Single-Center Experience With High-Density Spinal Cord Stimulation in Patients With Refractory Angina Pectoris

Objectives: Spinal cord stimulation (SCS) is a treatment option for patients with refractory angina pectoris (RAP) which was first used in 1987 and led to a reduction in the number of angina pectoris episodes, less consumption of short-acting nitrates, and an improvement in the quality of life. The conventional mode of stimulation leads to paresthesia felt at the target area. In recent years novel modes of stimulation have been developed that are paresthesia free, such as " burst, " "high-density (HD)," or " high- frequency/10 kHz" stimulation. To date, these new modes of stimulation have not been used in patients with RAP and a spinal cord stimulator. This retrospective, single-center, observational study gives a description of the experience of using HD stimulation in selected patients with RAP being treated with SCS. Materials and Methods: All patients with RAP who received a spinal cord stimulator as treatment at our center from September 2009 to February 2021 were screened. Patients were eligible for inclusion into this retrospective, observational study if 1) patients had used HD stimulation, or 2) were currently using HD stimulation. Results: Fifty-three patients out of a total of 157 patients who had a spinal cord stimulator due to RAP use or have used HD stimulation. In most patients (79.2%), the reason for switching from conventional to HD stimulation was due to progression of symptoms under conventional stimulation. The average duration of conventional stimulation use prior to switching to HD stimulation was 40.3 (+/- 29.6) months. In total, 26 patients (of 53 patients; 49.1%) were using HD stimulation at the end of the follow-up period or until lost to follow-up, and two patients used both forms of stimulation interchangeably. Five patients (9.4%) had stopped using SCS, and 20 patients (37.7%) switched back to conventional stimulation due to a variety of reasons. Conclusions: This retrospective study shows that the use of HD stimulation in patients with RAP being treated with SCS could be an alternative option for conventional stimulation. Due to the nature of this study, additional research is essential to confirm these initial findings.