Clinical cues for detecting ictal asystole

Objective The occurrence of asystole during an epileptic seizure is the most dramatic manifestation of ictal bradycardia. Recognition of ictal asystole is important as treatment with both antiepileptic drugs and cardiac pacing may be necessary. The purpose of this study was to identify clinical cues to aid in the detection of ictal asystole. Methods We analyzed the clinical and electrophysiologic features of all recorded seizures in consecutive patients diagnosed with ictal bradycardia and asystole on prolonged video-EEG/ECG monitoring over a 14 year period. Results Twenty-nine seizures with ictal bradycardia were identified in 13 patients. Of these, 11 seizures in seven patients were associated with asystole. Bilateral transient limb movements consisting of asymmetric posturing or jerking occurred during eight episodes of ictal asystole, and loss of muscle tone occurred during four. In contrast, neither bilateral limb movement nor loss of muscle tone was observed in any of the non-asystolic seizures, whether ictal bradycardia was present or not. All patients with ictal asystole reported a history of seizure-related falls and brief body and limb jerking. Conclusions The presence of loss of muscle tone or bilateral asymmetric jerky limb movements during a seizure suggests the possibility of ictal asystole. Video-EEG/ECG monitoring should be considered in patients with epilepsy demonstrating these clinical features to determine if ictal asystole is present.     

Ictal asystole in a patient with posterior reversible encephalopathy syndrome (PRES) and seizures

We describe a case of ictal asystole in a patient with posterior reversible encephalopathy syndrome (PRES), which has never been described previously. Ictal asystole is rare and has possible serious medical consequences, including syncope, and may be a potential mechanism for sudden unexpected death in epilepsy (SUDEP). Awareness that PRES may be observed with recurrent ictal asystole may aid in the recognition and treatment of seizures in this condition and the prevention of asystole‐associated complications.     

Ictal asystole in temporal lobe epilepsy before and after pacemaker implantation.

Events of ictal bradycardia or asystole may be of relevance in epilepsy patients presenting with ictal falls, and are a potential contributor to SUDEP. The literature on ictal bradycardia or asystole is anecdotal and consists of case reports and small case series. There are no guidelines for the care of patients with ictal arrhythmias. Insertion of cardiac pacemakers may prevent life-threatening cardiac arrest, syncope and trauma.We report the case of a 41-year-old man who presented with refractory partial seizures resulting in syncope leading to severe head trauma, as the only ictal semiology. During presurgical video-EEG monitoring, two episodes of ictal bradycardia followed by asystole and syncope were recorded. A cardiac pacemaker was implanted. At the nine-month follow-up, the patient reported no overt seizures, syncopes or traumatic falls. Our case demonstrates that implantation of a cardiac pacemaker while continuing AEDs may render a patient free from ictal symptoms and prevent ictal syncope and subsequent trauma. [Published with video sequences].     

Serial and prolonged EEG monitoring in anti-N-Methyl-d-Aspartate receptor encephalitis

ObjectiveTo describe serial electroencephalographic (EEG) findings of three patients with anti-NMDAR encephalitis.MethodsThree women (age 15–34 years) with confirmed anti-NMDAR encephalitis underwent serial EEG recordings. Continuous EEG for 72 h was performed in one case and 3-day video-EEG monitoring was obtained in two cases.ResultsGeneralized rhythmic delta activity (GRDA) was found in all patients. GRDA persisted for hours, but was not continuous on a 24-h EEG recording, disclosed no frequency, voltage or field evolution, and was not seen on the first EEG of two patients. Extreme delta brush was noted in two patients who presented more severe disease. One patient presented seizures, which were electrographically and clinically different from the GRDA pattern and from dyskinetic movements.ConclusionsSerial or continuous EEG may be necessary to detect GRDA in anti-NMDAR patients. To avoid unnecessary treatment, this pattern should not be interpreted as indicative of ictal activity, unless there is evidence of its ictal nature.SignificanceOur findings may contribute to the diagnosis of anti-NMDAR encephalitis in cases with characteristic clinical picture.     

Comparison of clinical and electrophysiological characteristics between ictal and cardiac asystole encountered during video-EEG monitoring

