Replacement of traditional vagus nerve stimulation with cardiac-based device and seizure reduction: A systematic review and meta-analysis

Author: Jordana Borges C Diniz1, Francisco Alfonso Rodriguez Elvir2, Laís Silva Santana3, Sávio Batista4, Luisa Glioche Gasparri5, João Paulo Mota Telles6, Allan Dias Polverini7
1 Goiania Neurological Institute, Goiania, Brazil.
2 Santa Casa de Misericordia de Porto Alegre, Brazil.
3 School of Medicine, University of São Paulo, Sao Paulo, Brazil.
4 Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
5 University Estacio de Sá, Faculty of Medicine, Rio de Janeiro, Brazil.
6 Department of Neurology, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, Brazil. Electronic address:
7 Neurosurgical Oncology Division, Hospital de Amor, Fundação Pio XII, Barretos, Brazil.
Conference/Journal: Seizure
Date published: 2024 Apr 6
Other: Volume ID: 118 , Pages: 65-70 , Special Notes: doi: 10.1016/j.seizure.2024.04.001. , Word Count: 235

For patients with drug-resistant epilepsy (DRE) who are not suitable for surgical resection, neuromodulation with vagus nerve stimulation (VNS) is an established approach. However, there is limited evidence of seizure reduction when replacing traditional VNS (tVNS) device with a cardiac-based one (cbVNS). This meta-analysis compares the seizure reduction achieved by replacing tVNS with cbVNS in a population with DRE.

We systematically searched PubMed, Embase, and Cochrane Central following PRISMA guidelines. The main outcomes were number of patients experiencing a ≥ 50 % and ≥80 % reduction in seizures, as defined by the McHugh scale. Additionally, we assessed the number of patients achieving freedom from seizures.

We included 178 patients with DRE from 7 studies who were initially treated with tVNS and subsequently had it replaced by cbVNS. The follow-up for cbVNS ranged from 6 to 37.5 months. There was a statistically significant reduction in seizure frequency with the replacement of tVNS by cbVNS, using a ≥ 50 % (OR 1.79; 95 % CI 1.07 to 2.97; I²=0 %; p = 0.03) and a ≥ 80 % (OR 2.06; 95 % CI 1.17 to 3.62; I²=0 %; p = 0.01) reduction threshold. Nineteen (13 %) participants achieved freedom from seizures after switching to cbVNS. There was no difference in the rate of freedom from seizures between groups (OR 1.85; 95 % CI 0.81 to 4.21; I²=0 %; p = 0.14).

In patients with DRE undergoing battery replacement, cbVNS might be associated with seizure reduction (≥50 % and ≥80 % threshold) after switching from tVNS. Randomised controlled trials are necessary to validate these findings.

Keywords: Cardiac-based stimulation; Closed-loop stimulation; Drug-resistant epilepsy; Vagus nerve stimulation.

PMID: 38642446 DOI: 10.1016/j.seizure.2024.04.001