altered Central Control of Autonomic Functions and With the Risk of SUDEP

There is a complex interrelation between epilepsy and cardiac pathology, with both acute and long-term effects of seizures on the regulation of the cardiac rhythm and on the heart functioning. A specific issue is the potential relation between these cardiac manifestations and the risk of Sudden and Unexpected Death in Epilepsy (SUDEP), with unclear respective role of centrally-control ictal changes, long-term epilepsy-related dysregulation of the neurovegetative control and direct effects on the heart function. In the present review, we detailed available data about ictal cardiac changes, along with interictal cardiac manifestations associated with long-term functional and structural alterations of the heart. Pathophysiological mechanisms of these cardiac changes are discussed, with a specific focus on central mechanisms and the investigation of a possible deregulation of the central control of autonomic functions in addition to the role of catecholamine and hypoxemia on heart.

Serotonin and dopamine receptors profile on peripheral immune cells from patients with temporal lobe epilepsy

The role of inflammation and immune cells has been demonstrated in neurological diseases, including epilepsy. Leukocytes, as well as inflammatory mediators, contribute to abnormal processes that lead to a reduction in seizure threshold and synaptic reorganization. In this sense, identifying different phenotypes of circulating immune cells is essential to understanding the role of these cells in epilepsy. Immune cells can express a variety of surface markers, including neurotransmitter receptors, such as serotonin and dopamine. Alteration in these receptors expression patterns may affect the level of inflammatory mediators and the pathophysiology of epilepsy. Therefore, in the current study, we evaluated the expression of dopamine and serotonin receptors on white blood cells from patients with temporal lobe epilepsy with hippocampal sclerosis (TLE-HS). Blood samples from 17 patients with TLE-HS and 21 controls were collected. PBMC were isolated and stained ex vivo for flow cytometry. We evaluated the expression of serotonin (5-HT_1A, 5-HT_1B, 5-HT₂, 5-HT_2B, 5-HT_2C, 5-HT₃, 5-HT₄), and dopamine receptors (D₁, D₂, D₃, D₄, and D₅) on the cell surface of lymphocytes and innate immune cells (monocytes and granulocytes). Our results demonstrated that innate cells and lymphocytes from patients with TLE-HS showed high mean fluorescent intensity (MFI) for 5-HT_1A, 5-HT_1B, 5-HT_2A, and 5-HT₄ compared to controls. No difference was observed for 5-HT_2B. For dopamine receptors, the expression of D₁, D₂, D_4, and D₅ receptors was higher on innate cells from patients with TLE-HS when compared to controls for the MFI. Regarding lymphocytes population, D₂ expression was increased in patients with TLE-HS. In conclusion, there are alterations in the expression of serotonin and dopamine receptors on immune blood cells of patients with TLE-HS. Although the biological significance of these findings still needs to be further investigated, these changes may contribute to the understanding of TLE-HS pathophysiology.

The evaluation of pituitary damage associated with cardiac arrest: An experimental rodent model

The pituitary gland plays an important endocrinal role, however its damage after cardiac arrest (CA) has not been well elucidated. The aim of this study was to determine a pituitary gland damage induced by CA. Rats were subjected to 10-min asphyxia and cardiopulmonary resuscitation (CPR). Immunohistochemistry and ELISA assays were used to evaluate the pituitary damage and endocrine function. Samples were collected at pre-CA, and 30 and 120 min after cardio pulmonary resuscitation. Triphenyltetrazolium chloride (TTC) staining demonstrated the expansion of the pituitary damage over time. There was phenotypic validity between the pars distalis and nervosa. Both CT-proAVP (pars nervosa hormone) and GH/IGF-1 (pars distalis hormone) decreased over time, and a different expression pattern corresponding to the damaged areas was noted (CT-proAVP, 30.2 ± 6.2, 31.5 ± 5.9, and 16.3 ± 7.6 pg/mg protein, p < 0.01; GH/IGF-1, 2.63 ± 0.61, 0.62 ± 0.36, and 2.01 ± 0.41 ng/mg protein, p < 0.01 respectively). Similarly, the expression pattern between these hormones in the end-organ systems showed phenotypic validity. Plasma CT-proAVP (r = 0.771, p = 0.025) and IGF-1 (r = −0.775, p = 0.024) demonstrated a strong correlation with TTC staining area. Our data suggested that CA induces pathological and functional damage to the pituitary gland.

