Vagus nerve stimulation in epilepsy during physical exercise.

Rationale:

Vagus nerve stimulation (VNS) is a form of neuromodulation as a treatment for refractory epilepsy. Besides the positive effect this stimulation can have in patients, many side effects have been reported, including dyspnea, coughing and bradycardias. Several patients also complain that they cannot get enough air when the stimulator is on while exercising.



Objective:

Primary objective: To investigate the cause of the symptoms patients with a vagus nerve stimulator experience during exercise.

Secondary objective: To investigate whether there are changes in EEG during stimulation.



Study design:

This is a case control observational study comparing epilepsy patients with a VNS that experience symptoms during exercise to those who do not experience these symptoms and epilepsy patients without a VNS.



Study population:

For this study, three groups of epilepsy patients will be included (5 patients each). The first group consists of epilepsy patients without a VNS, the second group of patients with a VNS who do not experience symptoms during exercise and the last group consists of patients with a VNS who do experience symptoms during exercise.



Intervention:

The subjects participating in this study will be measured during rest and during a non-maximal ergometry test. During these tests, which will both take approximately 20 minutes, lung function parameters, ECG, EEG, pulse oximetry and blood pressure will be measured. Epilepsy patients with a vagus nerve stimulator will be asked to activate this device to study the effect of this stimulation on the aforementioned parameters.



Main study parameters/endpoints:

The main study parameters are: lung function, ECG, EEG, blood pressure and pulse oximetry.

In patients with side effects, during VNS, there is:

1. A decrease in lung function parameters;

2. A reduced increase in heart rate;

3. A reduced increase in blood pressure.

N/A

The subjects participating in this study will be measured during rest and during a non-maximal ergometry test. During these tests, which will both take approximately 20 minutes, lung function parameters, ECG, EEG, pulse oximetry and blood pressure will be measured. Epilepsy patients with a vagus nerve stimulator will be asked to activate this device to study the effect of this stimulation on the aforementioned parameters.