Interictal 12-lead electrocardiography in patients with epilepsy

Sudden Cardiac Death or Ventricular Arrythmia in Patients Taking Levetiracetam or Oxcarbazepine

BACKGROUND AND OBJECTIVES

Levetiracetam is a widely used antiseizure medication. Recent concerns have been raised regarding the potential prolongation of the QT interval by levetiracetam and increased risk of sudden cardiac death. This could have profound implications for patient safety and for prescribing practice. This study assessed the potential association of levetiracetam with cardiac outcomes related to QT interval prolongation. We compared outcomes of patients taking levetiracetam with those taking oxcarbazepine as a comparator medication that has not been associated with prolongation of the QT interval.

METHODS

The sample included patients who were newly prescribed levetiracetam or oxcarbazepine from January 31, 2010, to December 31, 2019, using administrative claims data from the OptumLabs Data Warehouse (OLDW). The analysis focused on a combined endpoint of sudden cardiac death or ventricular arrythmia, which are both linked to QT interval prolongation. We used a new user design and selected oxcarbazepine as an active comparator with levetiracetam to minimize bias. We used propensity score weighting to balance the levetiracetam and oxcarbazepine cohorts and then performed weighted Cox regressions to evaluate the association of levetiracetam with the combined endpoint.

RESULTS

We identified 104,655 enrollees taking levetiracetam and 39,596 enrollees taking oxcarbazepine. At baseline, enrollees taking levetiracetam were older, more likely to have diagnosed epilepsy, and more likely to have diagnosed comorbidities including hypertension, cerebrovascular disease, and coronary artery disease. In the main analysis, we found no significant difference between levetiracetam and oxcarbazepine in the rate of the combined endpoint for the Cox proportional hazards model (hazard ratio [HR] 0.79, 95% CI 0.42-1.47) or Cox regression with time-varying characteristics (HR 0.78, 95% CI 0.41-1.50).

DISCUSSION

When compared with oxcarbazepine, levetiracetam does not correlate with increased risk of ventricular arrythmia and sudden cardiac death. Our finding does not support the concern for cardiac risk to indicate restriction of levetiracetam use nor the requirement of cardiac monitoring when using it.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that sudden cardiac death and ventricular arrythmia are not more frequent in patients older than 17 years newly prescribed levetiracetam, compared with those prescribed oxcarbazepine.

Effect of levetiracetam therapy on electrocardiographic parameters

AIM

The purpose of this study was to compare the electrocardiographic parameters before and at the sixth month of treatment of patients diagnosed with epilepsy and who were started on levetiracetam therapy.

METHODS

The files of 30 patients diagnosed with epilepsy and on levetiracetam therapy were examined in this study. Clinical findings, electroencephalography (EEG), cranial magnetic resonance imaging (MRI) and electrocardiography (ECG) data before and at the sixth month of treatment were recorded.

RESULTS

The patients' mean age was 10.93 ± 3.74 (4-17) years; 16 (53.33%) patients were boys. In total, 13 (43.3%) were found to experience focal seizures, and 17 (56.7%) generalized epilepsy-type seizures. Comparison of the ECG parameters (PR interval, QTc, QT interval, and QRS duration) revealed a shortening in the PR interval and QTc values at the sixth month of treatment, although the changes were not statistically significant. No significant differences in terms of gender and epilepsy types were observed between the ECG parameters before treatment and at the sixth month (p > 0.05).

CONCLUSION

In this study, levetiracetam was found to have no effect on ECG parameters.

The value of QT interval in differentiating vasovagal syncope from epilepsy in children

BACKGROUND

Both vasovagal syncope (VVS) and epilepsy present with transient loss of consciousness and are often difficult to identify. Hence this study aimed to explore the value of QT interval in the differentiation of VVS and epilepsy in children.

METHODS

One hundred thirteen children with unexplained transient loss of consciousness were selected. 56 children with VVS (VVS group), including 37 males and 19 females, the average age is 9.88 ± 2.55 years old. 57 children with epilepsy (epilepsy group), including 36 males and 21 females, the average age is 8.96 ± 2.67 years old. At the same time, the 60 healthy individuals (control group) were examined according to age and sex. The QT interval of 12-lead electrocardiogram in a basal state of three groups was measured and statistically analyzed by SPSS 24.0 software.

