Epilepsy duration is an independent factor for electrocardiographic changes in pediatric epilepsy

Associations between epilepsy, respiratory impairment, and minor ECG abnormalities in children

OBJECTIVE

We sought to examine the effects of acute seizures and respiratory derangement on the cardiac electrical properties reflected on the electrocardiogram (ECG); and to analyze their potential interactions with a diagnosis of epilepsy in children.

METHODS

Emergency center (EC) visits with seizure or epilepsy diagnostic codes from 1/2011-12/2013 were included if they had ECG within 24 h of EC visit. Patients were excluded if they had pre-existing cardiac conditions, ion channelopathy, or were taking specific cardiac medications. Control subjects were 1:1 age and gender matched. Abnormal ECG was defined as changes in rhythm, PR, QRS, or corrected QT intervals; QRS axis or morphology; ST segment; or T wave morphology from normal standards. We identified independent associations between clinical factors and abnormal ECG findings using multivariable logistic regression modeling.

RESULTS

Ninety-five children with epilepsy presented to the EC with seizures, respiratory distress, and other concerns. Three hundred children without epilepsy presented with seizures. There was an increased prevalence of minor ECG abnormalities in children with epilepsy (49 %) compared to the control subjects (29 %) and those without epilepsy (36 %). Epilepsy (OR: 1.61, 95 %CI: 1.01-2.6), need for supplemental oxygen (OR 3.06, 95 % CI: 1.45-6.44) or mechanical ventilation (OR: 2.5, 95 % CI: 1.03-6.05) were independently associated with minor ECG abnormalities. Secondary analyses further demonstrated an independent association between level of respiratory support and ECG abnormalities only in the epilepsy group.

SIGNIFICANCE

Independent association of increased respiratory support with minor ECG abnormalities suggests a potential respiratory influence on the hearts of children with epilepsy.

Association of minor electrocardiographic (ECG) abnormalities with epilepsy duration in children: A manifestation of the epileptic heart?

PURPOSE

Cardiac abnormalities resulting from chronic epilepsy ("the epileptic heart") constitute a well-recognized comorbidity. However, the association of cardiac alterations with epilepsy duration remains understudied. We sought to evaluate this association using electrocardiogram (ECG).

METHODS

We prospectively enrolled children between 1 months and 18 years of age without known cardiac conditions or ion channelopathies during routine clinic visits. ECGs were categorized as abnormal if there were alterations in rhythm; PR, QRS, or corrected QT interval; QRS axis or morphology; ST segment or T wave. An independent association between ECG abnormalities and epilepsy duration was evaluated using multivariable logistic regression modeling.

RESULTS

213 children were enrolled. 100 ECGs (47%) exhibited at least one alteration; most commonly in the ST segment (37, 17%) and T wave (29, 11%). Children with normal ECGs had shorter epilepsy duration as compared to those with ECG abnormalities (46 [18-91] months vs. 73 [32-128 months], p = 0.004). A multivariable logistic regression model demonstrated that increasing epilepsy duration was independently associated with the presence of ECG abnormalities (OR=1.09, 95% CI=1.02-1.16, p = 0.008), adjusted for seizure frequency, generalized tonic-clonic/focal to bilateral tonic-clonic seizures as the predominant seizure type, and number of channel-modifying anti-seizure medications. Increasing epilepsy duration was also independently associated with the presence of ST/T wave abnormalities (OR=1.09, 95% CI=1.01-1.16, p = 0.017), adjusted for the same covariates.

SIGNIFICANCE

Increasing epilepsy duration is independently associated with the presence of minor ECG abnormalities. Additional studies are needed to evaluate whether this finding may represent a manifestation of the "epileptic heart".

Dual assessment of abnormal cardiac electrical dispersion and diastolic dysfunction for early detection of the epileptic heart condition

BACKGROUND

People with epilepsy (PWE) are at increased risk for premature death due to many factors. Sudden unexpected death in epilepsy (SUDEP) is among the most important causes of death in these individuals and possibly, sudden cardiac death (SCD) in epilepsy is also as important. The possibility of concurrent derangement in electrical and mechanical cardiac function, which could be a marker of early cardiac involvement in PWE, has not been investigated in that population.

