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.
- Klíčová slova
- QT correction, QT prolongation, cardiac dysfunction, epilepsy,
- MeSH
- bradykardie etiologie MeSH
- elektrokardiografie MeSH
- elektrokortikografie MeSH
- krysa rodu Rattus MeSH
- náhlá neočekávaná smrt při epilepsii etiologie MeSH
- neurotoxiny toxicita MeSH
- potkani Wistar MeSH
- tachykardie etiologie MeSH
- tetanový toxin toxicita MeSH
- záchvaty chemicky indukované komplikace patofyziologie MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- neurotoxiny MeSH
- tetanový toxin MeSH