Left ventricle end-systolic elastance, arterial-effective elastance, and ventricle-arterial coupling in Epilepsy

OBJECTIVE

Sudden unexpected death in epilepsy (SUDEP) is a tragic event. Cardiac models of sudden death state that, paradoxically, healthy individuals compose most of the victims of this event. Exploration of cardiac physiological variables related to outcome could help unveil risk markers for sudden death in epilepsy. We investigated left ventricle end-systolic elastance, arterial-effective elastance and ventricle-arterial coupling (VAC) in PWE compared with controls.

MATERIAL & METHODS

Adult patients with temporal lobe epilepsy without known cardiovascular diseases were submitted to treadmill test and transthoracic echocardiogram. Individuals without epilepsy matched by sex, age, and body mass index composed the control group. Cardiac risk factors, exercise performance, autonomic data from treadmill test, systolic and diastolic function, morphological cardiac data, and left ventricle pressure-volume loop were recorded.

RESULTS

Sixty subjects were consecutively enrolled (30 PWE and 30 controls). Epilepsy duration was 22.5 ± 10.7 years (age of onset 15.2 ± 10.1 years). Treadmill variables were significantly worse in TLE patients compared with controls. End-systolic elastance, arterial-effective elastance, and ventricle-arterial coupling were similar between groups. Female sex, percentage of maximal predicted heart rate achieved in exercise, exercise time, and epilepsy duration explained 28,4% of VAC in PWE in multiple stepwise linear regression (P = .018).

CONCLUSIONS

Some aspects of the cardiac pressure-volume curves, mainly linked to left ventricle systolic performance, contractile function and their interaction with afterload appears normal in young PWE and cannot explain their increase risk to adverse outcomes or lower physical fitness.

Neurological update: use of cardiac troponin in patients with stroke

Cardiac troponin is a specific and sensitive biomarker to identify and quantify myocardial injury. Myocardial injury is frequently detected after acute ischemic stroke and strongly associated with unfavorable outcomes. Concomitant acute coronary syndrome is only one of several possible differential diagnoses that may cause elevation of cardiac troponin after stroke. As a result, there are uncertainties regarding the correct interpretation and optimal management of stroke patients with myocardial injury in clinical practice. Elevation of cardiac troponin may occur as part of a 'Stroke-Heart Syndrome'. The term 'Stroke-Heart Syndrome' subsumes a clinical spectrum of cardiac complications after stroke including cardiac injury, dysfunction, and arrhythmia which may relate to disturbances of autonomic function and the brain-heart axis. In this review, we provide an up-to-date overview about prognostic implications, mechanisms, and management of elevated cardiac troponin levels in patients with acute ischemic stroke.

Serum biomarkers of cerebral cellular stress after self-limiting tonic clonic seizures: An exploratory study

OBJECTIVE

It has been debated for decades whether single, self-limited seizures damage cerebral cells. Meanwhile, very sensitive measurements of biomarkers have become available, i.e. tau, neurofilament protein light (NFL), glial fibrillary acidic protein (GFAP) and ubiquitin carboxyterminate hydrolase L1 (UCHL-1), which we explored in this study.

METHODS

Adult patients of the epilepsy monitoring unit were admitted to the study after written consent. Blood samples were drawn at baseline, immediately after a TCS and after two, six and 24 h. The markers were measured from frozen samples with a single-molecule array (SIMOA).

RESULTS

20 patients and 20 seizures were included. All markers showed subtle but significant postictal increases and returned to normal within the next few hours (p < 0.05). An increase of at least 100 % from baseline was noted in 30 % of patients for tau, 25 % for UCHL-1 and 15 % for GFAP, while NFL levels never increased above 100 %. Lactate was slightly correlated with the tau increase (r = 0.47, p = 0.037), leukocytes were correlated with postictal changes of GFAP (r = 0.68 p = 0.001).

CONCLUSION

Our data supports the assumption that significant cerebral stress occurs in some but not all self-limited TCS. The postictal inflammatory response in particular seems to play an important role.

Association of Peri-ictal Brainstem Posturing With Seizure Severity and Breathing Compromise in Patients With Generalized Convulsive Seizures

OBJECTIVE

To analyze the association between peri-ictal brainstem posturing semiologies with postictal generalized electroencephalographic suppression (PGES) and breathing dysfunction in generalized convulsive seizures (GCS).

