Abnormal ECG, Seizures, and Associated Neurological Deficits

In the early 1980s, a 17-year-old girl and her mother were referred to me. The mother had a life-long history of seizures—ultimately well controlled with phenytoin—but she had never had an ECG. Her daughter began to have seizures in late childhood, several times per year, 1 of which was particularly prolonged and left her with a new, permanent neurological disorder impairing motor skills, comprehension, and memory. Two years before the referral, the daughter had an ECG, after which her seizure medications were changed to phenytoin. The ECG is shown in Figure 1. What abnormalities are present and how, if at all, might they relate to the seizures? Would you continue to treat her with phenytoin, or would you change to another agent, and if so, which? …