Vagus nerve stimulation with tachycardia detection provides additional seizure reduction compared to traditional vagus nerve stimulation

Abstract

PurposeThis study investigates the clinical and cost effectiveness of switching from traditional vagus nerve stimulation (VNS) to responsive VNS (rVNS), which has an additional ictal tachycardia detection and stimulation (AutoStim) mode. MethodsRetrospective chart review was used to collect data from patients with medically refractory epilepsy who underwent generator replacements. Patients with confounding factors such as medication changes were excluded. Vagus nerve stimulation parameters, seizure frequency, and healthcare costs were collected for the 1-year period following generator replacement with the rVNS device. ResultsDocumented seizure frequency was available for twenty-five patients. After implant with rVNS, 28% of patients had an additional ≥50% seizure reduction. There was a significant decrease in the average monthly seizure count (p = 0.039). In patients who were not already free of disabling seizures (n = 17), 41.2% had ≥50% additional seizure reduction. There was no difference in healthcare costs during the 1-year follow-up after the rVNS implant compared with one year prior. ConclusionsIctal tachycardia detection and stimulation provided a significant clinical benefit in patients who were not free of disabling seizures with treatment from traditional VNS. There was no additional increase in healthcare costs during the first year after device replacement.