Right-versus-left SOZ heart-rate differences were inconclusive in 27 HUP SEEG patients

We tested whether ictal tachycardia is larger when the seizure-onset zone (SOZ) is in the right hemisphere. A pre-registered plan was written before SOZ labels were read and before new ECG data were fetched. We analyzed the first seizure in 27 HUP SEEG patients, combining archived heart-rate (HR) series with 10 additional patients processed using unchanged code. SOZ side was assigned from clinician channel labels and channel-name prefixes. Of 33 seizures with HR data, 30 passed the quality rule; 12 had right SOZ and 15 left SOZ. In the 30-60 s after onset, mean HR increase was +32.1 bpm for right SOZ and +20.2 bpm for left SOZ: difference +11.9 bpm (95% bootstrap CI -8.3 to +30.9; permutation p = 0.26; Holm p = 0.53). In the 0-30 s window the difference was +1.6 bpm (p = 0.85; Holm p = 0.85). By the pre-registered rule, the result is inconclusive because the primary confidence interval includes +20 bpm; a large right-over-left effect is not excluded, while a difference larger than about +31 bpm is not compatible with these data. Both sides showed tachycardia. In the nine new patients passing quality, the 30-60 s increase was +9.0 bpm (7/9 positive; exact sign-flip p = 0.16), smaller than in the 21 archived patients (+32.9 bpm). Limits include one seizure per patient, low power, SOZ classification from channel labels and channel-name prefixes, unequal SEEG sampling between hemispheres, and no seizure-type, sleep-state, or medication data. SOZ side does not establish the side of seizure spread at 30-60 s.

ictal tachycardia · heart rate · seizure-onset zone · SEEG · epilepsy · laterality · OpenNeuro ds004100