METHODS

In this prospective, multicenter analysis of GCS, ictal brainstem semiology was classified as (1) decerebration (bilateral symmetric tonic arm extension), (2) decortication (bilateral symmetric tonic arm flexion only), (3) hemi-decerebration (unilateral tonic arm extension with contralateral flexion) and (4) absence of ictal tonic phase. Postictal posturing was also assessed. Respiration was monitored with thoracoabdominal belts, video, and pulse oximetry.

RESULTS

Two hundred ninety-five seizures (180 patients) were analyzed. Ictal decerebration was observed in 122 of 295 (41.4%), decortication in 47 of 295 (15.9%), and hemi-decerebration in 28 of 295 (9.5%) seizures. Tonic phase was absent in 98 of 295 (33.2%) seizures. Postictal posturing occurred in 18 of 295 (6.1%) seizures. PGES risk increased with ictal decerebration (odds ratio [OR] 14.79, 95% confidence interval [CI] 6.18-35.39, p < 0.001), decortication (OR 11.26, 95% CI 2.96-42.93, p < 0.001), or hemi-decerebration (OR 48.56, 95% CI 6.07-388.78, p < 0.001). Ictal decerebration was associated with longer PGES (p = 0.011). Postictal posturing was associated with postconvulsive central apnea (PCCA) (p = 0.004), longer hypoxemia (p < 0.001), and Spo₂ recovery (p = 0.035).

CONCLUSIONS

Ictal brainstem semiology is associated with increased PGES risk. Ictal decerebration is associated with longer PGES. Postictal posturing is associated with a 6-fold increased risk of PCCA, longer hypoxemia, and Spo₂ recovery. Peri-ictal brainstem posturing may be a surrogate biomarker for GCS severity identifiable without in-hospital monitoring.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that peri-ictal brainstem posturing is associated with the GCS with more prolonged PGES and more severe breathing dysfunction.

Directed Connectivity Analysis of the Neuro-Cardio- and Respiratory Systems Reveals Novel Biomarkers of Susceptibility to SUDEP

Sudden unexpected death in epilepsy (SUDEP) is the leading cause of epilepsy-related mortality and its pathophysiological mechanisms remain unknown. Goal: We set to record and analyze for the first time concurrent electroencephalographic (EEG), electrocardiographic (ECG), and unrestrained whole-body plethysmographic (Pleth) signals from control (WT - wild type) and SUDEP-prone mice (KO- knockout Kcna1 animal model). Methods: Employing multivariate autoregressive models (MVAR) we measured all tri-organ effective directional interactions by the generalized partial directed coherence (GPDC) in the frequency domain over time (hours). Results: When compared to the control (WT) animals, the SUDEP-prone (KO) animals exhibited (p < 0.001) reduced afferent and efferent interactions between the heart and the brain over the full frequency spectrum (0-200Hz), enhanced efferent interactions from the brain to the lungs and from the heart to the lungs at high (>90 Hz) frequencies (especially during periods with seizure activity), and decreased feedback from the lungs to the brain at low (<40 Hz) frequencies. Conclusions: These results show that impairment in the afferent and efferent pathways in the holistic neuro-cardio-respiratory network could lead to SUDEP, and effective connectivity measures and their dynamics could serve as novel biomarkers of susceptibility to SUDEP and seizures respectively.

cTnI, BNP and CRP profiling after seizures in patients with drug-resistant epilepsy

PURPOSE

To profile serum levels of high sensitivity Troponin I (hs-cTnI), B-Type Natriuretic Peptide (BNP), and high sensitivity C Reactive Protein (hs-CRP), after epileptic seizures in patients with focal drug-resistant epilepsy, relating the results to the revised SUDEP-7 inventory.

METHODS

We prospectively evaluated patients admitted to our Epilepsy Monitoring Unit. hs-cTnI, BNP, and hs-CRP were measured at admission and after the first seizure. The revised SUDEP-7 Risk Inventory was calculated. The statistical significance level was set at 0.05.

RESULTS

Fifty-eight patients were included (53.4 % female). The index seizure was a focal to bilateral tonic-clonic seizure (FBTCS) in 25.9 % of the patients, and 17.5 % had post-ictal generalized EEG suppression (PGES). After the seizure, 25.9 % had a significant (above 50 %) increase in hs-cTnI, 23.3 % in BNP, and 4.3 % in hs-CRP. About 40 % had cardiovascular risk factors (CRF), without known cardiac disease. The elevation of one biomarker did not compel the elevation of another. hs-cTnI increase was associated with FBTCS, PGES, longer seizures, maximal ictal heart rate, and HR change. Increases in BNP were associated with CRF. hs-CRP increase was associated with PGES. We found no significant association between SUDEP-7 and any biomarker increase.

