Effectiveness of vagus nerve stimulation in Dravet syndrome: a case series.

PURPOSE

The purpose of this study is to report seizure outcomes for patients with Dravet syndrome (DS) who underwent vagus nerve stimulator (VNS) implantation at our center.

METHODS

We conducted a retrospective review of patients with DS who underwent VNS implant at UPMC Children's Hospital of Pittsburgh from 2005 to 2024 with at least 1 year of follow-up. Demographics and medical history related to epilepsy were collected at baseline. The primary outcome was response to VNS at 1 and 2 years post-VNS, defined as ≥ 50% reduction in seizure frequency compared to baseline. The number of anti-seizure medications (ASMs) and diet modification were also collected at 1 and 2 years post-VNS.

RESULTS

A total of 13 patients (69.2% female) with DS underwent VNS at a median age of 4.17 years (IQR, 2.58-4.58) and presented for follow-up at 1 (n = 13) and 2 (n = 9) years post-VNS. The response rate in our cohort was 61.5% (n = 8) at 1 year and 55.6% (n = 5) at 2 years post-VNS. Reduction in the number of ASMs was reported in a total of 7 (53.8%) patients, 4 of whom had reached the 2-year follow-up. Diet modification was attempted as a treatment strategy in 3 (23.1%) patients prior to VNS and maintained through 2 years post-VNS in 1 patient.

CONCLUSIONS

VNS is associated with > 50% seizure frequency reduction in approximately 50% of patients with DS and may play a role in the multimodal treatment strategy employed for seizure control in these patients.