Aims. Differentiation between syncope secondary to epileptic seizures and cardiac disease in patients displaying transient loss of consciousness associated with convulsive movements is a diagnostic challenge both for neurologists and cardiologists. In such patients, prolonged video-EEG monitoring not only helps in identifying asystole as the cause of syncope, but also in categorizing asystole as primarily cardiac in origin (cardiac asystole) and secondary to epileptic seizures (ictal asystole). We carried out this study to ascertain the prevalence of asystole in an epilepsy monitoring unit, and to contrast the clinical and electrophysiological characteristics between ictal asystole and cardiac asystole. Methods. Through a retrospective search, we identified patients who were shown to have had asystole using a database of patients who underwent prolonged video-EEG monitoring during a 68-month period. We compared the data of 18 consecutive patients; five with ictal asystole and 13 with cardiac asystole, with 121 and 64 events recorded from them, respectively. Results. Of the 10,096 patients who underwent prolonged video-EEG monitoring during the study period, we identified 18 (0.17%) patients with asystole. Cardiac asystole was 2.6 times more frequent than ictal asystole. Older age at onset, heralding symptoms of presyncope, occurrence during wakefulness, and brief duration of the events supported the diagnosis of cardiac asystole. Ictal asystole events were more protracted, and prolonged asystole more frequently occurred in patients with extratemporal seizures compared to temporal lobe seizures. Asystole occurred in only half of the recorded seizures. Conclusions. The accurate categorization of asystole as seizure-related or heart disease-related has huge implications for management strategy and outcome. The necessity of permanent pacemaker implantation is more frequent and urgent in patients with cardiac asystole because of the greater risk of sudden death. Hence, in patients with an ominous diagnosis of cardiac asystole, a thorough cardiac evaluation should surpass neurological evaluation.     

Cardiac asystole in epilepsy: clinical and neurophysiologic features

PURPOSE: Cardiac asystole provoked by epileptic seizures is a rare but important complication in epilepsy and is supposed to be relevant to the pathogenesis of sudden unexplained death in epilepsy (SUDEP). We sought to determine the frequency of this complication in a population of patients with medically intractable epilepsy and to analyze the correlation between EEG, electrocardiogram (ECG), and clinical features obtained from long-term video-EEG monitoring. METHODS: Retrospective analysis of the clinical records of hospitalized patients from May 1992 to June 2001 who underwent long-term video-/EEG monitoring. RESULTS: Of a total of 1,244 patients, five patients had cardiac asystole in the course of ictal events. In these patients, 11 asystolic events, between 4 and 60 s long in a total of 19 seizures, were registered. All seizures had a focal origin with simple partial seizures (n = 13), complex partial seizures (n = 4), and secondarily generalized seizures (n = 2). One patient showed the longest asystole ever reported (60 s) because of a seizure. Cardiac asystole occurred in two patients with left-sided temporal lobe epilepsy (TLE) and in three patients with frontal lobe epilepsy (FLE; two left-sided, one bifrontal). Two patients reported previous cardiac disease, but only one had a pathologic ECG by the time of admission. Two patients had a simultaneous central ictal apnea during the asystole. None of the patients had ongoing deficits due to the asystole. CONCLUSIONS: These findings confirm that seizure-induced asystole is a rare complication. The event appeared only in focal epilepsies (frontal and temporal) with a lateralization to the left side. A newly diagnosed or known cardiac disorder could be a risk factor for ictal asystole. Abnormally long postictal periods with altered consciousness might point to reduced cerebral perfusion during the event because of ictal asystole. Central ictal apnea could be a frequent associated phenomenon.     

Cardiac asystole during right frontal lobe seizures: a case report

Abstract The association between partial seizures and cardiac asystole has rarely been reported in the literature. This potentially life-threatening symptom has been observed principally in left-sided epilepsies, in particular during seizures originating in temporal lobe. We describe a case with ictal bradycardia followed by cardiac asystole during right frontal lobe seizures. Video-EEG monitoring recorded two partial seizures with electro-clinical findings suggestive of a right frontal lobe origin, associated with ictal bradycardia followed by prolonged asystole. The brain MRI showed a lesion located in the cingulate gyrus of the right frontal lobe. The patient required a subsequent placement of a pacemaker. In conclusion, cardiac asystole may be a potentially life-threatening symptom during seizures of frontal lobe origin. The right fronto-mesial structures may play a role in autonomic regulation of cardiovascular responses.     

Ictal asystole mimicking seizure deterioration in temporal lobe epilepsy

We report on a patient with temporal lobe epilepsy, secondary to a left lateral temporal cavernoma, in whom the change in seizure semiology suggested recurrence of secondary generalized seizures. Anticonvulsive medication previously controlled secondary generalized seizures over a period of years but focal seizures continued at a lower rate. Continuous video‐EEG monitoring revealed ictal asystole associated with myoclonic syncope and falls during focal seizures arising from the left temporal lobe. After implantation of a cardiac pacemaker, no more falls occurred during the focal seizures. In conclusion, recurrence of seizure‐associated falls is typically attributed to recurrence of secondary generalized seizures, however, ictal asystole should be considered in selected epilepsy patients as a differential diagnosis of falls. [Published with video sequence]     

Cardiac asystole during a temporal lobe seizure

The association between temporal lobe seizures and cardiac arrhythmias has been anecdotally reported in the literature. Ictal bradycardia and cardiac asystole are rare, and maybe underestimated. The physiological mechanism is poorly understood. We report a patient with left temporal lobe seizures who developed ictal bradycardia and cardiac asystole during a complex partial seizure and required a subsequent placement of a pacemaker.     