SIGNIFICANCE

Several patients had increases in biomarkers of myocardial necrosis/dysfunction after seizures, without significant association with the SUDEP-7 inventory. Different patterns of biomarkers' elevations point to multifactorial pathophysiologies hypothetically associated with incipient myocardial lesions. A larger cohort with follow-up data could help to clarify the clinical relevance of these findings.

Prevention of sudden unexpected death in epilepsy: current status and future perspectives

Introduction: Sudden unexpected death in epilepsy (SUDEP) affects about 1 in 1000 people with epilepsy, and even more in medically refractory epilepsy. As most people are between 20 and 40 years when dying suddenly, SUDEP leads to a considerable loss of potential life years. The most important risk factors are nocturnal and tonic-clonic seizures, underscoring that supervision and effective seizure control are key elements for SUDEP prevention. The question of whether specific antiepileptic drugs are linked to SUDEP is still controversially discussed. Knowledge and education about SUDEP among health-care professionals, patients, and relatives are of outstanding importance for preventive measures to be taken, but still poor and widely neglected.Areas covered: This article reviews epidemiology, pathophysiology, risk factors, assessment of individual SUDEP risk and available measures for SUDEP prevention. Literature search was done using Medline and Pubmed in October 2019.Expert opinion: Significant advances in the understanding of SUDEP were made in the last decade which allow testing of novel strategies to prevent SUDEP. Promising current strategies target neuronal mechanisms of brain stem dysfunction, cardiac susceptibility for fatal arrhythmias, and reliable detection of tonic-clonic seizures using mobile health technologies.Abbreviations: AED, antiepileptic drug; CBZ, carbamazepine; cLQTS, congenital long QT syndrome; EMU, epilepsy monitoring unit; FBTCS, focal to bilateral tonic-clonic seizures; GTCS, generalized tonic-clonic seizures; ICA, ictal central apnea; LTG, lamotrigine; PCCA, postconvulsive central apnea; PGES, postictal generalized EEG suppression; SRI, serotonin reuptake inhibitor; SUDEP, sudden unexpected death in epilepsy; TCS, tonic-clonic seizures.

The Epileptic Heart: Concept and clinical evidence

Sudden unexpected death in epilepsy (SUDEP) is generally considered to result from a seizure, typically convulsive and usually but not always occurring during sleep, followed by a sequence of events in the postictal period starting with respiratory distress and progressing to eventual cardiac asystole and death. Yet, recent community-based studies indicate a 3-fold greater incidence of sudden cardiac death in patients with chronic epilepsy than in the general population, and that in 66% of cases, the cardiac arrest occurred during routine daily activity and without a temporal relationship with a typical seizure. To distinguish a primarily cardiac cause of death in patients with epilepsy from the above description of SUDEP, we propose the concept of the "Epileptic Heart" as "a heart and coronary vasculature damaged by chronic epilepsy as a result of repeated surges in catecholamines and hypoxemia leading to electrical and mechanical dysfunction." This review starts with an overview of the pathophysiological and other lines of evidence supporting the biological plausibility of the Epileptic Heart, followed by a description of tools that have been used to generate new electrocardiogram (EKG)-derived data in patients with epilepsy that strongly support the Epileptic Heart concept and its propensity to cause sudden cardiac death in patients with epilepsy independent of an immediately preceding seizure.

Time courses of HMGB1 and other inflammatory markers after generalized convulsive seizures

PURPOSE

Neuroinflammation and disruption of blood brain barrier (BBB) are important players in epileptogenesis, ictogenesis and pharmacoresistance. In this context, we investigated blood levels of HMGB1 and other inflammatory and BBB markers after generalized and focal to bilateral tonic-clonic seizures in serum, summarized under the term generalized convulsive seizures (GCS).

METHODS

We included consenting adults who were admitted to the epilepsy monitoring unit. Blood samples were drawn at baseline and immediately after a GCS as well as after 2, 6 and 24 h. We measured leukocytes, c-reactive protein (CRP), the danger-associated molecular patterns (DAMPs) high mobility group box 1 (HMGB1) and S100, receptor of advanced glycation end products (RAGE) alongside the BBB markers intercellular adhesion molecule-1 (ICAM1) and matrix metalloproteinase 9 (MMP9). Noradrenaline and lactate measurements were available from a previous study. P-levels <0.05 were regarded as significant.

