Cardiac arrhythmias mimicking primary neurological disorders: a difficult diagnostic situation.

Cardiac arrhythmias can present with the signs and symptoms of a seizure disorder. This potentially life-threatening underlying cause of non-febrile seizures should be recognized early, since successful specific treatment is possible. The purpose of this retrospective study was to examine common features in such patients. Over a period of 25 years, eight patients were initially treated for up to 5 years at our institution for a seizure disorder until dysrhythmia as the underlying cause of the seizures was disclosed. The main symptom was drop attacks coinciding with physical activity or emotional stress. Convulsions were only rarely observed. In five of the eight patients the underlying disorder was the long-QT-syndrome (Romano-Ward syndrome). In one patient intermittent complete atrioventricular block was found, another patient showed ventricular tachydysrhythmia of unknown etiology and the last patient suffered from hypertrophic cardiomyopathy.