Fig. 8

Sudden Death Case-1: Status-epilepticus-mediated sudden death in a 2-week-old female Kcnh2^{(+/7bp−del)} rabbit. (A). Representative EEG (black) and ECG (red) traces showing epileptiform discharges and tremors ~ 1.5 h prior to sudden death. Scale bar shown for EEG signal: 140µV amplitude, 2 s. (B1). Cardiac manifestations following a GTCS using one EEG trace, 3 referential ECG traces, and the standard bipolar and augmented ECG lead configurations (I, II, III, aVR, aVL, & aVF). Immediately following GTCS: sinus pause (~ 8 s), transient bradycardia, AV block, and inverted T-waves. Rabbit was apneic for ~ 19 s post-GTCS until first gasp (marked by arrow). Scale bar shown for ECG signal; 2000µV amplitude, 3 s. (B2). Progression of cardiac abnormalities and recovery following a convulsive seizure. Ventricular rhythm with each QRS complex and atrial rhythm with each P wave plotted over time. (C). Lethal seizure is depicted at minute zero. A cardiac tachogram is shown starting at 5 min pre-lethal seizure and ending close to asystole at 12 min post-lethal seizure. (1) Pre-ictal interval shows epileptiform activity (highlighted in green), myogenic artifact from tremors, and heart rate at ~ 300 BPM. Post-ictal intervals show (2) PGES, bradycardia (HR: ~90 BPM) and inverted T-waves, (3) PGES and atrial bigeminy, (4) PGES and 2nd degree AV block, and (5) PGES and 3rd degree AV block. Scale bars shown for EEG signal; 140µV amplitude, 2 s