RESULTS

Twenty-eight patients with 28 GCS were included. Leukocytosis occurred immediately after GCS and normalized within two hours (p < 0.001). S100 and HMGB1 both increased by ∼80 % (p < 0.001). MMP9 peaked after six hours with levels at 48.6 % above baseline. RAGE decreased by 17.6 % with a nadir at 24 h. CRP increased by 118 % with a peak at 24 h. ICAM1 remained stable (p = 0.068). Postictal HMGB1 correlated with postictal leukocytosis (r = 0.42; p = 0.025) and with MMP9 levels six hours later (r = 0.374; p = 0.05). Postictal lactate levels correlated with MMP9 at 6 h (r = 0.48; p = 0.01) and CRP at 24 h (r = 0.39; p = 0.04). Postictal noradrenaline correlated with lactate (r = 0.57; p = 0.02) and leukocytes (r = 0.39; p = 0.047).

DISCUSSION

The serum level of the DAMPs HMGB1 and S100 increase immediately after GCS. The hypothetical mechanism includes central nervous processes, such as glutamate toxicity and ROS release from seizing neurons but also muscular tissues. BBB breakdown is marked by the release of MMP9. Further research is needed to understand the complex interactions between electrical and metabolic stress, neuroinflammation and BBB mechanics in seizures and epilepsy.

CONCLUSION

Our study reveals signs of inflammation, neuronal damage and transitory disruption of BBB following single GCS, underscoring the widespread and possibily detrimental effects of recurrent seizures on brain properties. The long term impact on the disease course, however, is unclear.

Acute metabolic effects of tonic-clonic seizures

OBJECTIVE

Tonic-clonic seizures (TCS) lead to metabolic stress and changes in related blood markers. Such markers may indicate harmful conditions but can also help to identify TCS as a cause of transient loss of consciousness. In this study, we hypothesized that the alterations of circulating markers of metabolic stress depend on the clinical features of TCS.

METHODS

Ninety-one adults undergoing video-EEG monitoring participated in this prospective study. Electrolytes, renal parameters, creatine kinase (CK), prolactin (PRL), lactate, ammonia, glucose, and other parameters were measured at inclusion and different time points after TCS.

RESULTS

A total of 39 TCS were recorded in 32 patients (six generalized onset tonic-clonic seizures in 6 and 33 focal to bilateral tonic-clonic seizures in 26 patients). Shortly after TCS, mean lactate, ammonia, and PRL levels were significantly increased 8.7-fold, 2.6-fold, and 5.1-fold, respectively, with levels of more than twofold above the upper limits of the normal (ULN) in 90%, 71%, and 70% of the TCS and returned to baseline levels within 2 hours. Only postictal lactate levels were significantly correlated with the total duration of the tonic-clonic phase. In contrast, CK elevations above the ULN were found in three TCS (~10%) only with a peak after 48 hours. Immediately after the TCS, hyperphosphatemia occurred in one third of the patients, whereas hypophosphatemia was observed in one third 2 hours later. TCS led to subtle but significant alterations of other electrolytes, creatinine, and uric acid, whereas glucose levels were moderately increased.

SIGNIFICANCE

Lactate is a robust metabolic marker of TCS with elevations found in ~90% of cases within 30 minutes after seizure termination, whereas ammonia rises in ~ 70%, similarly to PRL. Phosphate levels show an early increase and a decrease 2 hours after TCS in a third of patients. CK elevations are rare after video-EEG-documented TCS, challenging its value as a diagnostic marker.

Cardiac stress after electroconvulsive therapy and spontaneous generalized convulsive seizures: A prospective echocardiographic and blood biomarker study

AIM

Knowledge about cardiac stress related to seizures in electroconvulsive therapy (ECT) and spontaneously occurring generalized convulsive seizures (GCS) is limited. The aim of the present study was to analyze cardiac function and circulating markers of cardiac stress in the early postictal period after ECT and GCS.

