• Seizure disorder are frequent paediatric age group problem.
• They are result of abnormal neuronal activity.
• Most of them are controlled with anti-epileptic.
• However, a few mimics of seizure are easy to miss and potentially fatal.

Seizure disorder

• 3yr girl
• Recurrent episodes up rolling of eyeballs with loss of consciousness
• Short lasting episodes with spontaneous recovery
• A few times tonic posturing
• Precipitated by excitement, physical activity
• Poorly controlled on various medications with appropriate dosage single and combination : valproic acid, carbamazepin, levetiracetam etc
• EEG: no abnormal activity
• CT brain: with in normal limits
• BERA: e/o hearing impairment

ECG

Therapy for Long QT

• Patient was started on Propranolol 1mg/kg/dose BID
• There was no recurrence of episodes on medication.
• Other options include cervical sympathectomy, AICD, pacemaker etc.

How can long QT present at seizure?

• Patients with long QT have runs as polymorphic ventricular tachycardia.
• During VT, heart is not able to pump blood and leads to cerebral anoxia.
• This can manifest as seizure or syncope.
• As VT terminates spontaneously or with therapy, circulation is restored and consciousness is regained.

What is the risk with polymorphic VT?

• Any episode of polymorphic VT can degenerate into ventricular fibrillation and lead to cardiac arrest and sudden death.
• Long QT has prevalence of 1 per 2000to 4000.
• Rare disease. Many varieties.
• Sudden death and syncope are common presentation

Factors suggesting alternate etiology for seizure in this case

• EEG: Normal
• Poorly controlled episodes on medication
• Brain imaging normal
• Hearing loss ( associated with Long QT)

Take home message

• Rule out alternate cause of seizure in case of abnormal presentation.
• 12 lead ECG and QTc reported by a cardiologist is strongly recommended.
• Long QT is potentially fatal condition
• Prevention of VT with medication is the treatment.
• Beta blockers are effective therapy.

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