RESULTS

Compared with the control group, (1) QTcmax, QTcmin and QTcd were significantly longer in VVS group (P < 0.05), QTmax and QTmin were significantly shorter in VVS group (P < 0.05), and there were no significant differences in QTd between the two groups (P > 0.05). (2) The QTmax and QTmin were significantly shorter in epilepsy group (P < 0.05), and there were no significant differences in QTd, QTcmax, QTcmin, QTcd between the two groups (P > 0.05). Compared with the epilepsy group, The QTcmax, QTcmin, QTcd were significantly longer in VVS group (P < 0.05), and there were no significant differences in QTd, QTmax, QTmin between the two groups (P > 0.05). When QTcmax > 479.84 ms, QTcmin > 398.90 ms and QTcd > 53.56 ms, the sensitivity and specificity of diagnosing VVS were 62.5% and 77.19%, 82.14% and 50.88%, 82.14% and 38.60% respectively.

CONCLUSION

QTcmax, QTcmin and QTcd have certain value in differentiating VVS from epilepsy in children.

Electrocardiography Findings in Children with Febrile Convulsion

Febrile convulsion (FC) is a seizure associated with body temperature that leads to electrocardiography changes. This article aimed to study electrocardiographic changes in children with FC as compared with healthy children. In this case–control study, 90 children aged 6 to 60 months were matched with equal healthy ones in “Ali Ebne Abi Talib” hospital in Zahedan, Iran. FC was confirmed by a neurologist based on its definition by the International League Against Epilepsy. Electrocardiogram (ECG) was captured by a pediatric cardiologist. Data were analyzed using SPSS 19. Sex distribution in groups was similar (p = 0.232). QT correction (QTc) was normal in 97.8 and 76.7% of controls and FC children, respectively (p < 0.001). QT dispersion (QTd) was normal in all controls when it was prolonged in 0.6% of children (p< 0.316). Calculated QT (QTcd) prolonged in controls and FC of 4.4 and 27.8% of children, respectively (p < 0.001). RR interval (p = 0.001), heart rate (p< 0.001), S in V1 (p = 0.004), R in aVL (p = 0.007), S in V3(p< 0.001), left ventricular mass (LVM) (p< 0.001), QTd (p< 0.001), QTc max (p< 0.001), and QTcd (p< 0.001) were significant. Means of LVM were 46.00 ± 1.86, 47.22 ± 2.24, and 51.45 ± 2.41 for age groups of <12, 12–24, and >24 months, respectively (p < 0.001). We conclude that QTd, QTc, and QTcd were higher in FC compared with those of healthy children. The rate of FC in children with higher level of QTcd increased compared with controls.

Electrocardiographic Abnormalities and Mortality in Epilepsy Patients

Background and Objectives: People with epilepsy (PWE) have a 2–3 times higher mortality rate than the general population. Sudden unexpected death in epilepsy (SUDEP) comprises a significant proportion of premature deaths, whereas sudden cardiac death (SCD) is among the leading causes of sudden death in the general population. Cardiac pathologies are significantly more prevalent in PWE. Whether electrocardiographic (ECG) parameters are associated with remote death in PWE has yet to be elucidated. The study objective was to assess whether interictal ECG parameters are associated with mortality in the long-term. Materials and Methods: The study involved 471 epilepsy patients who were hospitalized after a bilateral tonic-clonic seizure(s). ECG parameters were obtained on the day of hospitalization (heart rate, PQ interval, QRS complex, QT interval, heart rate corrected QT interval (QTc), ST segment and T wave changes), as well as reported ECG abnormalities. Mortality data were obtained from the Latvian National Cause-of-Death database 3–11, mean 7.0 years after hospitalization. The association between the ECG parameters and the long-term clinical outcome were examined. Results: At the time of assessment, 75.4% of patients were alive and 24.6% were deceased. Short QTc interval (odds ratio (OR) 4.780; 95% confidence interval (CI) 1.668–13.698; p = 0.004) was associated with a remote death. After the exclusion of known comorbidities with high mortality rates, short QTc (OR 4.631) and ECG signs of left ventricular hypertrophy (OR 5.009) were associated with a remote death. Conclusions: The association between routine 12-lead rest ECG parameters—short QTc interval and a pattern of left ventricular hypertrophy—and remote death in epilepsy patients was found. To the best of our knowledge, this is the first study to associate rest ECG parameters with remote death in an epileptic population.