METHODS

Patients undergoing ECT in the Department of Psychiatry, Psychotherapy and Psychosomatics and patients undergoing diagnostic video-EEG monitoring (VEM) in the Department of Neurology were prospectively enrolled between November 2017 and November 2018. Cardiac function was examined twice using transthoracic echocardiography within 60 min and >4 h after ECT or GCS. Established blood markers (troponin T high-sensitive, N-terminal pro brain natriuretic peptide) of cardiac stress or injury were collected within 30 min, 4 to 6 h, and 24 h after ECT or GCS. In the ECT group, the troponin T values were also correlated with periprocedural heart rate and blood pressure values. Because of organizational or technical reasons, the measurement was not performed in all patients.

RESULTS

Twenty patients undergoing ECT and 6 patients with epilepsy with a GCS during VEM were included. Postictal echocardiography showed no wall motion disorders and no change in left ventricular and right ventricular functions. Four of 17 patients displayed a transient increase in high-sensitive cardiac troponin T 4-6 h after the seizure (3 patients with ECT-induced seizure). None of these 4 patients had signs of an acute cardiac event, and periprocedural blood pressure or heart rate peaks during ECT did not significantly differ in patients with and without troponin T elevation.

CONCLUSIONS

Signs of mild cardiac stress can occur in some patients following ECT or GCS without clinical complications, probably related to excessive catecholamine release during the seizure.

Epilepsy and ultra-structural heart changes: The role of catecholaminergic toxicity and myocardial fibrosis. What can we learn from cardiology?

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.

Repeated generalized seizures can produce calcified cardiac lesions in DBA/1 mice

Studies suggest that cardiorespiratory dysfunction likely contributes to sudden unexpected death in epilepsy (SUDEP). Seizures result in autonomic and respiratory dysfunction, leading to sympathetic hyperactivity and respiratory distress, including apnea. While the heart is vulnerable to catecholamine surges and hypoxia, it remains unknown if repetitive generalized seizures lead to cardiac damage. DBA/1 mice exhibit seizure-induced respiratory arrest (S-IRA) following generalized audiogenic seizures (AGS), which can be resuscitated using a rodent ventilator. In the current study, we induced different numbers of S-IRA episodes in DBA/1 mice and determined the association of repeated S-IRA induction with cardiac damage using histology. After repetitive induction of 18 S-IRA, calcified lesions, as revealed by calcium (Ca²⁺)-specific alizarin red staining, were observed in the ventricular myocardium in 61.5% of DBA/1 mice, which was higher compared to mice with 5 S-IRA and 1 S-IRA as well as age-matched untested control mice. The incidence of lesions in mice with 9 S-IRA was only higher than that of control mice. Only 1-2, small lesions were observed in mice with 5 S-IRA and 1 S-IRA and in control mice. Larger lesions (>2500 μm²) were observed in mice with 9 and 18 S-IRA. The incidence of larger lesions was higher in mice with 18 S-IRA (53.8%) as compared to mice with 5 S-IRA and 1 S-IRA as well as with control mice, and the incidence of larger lesions in mice with 9 S-IRA was only higher than that of control mice. Repeated induction of S-IRA in DBA/1 mice can result in calcified necrotic lesions in the ventricles of the heart, and their incidence and size are dependent on the total number of S-IRA.

Blood Pressure in Seizures and Epilepsy

In this narrative review, we summarize the current knowledge of neurally mediated blood pressure (BP) control and discuss how recently described epilepsy- and seizure-related BP alterations may contribute to premature mortality and sudden unexpected death in epilepsy (SUDEP). Although people with epilepsy display disturbed interictal autonomic function with a shift toward predominant sympathetic activity, prevalence of arterial hypertension is similar in people with and without epilepsy. BP is transiently increased in association with most types of epileptic seizures but may also decrease in some, illustrating that seizure activity can cause both a decrease and increase of BP, probably because of stimulation or inhibition of distinct central autonomic function by epileptic activity that propagates into different neuronal networks of the central autonomic nervous system. The principal regulatory neural loop for short-term BP control is termed baroreflex, mainly involving peripheral sensors and brain stem nuclei. The baroreflex sensitivity (BRS, expressed as change of interbeat interval per change in BP) is intact after focal seizures, whereas BRS is markedly impaired in the early postictal period following generalized convulsive seizures (GCS), possibly due to metabolically mediated muscular hyperemia in skeletal muscles, a massive release of catecholamines and compromised brain stem function. Whilst most SUDEP cases are probably caused by a cardiorespiratory failure during the early postictal period following GCS, a profoundly disturbed BRS may allow a life-threatening drop of systemic BP in the aftermath of GCS, as recently reported in a patient as a plausible cause of SUDEP in a few patients.