Cardiac effects of repeated focal seizures in rats induced by intrahippocampal tetanus toxin: Bradyarrhythmias, tachycardias, and prolonged interictal QT interval.
Epilepsia
; 61(4): 798-809, 2020 04.
Article
en En
| MEDLINE
| ID: mdl-32201948
ABSTRACT
OBJECTIVE:
To determine electrical changes in the heart in a chronic, nonstatus model of epilepsy.METHODS:
Electrocorticography (ECoG) and electrocardiography (ECG) of nine animals (five made epileptic by intrahippocampal injection of tetanus neurotoxin (TeNT) and four controls), are monitored continuously by radiotelemetry for up to 7 weeks.RESULTS:
Epileptic animals develop a median of 168 seizures, with postictal tachycardias reaching a mean of 487 beats/min and lasting a mean of 661 seconds. Ictal changes in heart rate include tachycardia and in the case of convulsive seizures, bradyarrhythmias resembling Mobitz type 1 second-degree atrioventricular block; notably the P-R interval increased before block. Postictally, the amplitude of T wave increases. Interictally, QT dependence on RR is modest and conventional QT corrections prove ineffective. Interictal QT intervals, measured at a heart rate of 400 bpm, increased from 65 to 75 ms, an increase dependent on seizure incidence over the preceding 10-14 days.SIGNIFICANCE:
Repeated seizures induce a sustained tachycardia and increase in QT interval of the ECG and evoke arrhythmias including periods of atrioventricular block during Racine type 4 and 5 seizures. These changes in cardiac function may predispose to development in fatal arrhythmias and sudden death in humans with epilepsy.Palabras clave
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Convulsiones
/
Taquicardia
/
Bradicardia
Tipo de estudio:
Etiology_studies
Límite:
Animals
Idioma:
En
Revista:
Epilepsia
Año:
2020
Tipo del documento:
Article
País de afiliación:
Reino Unido