Simultaneous electrocardiogram during routine electroencephalogram: arrhythmia rates through the eyes of the cardiologist

BACKGROUND

The importance of simultaneous 2-lead electrocardiogram (ECG) recording during routine electroencephalogram (EEG) has been reported several times on clinical grounds.

OBJECTIVE

To investigate arrhythmia rates detected by simultaneous 2-lead ECG in our patient sample undergoing routine EEG. Remarkably, we sought to assess the possible expansion of results with a more experienced interpretation of simultaneous ECG.

METHODS

Simultaneous 2-lead ECG recordings during routine EEG, performed between January and March, 2016, have been retrospectively analyzed by a cardiology specialist. In addition, EEG reports were screened with the keywords 'arrhythmia, tachycardia, bradycardia, atrial fibrillation, extrasystole' to evaluate the neurologist interpretation.

RESULTS

Overall, 478 routine EEG recordings were scanned. The mean age of the patients was 42.8±19.8 (16-95), with a sex ratio of 264/214 (F/M). In 80 (17%) patients, findings compatible with arrhythmia were identified on simultaneous ECG after a cardiologist's evaluation. The detected arrhythmia subtypes were: ventricular extrasystole (n=27; 5.6%), supraventricular extrasystole (n=23; 4.8%), tachycardia (n=9; 1.8%), prolonged QRS duration (n=7; 8.7%), atrial fibrillation (n=6; 1.2%), and block (n=6; 1.2%). On the other hand, keywords related to arrhythmia were present in 45 (9.4%) of EEG reports. The reported statements were tachycardia (3.3%), arrhythmia (2.5%), bradycardia (2.1%), and extrasystole (1.5%).

CONCLUSIONS

A considerably high rate of arrhythmia cases was determined on simultaneous ECG during routine EEG after being interpreted by a cardiologist. However, the screening results of EEG reports revealed relatively low arrhythmia rates. These results suggest that the detection rates of ECG abnormalities during routine EEG may be potentially improved.

Evaluation of electrocardiographic parameters in patients with epileptic seizure

The aim of the study is to evaluate the changes in electrocardiographic parameters, including QTc dispersion (QTcd), Tpeak-Tend (Tp-e)/QTc ratio and P-wave dispersion (Pd), during the period without seizure activation in patients, presented to the emergency department (ED) with epileptic seizures. This prospective case-control study was conducted between January 2017 and January 2018. Patients, over 18 years old and presented to the ED with epileptic seizure, were consecutively included in the study. Interictal period ECGs of patients were obtained at least 2 hours after the end of the postictal period. ST-segment changes, QT interval, corrected QT interval (QTc), QTd, Pd, Tp-e, Tp-e dispersion (Tp-ed), Tp-e/QTc ratio and arrhythmias were evaluated in interictal ECGs. A total of 103 epileptic patients and 31 control cases were included in the study. Heart rate, QTc, QTcd, Pd, Tp-ed and Tp-e/QTc ratio were significantly higher in the epilepsy group than in the control group (p < 0.05 for all values). No statistically significant difference in those parameters was observed between the patients with known epilepsy and the patients who had seizure for the first time. There was also no statistically significant difference between patients who had recurrent seizures during the observation period and who did not. The patients with epileptic seizures had increased Pd, QTd, QTcd, Tp-ed and Tpe/QTc ratio during interictal period compared to healthy subjects. These electrocardiographic changes might be associated with an increased risk of dysrhythmia. However, prospective large cohorts with short- and long-term follow-up are needed for clinical reflections.