The association of cardiac asystole with partial seizures: does it result from ictal or interictal activity?

Bradycardia or asystole that occur during some seizures may be life threatening as a leading cause of SUDEP. A patient with right and left temporal lobe onset seizures and preceding bardycardia or asystole is presented. He had bilateral hippocampal atrophy on MRI. The unreliability of ictal bradycardia or asystole as a lateralizing sign in patients with partial epilepsy and the role of interictal autonomic activity in heart rate changes during seizures are discussed.     

Late relapse of anti-N-methyl-d-aspartate receptor encephalitis with amusia and transiently reduced uptake in 123I-iomazenil single-photon emission computed tomography

IntroductionAnti-N-methyl-d-aspartate receptor (NMDAR) encephalitis has a high relapse rate at approximately 10–20%. Most relapses occur within 2 years from onset, and 5 years after onset is rare. We report a case of anti-NMDAR encephalitis relapse with amusia 10 years after the initial encephalitis and discuss the usefulness of ¹²³I-iomazenil single-photon emission computerized tomography (IMZ-SPECT) for its diagnosis.CaseA 13-year-old left-handed girl presented with a depressed level of consciousness and focal to bilateral tonic-clonic seizures. Cerebrospinal fluid (CSF) analysis showed a mildly increased white blood cell count, elevated neopterin levels, and positive oligoclonal bands. Brain MRI was normal. IMZ-SPECT revealed reduced uptake in the right frontoparietal region. She received intravenous pulse methylprednisolone (IVMP) and high-dose intravenous immunoglobulin for autoimmune encephalitis; her symptoms resolved without neurological deficits. At 23 years old, she had mild right-sided numbness, dysarthria, amusia, and tonic-clonic seizures. Although the CSF analysis and brain MRI were normal, IMZ-SPECT revealed reduced uptake, indicating a relapse of encephalitis. IVMP administration resolved the symptoms. After discharge, the initial and relapse CSF analysis revealed anti-NMDAR antibodies.ConclusionAn anti-NMDAR encephalitis relapse 10 years after onset has never been reported. IMZ-SPECT may help in the diagnosis of anti-NMDAR encephalitis.     

Relapsing Anti-NMDAR Encephalitis after a gap of eight years in a girl from North-East India

It has been just 7 years since the discovery of anti-NMDAR encephalitis as distinct immune-mediated encephalitis and we have such cases being reported from our country. Herein, we describe a case of a 13-year-old girl who had relapsing encephalitis consisting of multiple types of difficult-to-control seizures, abnormal behavior, language disintegration, memory loss and abnormal movements eight years after the first clinical attack. In 2005, when she was 5 yearsold, anti-NMDAR encephalitis was not yet discovered and she was provisionally diagnosed as a case of viral encephalitis. During her second attack in 2013, antibodies against NMDAR were demonstrated by immunofluoresence in serum (1:10). This is the first report from our country of a case of relapsing anti-NMDAR encephalitis of such a long duration, successfully treated by immunotherapy.     

Cerebral arrhythmia influencing cardiac rhythm: a case of ictal bradycardia.

Partial seizures of temporal origin can be associated with clinically significant tachycardia or bradycardia. Ictal bradycardia and asystole has been implicated in the etiology of sudden unexpected death in epileptic patients (SUDEP). Although symptomatic ictal bradycardia has been relatively well described in the literature; information on asymptomatic ictal bradycardia is scarce. We report a case of asymptomatic ictal bradycardia diagnosed during video EEG telemetry that was subsequently implanted with a cardiac pacemaker.     

Late onset ictal asystole in refractory epilepsy

Ictal asystole is a cardiac phenomenon associated with epileptic seizures, and may play a role in sudden unexplained death in epilepsy. We present a 17-year-old boy with chronic intractable epilepsy and a vagus nerve stimulator who developed ictal asystole many years after the onset of epilepsy. The asystole was not linked to the vagus nerve stimulator, and ultimately necessitated the placement of a cardiac pacemaker. A cardiac pacemaker and vagus nerve stimulator can be safely used simultaneously after careful testing during placement. The onset of asystolic events many years after the onset of epilepsy suggests that repeated seizures may exert long-term effects on cardiac function.     

GAD65 antibody‐associated autoimmune epilepsy with unique independent bitemporal‐onset ictal asystole

Antibodies against the 65‐kDa isoform of the intracellular enzyme, glutamate decarboxylase (GAD65), have been found in patients with limbic encephalitis and drug‐resistant autoimmune epilepsy. We report a 22‐year‐old female who presented with new‐onset seizures and neuropsychiatric symptoms. Video‐EEG captured unique, independent bitemporal‐onset focal seizures with impaired awareness and ictal asystole. An autoimmune epilepsy panel revealed elevated GAD65 antibodies in the serum (225 nmol/l) and CSF (2.78 nmol/l), while [¹⁸F]‐fluoro‐deoxy‐glucose positron emission tomography showed bitemporal hypometabolism (left > right). The patient was diagnosed with GAD65 antibody‐associated autoimmune epilepsy. Our observation adds to the spectrum of neurocardiac syndromes associated with autoimmune epilepsy.     

