This extension study, designed as a long-term follow up, will monitor the course of the disease and its treatment safety and efficacy by collecting the appropriate data and using data collected under the long term provisions of the DEBuT-HT study to describe and analyze the changes in ongoing drug treatment, the programming parameters of the implanted active device and any occurring adverse events over a period of up to 13 months after implant surgery in the DEBuT-HT trial. Annual follow-ups of up to five years are planned subsequently to the 13-month follow-up period.