Cardiac dysregulation following intrahippocampal kainate-induced status epilepticus

Status epilepticus (SE) is a prevalent disorder associated with significant morbidity, including the development of epilepsy and mortality. Cardiac arrhythmias (i.e. inappropriate sinus tachycardia and bradycardia, asystole, and atrioventricular blocks) are observed in patients following SE. We characterized ictal (during a seizure) and interictal (between seizure) cardiac arrhythmogenesis following SE using continuous electrocardiography and video electroencephalography (vEEG) recordings throughout a 14-day monitoring period in an intrahippocampal chemoconvulsant mouse model that develops epilepsy. We quantified heart rhythm abnormalities and examined whether the frequency of cardiac events correlated with epileptiform activity, circadian (light/dark) cycle, the presence of seizures, and survival during this period of early epileptogenesis (the development of epilepsy) following SE. Shortly following SE, mice developed an increased interictal heart rate and heart rhythm abnormalities (i.e. sinus pause and sinus arrhythmias) when compared to control mice. Heart rhythm abnormalities were more frequent during the light cycle and were not correlated with increased epileptiform activity or seizure frequency. Finally, SE animals had early mortality, and a death event captured during vEEG recording demonstrated severe bradycardia prior to death. These cardiac changes occurred within 14 days after SE and may represent an early risk factor for sudden death following SE.

Electrocardiographic changes associated with epilepsy beyond heart rate and their utilization in future seizure detection and forecasting methods

The ability to assess seizure risk may help provide timely warnings and more personalized treatment plans for people with epilepsy (PWE). ECG changes are commonly observed in epilepsy which make ECG a promising candidate to monitor seizure risk. Most ECG research in this domain has focused on heart rate-related changes. However, several studies have identified a range of other peri-ictal ECG parameter changes that may potentially prove useful for seizure detection and forecasting. Here, we offer a systematic review of ECG changes in epilepsy outside of heart rate. We performed the systematic literature review according to PRISMA guidelines using key words related to ECG, SUDEP and epilepsy. We identified and screened 502 abstracts, read 110 full papers, and included 24 papers in the final review. Our results suggest that PWE may be more prone to cardiac conduction abnormalities than healthy controls. During interictal periods, PWE were more likely to have abnormal QTc intervals, ST segment abnormalities, elevated T Waves, early repolarization (ER), increased P Wave dispersion and PR intervals when compared to controls. Apart from these baseline abnormalities, changes during the pre-ictal and ictal states have been reported, with arrhythmias, QTc prolongation and ST segment changes being the most common. A better understanding of these state-dependent changes may afford less-cumbersome and less-stigmatizing epilepsy monitoring tools in the future.

Effects of Chronic Carbamazepine Treatment on the ECG in Patients with Focal Seizures

Background and Objectives

Several mechanisms have been proposed for the sudden unexpected death in epilepsy patients, such as cardiac arrhythmias, a decrease in heart rate variability and the use of anti-epileptic drugs (AEDs). Although carbamazepine is commonly used as an AED, the exact working mechanism of this drug as well as its effect on the heart are not completely understood. The aim of this study was to determine whether chronic carbamazepine therapy in patients with focal seizures and impaired awareness has an effect on the electrocardiogram (ECG).

Subjects and Methods

This cross-sectional study included 36 patients with focal seizures and impaired awareness treated for 12–32 months with carbamazepine monotherapy and 38 healthy volunteers. A 5-min modified three-electrode chest lead ECG with lead II configuration was recorded using LabChart 7 ECG software module at 1000-Hz sampling frequency. All data analysis was performed using custom-made Matlab 2015b scripts. ECGs of patients and controls were compared with respect to heart rate, time intervals and measures of short- and long-term variation.

Results

There were no significant differences in heart rate and ECG time intervals between the patient and control groups. Measures on short- and long-term variability also did not show any significant group differences.

Conclusion

Our study shows that chronic use of carbamazepine as monotherapy does not have any significant effects on ECG time intervals or measures of short- and long-term variability.

Interictal cardiac repolarization abnormalities in people with epilepsy

BACKGROUND AND OBJECTIVE

The occurrence of cardiac electrical abnormalities such as repolarization disorders in patients with epilepsy was previously documented and may, in part, clarify the mechanism of sudden unexpected death in those patients. The aim of this study was to investigate the frequency of cardiac repolarization disorders among patients with epilepsy and whether specific demographic- or disease-related features were associated with their occurrence.