METHODS

Electrical dispersion indices (T-wave peak to T-wave end, TpTe; QT dispersion, QTd; QT interval corrected for heart rate, QTc) were analyzed in patients with pharmacoresistant temporal lobe epilepsy and compared to a control group. The electromechanical relationship between those indices and echocardiographic parameters were further assessed in PWE.

RESULTS

In 19 PWE and 21 controls, we found greater TpTe and QTd in PWE (TpTe: 91.6 ± 16.4 ms vs. 65.2 ± 12.1 ms, p < 0.0001; and QTd: 45.3 ± 13.1 ms vs. 19 ± 6.2 ms, p < 0.0001, respectively). QTc was similar between PWE and controls (419.2 ± 31.4 ms vs. 435.1 ± 31.4 ms, p = 0.12). In multivariate linear regression, TpTe, QTc, and epilepsy duration were related to left ventricular mass; QTc was associated with left atrial volume; QTc, the number of seizures per month, epilepsy duration and antiseizure medication explained 81% of E/A mitral wave Doppler ratio.

CONCLUSIONS

This is the first report to demonstrate concurrent electrical dispersion and diastolic dysfunction in PWE. These noninvasive biomarkers could prove useful in early detection of the "Epileptic Heart" condition.

Nonspecific ventricular repolarization abnormalities: A wolf in sheep's clothing

The term nonspecific ventricular repolarization abnormalities refers to a set of minor alterations of the ST segment and/or the T wave. For a long time, they have been of little clinical interest as they do not translate into specific diagnoses. It has even been asserted that they constitute benign electrocardiographic findings. Their presence has been reported in various cardiovascular and non-cardiovascular diseases. However, it is frequently identified in apparently healthy asymptomatic people. A growing number of studies demonstrate their importance as predictors of cardiovascular morbidity and mortality, expanding their spectrum towards cardiovascular prevention. In light of the body of scientific evidence, it is imperative that the traditional view of nonspecific ventricular repolarization abnormalities changes.

Epilepsy duration is an independent factor for electrocardiographic changes in pediatric epilepsy

Objective

Cardiac alterations represent a potential epilepsy‐associated comorbidity. Whether cardiac changes occur as a function of epilepsy duration is not well understood. We sought to evaluate whether cardiac alterations represented a time‐dependent phenomenon in pediatric epilepsy.

Methods

We retrospectively followed pediatric epilepsy patients without preexisting cardiac conditions or ion channelopathies who had history of pediatric intensive care unit admission for convulsive seizures or status epilepticus between 4/2014 and 7/2017. All available 12‐lead electrocardiograms (ECGs) from these patients between 1/2006 and 5/2019 were included. We examined ECG studies for changes in rhythm; PR, QRS, or corrected QT intervals; QRS axis or morphology; ST segment; or T wave. Data were analyzed using multivariable models containing covariates associated with ECG changes or epilepsy duration from the univariate analyses.

Results

127 children with 323 ECGs were included in the analyses. The median epilepsy duration was 3.9 years (IQR 1.3‐8.4 years) at the time of an ECG study and a median of 2 ECGs (IQR 1‐3) per subject. The clinical encounters associated with ECGs ranged from well‐child visits to status epilepticus. We observed changes in 171 ECGs (53%), with 83 children (65%) had at least 1 ECG with alterations. In a multivariable logistic regression model adjusting for potentially confounding variables and accounting for clustering by patient, epilepsy duration was independently associated with altered ECGs for each year of epilepsy (OR: 1.1, 95% CI: 1.0‐1.2, P = .002). Extrapolating from this model, children with epilepsy durations of 10 and 15 years had 2.9 and 4.9 times the odds of having ECG changes, respectively.

Significance

Cardiac alterations may become more common with increasing epilepsy duration in select pediatric epilepsy patients. Future studies are needed to determine the potential clinical implications and the generalizability of these observations.