Anti-N-Methyl-D-Aspartate Encephalitis With Ovarian Cystadenofibroma

We report the case of an adolescent girl with anti-N-methyl-D-aspartate-receptor (NMDAR) encephalitis who presented with focal seizures and hemichorea, followed by agitation, speech disturbance, mutism, and autonomic dysfunction. The institution of immunotherapy and removal of an ovarian cystadenofibroma led to full resolution of her symptoms with disappearance of serum NMDAR antibodies. This is the first report linking ovarian cystadenofibroma to anti-NMDAR encephalitis.     

Early seizure termination in ictal asystole

To evaluate the association between cerebral hypoperfusion and seizure termination, we compared seizure duration in seven patients with syncopal ictal asystole (IA), seven with non-syncopal ictal bradycardia, and ten with non-bradycardic seizures. Mean seizure duration was 34.4±13 s in IA, 67±28.9 s in ictal bradycardia, and 82.1±31.1 in non-bradycardic seizures. These were significantly different (ANOVA, p<0.02). This suggests cerebral hypoxia-ischemia favors seizure termination.     

Anti-N-Methyl-D-Aspartate Receptor Encephalitis in Korea: Clinical Features,Treatment, and Outcome

Background and Purpose

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is the most common type of autoimmune synaptic encephalitis and it often responds to treatment. We analyzed the clinical characteristics of anti-NMDAR encephalitis in Korea.

Methods

Serum and/or cerebrospinal fluid (CSF) of adult patients (aged ≥18 years) with encephalitis of undetermined cause were screened for anti-NMDAR antibodies using a cell-based indirect immunofluorescence assay. The patients came from 41 university hospitals.

Results

Of the 721 patients screened, 40 were identified with anti-NMDAR antibodies and clinical details of 32 patients were obtained (median age, 41.5 years; 15 females). Twenty-two patients (68.8%) presented with psychiatric symptoms, 16 (50%) with seizures, 13 (40.6%) with movement disorders, 15 (46.9%) with dysautonomia, 11 (34.4%) with memory disturbance, and 11 (34.4%) with speech disturbance. Magnetic resonance imaging, electroencephalography, and CSF examinations yielded nonspecific findings. Tumor information was only available for 22 patients: 5 patients had tumors, and 2 of these patients had ovarian teratomas. Twenty-two patients received immunotherapy and/or surgery, and therapeutic responses were analyzed in 21 patients, of which 14 (66.7%) achieved favorable functional outcomes (score on the modified Rankin Scale of 0-2).

Conclusions

This study investigated the clinical characteristics of adult anti-NMDAR encephalitis in Korea. Currently, elderly patients who do not have tumors are commonly diagnosed with this condition. Understanding the detailed clinical characteristics of this disease will improve the early detection of anti-NMDAR encephalitis in patients both young and old.     

Anoxia–ischemia: A mechanism of seizure termination in ictal asystole

Cerebral anoxia–ischemia (CAI) is a potent inhibitor of cerebral hyperactivity and a potential mechanism of seizure self-termination. Prolonged ictal asystole (IA) invariably leads to CAI and has been implicated as a potential cause of sudden unexplained death in epilepsy (SUDEP). IA was seen in eight consecutive patients (0.12% of all patients monitored). Ten of their seizures with IA had evidence of CAI on electroencephalography (EEG), manifested by bilateral hypersynchronous slowing (BHS), and were compared to 18 seizures without signs of CAI. The ictal EEG pattern resolved in all 10 CAI events with onset of the BHS. The period from IA onset to seizure end was reduced in events with BHS compared to events without BHS (10.5 s vs. 28.3 s, respectively; p = 0.005), and the total seizure duration tended to be shorter. Anoxia–ischemia as a result of IA may represent an effective endogenous mechanism for seizure termination and may explain why the hearts of patients with ictal asystole reported to date in the literature resumed beating spontaneously.     

Temporal lobe seizures triggering recurrent syncope by ictal asystole

Described here is a case of a patient with left temporal lobe epilepsy and recurrent complex partial seizures associated with asystole. The posturing and myoclonus caused by the nonepileptogenic syncope during the asystole gave the appearance of secondary generalization prompting a surgical evaluation. A distinct atonic phase that interrupts the transition from a complex partial semiology to generalization is a critical clue to the presence of ictal asystole and is easily detected by video/EEG monitoring.