SUBJECTS AND METHODS

This cross-sectional study was carried out on 1000 subjects with epilepsy who were compared with age- and sex-matched 2500 subjects without epilepsy. Clinical assessment, which included careful history taking and examination, was carried out for all participants in addition to resting 12-lead electrocardiogram (ECG) recording. Electrocardiograms were reviewed by experienced cardiologists. Electrocardiogram intervals were measured, and morphological abnormalities were identified using standard guidelines.

RESULTS

Repolarization abnormalities were found in 142 (14.2%) patients with epilepsy. A statistically significant elevation in percentage of corrected QT interval (QTc) prolongation (both severe and borderline) among patients with epilepsy compared with controls was documented (8.4% vs 2%, P<0.001). Epilepsy increased the likelihood of hosting prolonged QTc more than 4 times (95% confidence interval: 3.175-6.515; odds ratio: 4.548; P<0.001). Affected patients were significantly older (95% confidence interval: 1.012-1.044; odds ratio: 1.027; P=0.001), and the abnormality was significantly more prevalent among those with poor seizure control (95% confidence interval: 1.103-2.966; odds ratio: 1.809; P=0.019). On the other hand, early repolarization (ER) pattern and Brugada type ECG pattern (BP) were significantly more prevalent in subjects without epilepsy.

CONCLUSIONS

Corrected QT interval prolongation (both severe and borderline) was more prevalent among patients with epilepsy, especially if uncontrolled or elderly. Electrocardiogram should be established as a part of the diagnostic workup of epilepsy in order to identify such electrocardiographic abnormality.

Determining factors of electrocardiographic abnormalities in patients with epilepsy: A case-control study

Sudden unexpected death in epilepsy (SUDEP) is a major cause of mortality in young patients with epilepsy (PWE). Although its mechanisms are still poorly understood, they may include cardiorespiratory dysfunction. Standard 12-lead electrocardiograms (ECGs) were obtained from 62 consecutive patients (aged 18-66y) with a definite diagnosis of epilepsy, without seizures at the day of ECG, and 57 healthy controls matched for sex, age and body mass index (BMI). All ECGs were evaluated by a blinded board-certified cardiologist. Patients with symptomatic focal epilepsy represented 90.3% (N=56), of whom 56.4% (N=35) had temporal lobe epilepsy, with a mean duration of 22.02±14.96years of epilepsy. We observed more prolonged P-wave (p<0.0001) and PR interval (p=0.01) in patients than in controls. Additionally, longer QT intervals (p<0.01), pathologic QT dispersion (p<0.01) and left atrial overload (p<0.01) were more common in PWE. Multiple linear regression analysis evidenced age, gender and polytherapy as factors associated with altered ECG. Therefore, routine ECG should be requested in PWE, especially for males, increasing age and in polytherapy. Findings such as longer PR and QT interval, and pathologic QT dispersion, may reflect cardiac structural changes and/or autonomic nervous system dysfunction and indicate a risk for SUDEP.

The pathophysiology of cardiac dysfunction in epilepsy

Alterations in cardiac electrophysiology are an established consequence of long-standing drug resistant epilepsy. Patients with chronic epilepsy display abnormalities in both sinoatrial node pacemaker current as well as ventricular repolarizing current that places them at a greater risk of developing life-threatening cardiac arrhythmias. The development of cardiac arrhythmias secondary to drug resistant epilepsy is believed to be a key mechanism underlying the phenomenon of Sudden Unexpected Death in EPilepsy (SUDEP). Though an increasing amount of studies examining both animal models and human patients have provided evidence that chronic epilepsy can detrimentally affect cardiac function, the underlying pathophysiology remains unclear. Recent work has shown the expression of several key cardiac ion channels to be altered in animal models of genetic and acquired epilepsies. This has led to the currently held paradigm that cardiac ion channel expression may be secondarily altered as a consequence of seizure activity-resulting in electrophysiological cardiac dysfunction. Furthermore, cortical autonomic dysfunction - resulting from seizure activity-has also been suggested to play a role, whereby seizure activity may indirectly influence cardiac function via altering centrally-mediated autonomic output to the heart. In this review, we discuss various cardiac dysrhythmias associated with seizure events-including tachycardia, bradycardia and QT prolongation, both ictally and inter-ictally, as well as the role of the autonomic nervous system. We further discuss key ion channels expressed in both the heart and the brain that have been shown to be altered in epilepsy and may be responsible for the development of cardiac dysrhythmias secondary to chronic epilepsy.

