Does the type of seizure influence heart rate variability changes?

Maria Teresa Faria; Susana Rodrigues; Manuel Campelo; Duarte Dias; Ricardo Rego; Helena Rocha; Francisca Sá; Marta Tavares-Silva; Roberto Pinto; Gonçalo Pestana; Ana Oliveira; Jorge Pereira; João Paulo Silva Cunha; Francisco Rocha-Gonçalves; Hernâni Gonçalves; Elisabete Martins

doi:10.1016/j.yebeh.2021.108453

Does the type of seizure influence heart rate variability changes?

Epilepsy Behav. 2022 Jan:126:108453. doi: 10.1016/j.yebeh.2021.108453. Epub 2021 Dec 1.

Authors

Maria Teresa Faria¹, Susana Rodrigues², Manuel Campelo³, Duarte Dias², Ricardo Rego⁴, Helena Rocha⁴, Francisca Sá⁴, Marta Tavares-Silva⁵, Roberto Pinto⁶, Gonçalo Pestana⁶, Ana Oliveira⁷, Jorge Pereira⁷, João Paulo Silva Cunha⁸, Francisco Rocha-Gonçalves⁹, Hernâni Gonçalves¹⁰, Elisabete Martins³

Affiliations

¹ Nuclear Medicine Department, Centro Hospitalar Universitário de São João, E.P.E., Porto, Portugal. Electronic address: mteresafaria@gmail.com.
² Institute for Systems Engineering and Computers Technology and Science (INESC TEC), Porto, Portugal.
³ Cardiology Department, Centro Hospitalar Universitário de São João, E.P.E., Porto, Portugal; Department of Medicine, Faculty of Medicine, University of Porto, Porto, Portugal.
⁴ Neurophysiology Unit, Neurology Department, Centro Hospitalar Universitário de São João, E.P.E., Porto, Portugal.
⁵ Cardiology Department, Centro Hospitalar Universitário de São João, E.P.E., Porto, Portugal; Department of Surgery and Physiology, Cardiovascular R&D Centre, Faculty of Medicine, University of Porto, Porto, Portugal.
⁶ Cardiology Department, Centro Hospitalar Universitário de São João, E.P.E., Porto, Portugal.
⁷ Nuclear Medicine Department, Centro Hospitalar Universitário de São João, E.P.E., Porto, Portugal.
⁸ Institute for Systems Engineering and Computers Technology and Science (INESC TEC), Porto, Portugal; Faculty of Engineering, University of Porto, Porto, Portugal.
⁹ Department of Medicine, Faculty of Medicine, University of Porto, Porto, Portugal.
¹⁰ Department of Community Medicine, Information and Health Decision Sciences, Faculty of Medicine, University of Porto, Porto, Portugal; CINTESIS, Faculty of Medicine, University of Porto, Portugal.

PMID: 34864377
DOI: 10.1016/j.yebeh.2021.108453

Abstract

Objective: Heart rate variability (HRV), an index of the autonomic cardiac activity, is decreased in patients with epilepsy, and a low HRV is associated with a higher risk of sudden death. Generalized tonic-clonic seizures are one of the most consistent risk factors for SUDEP, but the influence (and relative risk) of each type of seizure on cardiac function is still unknown. Our objective was to assess the impact of the type of seizure (focal to bilateral tonic-clonic seizure - FBTCS - versus non-FBTCS) on periictal HRV, in a group of patients with refractory epilepsy and both types of seizures.

Methods: We performed a 48-hour Holter recording on 121 patients consecutively admitted to our Epilepsy Monitoring Unit. We only included patients with both FBTCS and non-FBTCS on the Holter recording and selected the first seizure of each type to analyze. To evaluate HRV parameters (AVNN, SDNN, RMSSD, pNN20, LF, HF, and LF/HF), we chose 5-min epochs pre- and postictally.

Results: We included 14 patients, with a median age of 36 (min-max, 16-55) years and 64% were female. Thirty-six percent had cardiovascular risk factors, but no previously known cardiac disease. In the preictal period, there were no statistically significant differences in HRV parameters, between FBTCS and non-FBTCS. In the postictal period, AVNN, RMSSD, pNN20, LF, and HF were significantly lower, and LF/HF and HR were significantly higher in FBTCS. From preictal to postictal periods, FBTCS elicited a statistically significant rise in HR and LF/HF, and a statistically significant fall in AVNN, RMSSD, pNN20, and HF. Non-FBTCS only caused statistically significant changes in HR (decrease) and AVNN (increase).

Significance/conclusion: This work emphasizes the greater effect of FBTCS in autonomic cardiac function in patients with refractory epilepsy, compared to other types of seizures, with a significant reduction in vagal tonus, which may be associated with an increased risk of SUDEP.

Keywords: Focal to bilateral tonic-clonic seizures; Generalized tonic-clonic seizures; Heart rate variability; Refractory epilepsy; SUDEP.

MeSH terms

Adolescent
Adult
Electroencephalography
Epilepsy* / physiopathology
Female
Heart Rate* / physiology
Humans
Male
Middle Aged
Risk Assessment
Seizures* / classification
Seizures* / physiopathology
Sudden Unexpected Death in Epilepsy / epidemiology
Young Adult