Polytherapy with sodium channel-blocking antiepileptic drugs is associated with arrhythmogenic ST-T abnormality in patients with epilepsy

PURPOSE

Recent reports have documented the appearance of Brugada-type ST elevation in cases of overdose of antiepileptic drugs (AEDs). However, little is known about changes on electrocardiographs (ECGs) during AED use at therapeutic doses. AEDs may cause Brugada-type ST elevation or J-wave-like intraventricular conduction delays through an ion channel-blocking effect. In the present study, we sought to elucidate ECG abnormalities in patients on AED therapy.

METHODS

The study population consisted of 120 consecutive patients with epilepsy who continued to take AEDs and had ECGs recorded during these therapies. Their clinical background and ECGs were retrospectively analyzed. Brugada-type ST elevation was classified according to the consensus report on Brugada syndrome. A J-wave-like ECG abnormality was defined as the appearance of notching or slurring of the QRS complex (>0.1mV) in the inferior/lateral leads.

RESULTS

Of the 120 patients, 15 (12.5%) exhibited Brugada-type ST elevation and 35 (29.2%) showed a J-wave-like ECG abnormality. Polytherapy with sodium channel-blocking AEDs (e.g., carbamazepine, phenytoin, lamotrigine) was more frequently observed in patients with Brugada-type ST elevation (p=0.048). However, the serum concentrations of these medicines did not differ between patients with and without ECG abnormalities (carbamazepine: 7.9±4.1 vs. 7.2±5.9μg/dL; phenytoin: 12.7±4.1 vs. 15.5±9.5μg/dL, NS).

CONCLUSION

ST-T abnormalities were frequently seen in patients using AEDs. The presence of Brugada-type ST elevation was associated with polytherapy with sodium channel-blocking AEDs.

Who to target in sudden unexpected death in epilepsy prevention and how? Risk factors, biomarkers, and intervention study designs

The risk of dying suddenly and unexpectedly is increased 24- to 28-fold among young people with epilepsy compared to the general population, but the incidence of sudden unexpected death in epilepsy (SUDEP) varies markedly depending on the epilepsy population. This article first reviews risk factors and biomarkers for SUDEP with the overall aim of enabling identification of epilepsy populations with different risk levels as a background for a discussion of possible intervention strategies. The by far most important clinical risk factor is frequency of generalized tonic-clonic seizures (GTCS), but nocturnal seizures, early age at onset, and long duration of epilepsy have been identified as additional risk factors. Lack of antiepileptic drug (AED) treatment or, in the context of clinical trials, adjunctive placebo versus active treatment is associated with increased risks. Despite considerable research, reliable electrophysiologic (electrocardiography [ECG] or electroencephalography [EEG]) biomarkers of SUDEP risk remain to be established. This is an important limitation for prevention strategies and intervention studies. There is a lack of biomarkers for SUDEP, and until validated biomarkers are found, the endpoint of interventions to prevent SUDEP must be SUDEP itself. These interventions, be they pharmacologic, seizure-detection devices, or nocturnal supervision, require large numbers. Possible methods for assessing prevention measures include public health community interventions, self-management, and more traditional (and much more expensive) randomized clinical trials.

Effects of phenobarbital and levetiracetam on PR and QTc intervals in patients with post-stroke seizure

BACKGROUND AND OBJECTIVES

Sudden unexplained/unexpected death (SUDEP) is related to high mortality in patients with epilepsy. The prolongation of QT interval, involved in cardiac arrhythmia-related SUDEP, may be precipitated by antiepileptic drugs (AEDs). In this study, we evaluated the effects of phenobarbital and levetiracetam on PR-QTc intervals in patients with post-stroke seizures.

METHODS

We performed an open-label, parallel group, prospective, multicenter study between June 2009 and December 2013 in patients older than 18 years of age with a clinical diagnosis of post-stroke seizure and treated with phenobarbital or levetiracetam. In order to exclude a role of cerebral post-stroke injury on modulation of PR and QTc intervals, patients with cerebral post-stroke injury and without seizures were also enrolled as controls.

RESULTS

Interictal electrocardiography analysis revealed no significant difference in PR interval between patients treated with an AED (n = 49) and control patients (n = 50) (181.25 ± 12.05 vs. 182.4 ± 10.3 ms; p > 0.05). In contrast, a significantly longer QTc interval was recorded in patients treated with an AED compared with control patients (441.2 ± 56.6 vs. 396.8 ± 49.3 ms; p < 0.01). Patients treated with phenobarbital showed a significantly longer QTc interval than patients treated with levetiracetam (460.0 ± 57.2 vs. 421.5 ± 50.1 ms; p < 0.05).

CONCLUSIONS

The study reported that in patients with late post-stroke seizures, phenobarbital prolonged QTc interval more so than levetiracetam.

Increased prevalence of ECG markers for sudden cardiac arrest in refractory epilepsy

BACKGROUND AND AIM

People with epilepsy are at increased risk of sudden cardiac arrest (SCA) due to ECG-confirmed ventricular tachycardia/fibrillation, as seen in a community-based study. We aimed to determine whether ECG-risk markers of SCA are more prevalent in people with epilepsy.

METHODS

In a cross-sectional, retrospective study, we analysed the ECG recordings of 185 people with refractory epilepsy and 178 controls without epilepsy. Data on epilepsy characteristics, cardiac comorbidity, and drug use were collected, and general ECG variables (heart rate (HR), PQ and QRS intervals) assessed. We analysed ECGs for three markers of SCA risk: severe QTc prolongation (male >450 ms, female >470 ms), Brugada ECG pattern, and early repolarisation pattern (ERP). Multivariate regression models were used to analyse differences between groups, and to identify associated clinical and epilepsy-related characteristics.

RESULTS

People with epilepsy had higher HR (71 vs 62 bpm, p<0.001) and a longer PQ interval (162.8 vs 152.6 ms, p=0.001). Severe QTc prolongation and ERP were more prevalent in people with epilepsy (QTc prolongation: 5% vs 0%; p=0.002; ERP: 34% vs 13%, p<0.001), while the Brugada ECG pattern was equally frequent in both groups (2% vs 1%, p>0.999). After adjustment for covariates, epilepsy remained associated with ERP (ORadj 2.4, 95% CI 1.1 to 5.5) and severe QTc prolongation (ORadj 9.9, 95% CI 1.1 to 1317.7).

CONCLUSIONS

ERP and severe QTc prolongation appear to be more prevalent in people with refractory epilepsy. Future studies must determine whether this contributes to increased SCA risk in people with epilepsy.

Dispersion durations of P-wave and QT interval in children treated with a ketogenic diet

BACKGROUND

Limited data are available on the effects of a ketogenic diet on dispersion duration of P-wave and QT-interval measures in children. We searched for the changes in these measures with serial electrocardiograms in patients treated with a ketogenic diet.

METHODS

Twenty-five drug-resistant patients with epilepsy treated with a ketogenic diet were enrolled in this study. Electrocardiography was performed in all patients before the beginning and at the sixth month after implementation of the ketogenic diet. Heart rate, maximum and minimum P-wave duration, P-wave dispersion, and maximum and minimum corrected QT interval and QT dispersion were manually measured from the 12-lead surface electrocardiogram.

RESULTS

Minimum and maximum corrected QT and QT dispersion measurements showed nonsignificant increase at month 6 compared with baseline values. Other previously mentioned electrocardiogram parameters also showed no significant changes.

CONCLUSIONS

A ketogenic diet of 6 months' duration has no significant effect on electrocardiogram parameters in children. Further studies with larger samples and longer duration of follow-up are needed to clarify the effects of ketogenic diet on P-wave dispersion and corrected QT and QT dispersion.