Spinal Cord Stimulation Manages Low Blood Pressure After Spinal Cord Injury: Hemon Study Updates

Introduction: Spinal cord injury (SCI) disrupts autonomic pathways that regulate blood pressure (BP). Consequently, 78% of individuals with tetraplegia experience orthostatic hypotension (OH), which negatively impacts health and quality of life. Still, only 28% receive treatment, and 91% of those treated with existing management options remain symptomatic. Early clinical feasibility study results showed ARC-IM Therapy, investigational targeted epidural spinal cord stimulation, manages OH through precise modulation of the hemodynamic hotspot located in the lower thoracic spinal cord. Ongoing clinical feasibility studies aim to further establish the safety and effectiveness of ARC-IM Therapy in individuals with SCI across two independent sites: a research center in Switzerland (HemON, NCT05111093) and a clinical rehabilitation center in the Netherlands (HemON-NL, NCT05941819).

Methods: Twelve individuals with SCI above T6 and confirmed OH received an epidural paddle lead positioned over the lower thoracic spinal cord and an implantable pulse generator to deliver ARC-IM Therapy. Stimulation programmed to improve BP has been used during in-clinic rehabilitation sessions and at home for up to 2 years post-implantation. Efficacy outcomes include seated BP measures with and without stimulation and changes from baseline at post-implantation timepoints in the Autonomic Dysfunction Following Spinal Cord Injury (ADFSCI) hypotension domain, the Medical Outcomes Study (MOS) Sleep Somnolence subscore, and the Canadian Occupational Performance Measure (COPM). Changes in subjective outcomes are presented as mean±standard error. Safety outcomes include the number of serious device-related adverse events.

Results: Immediate and significant increases in seated BP towards healthy values were achieved with ARC-IM Therapy compared to without stimulation (group mean systolic/diastolic = 98.8/62.6 vs. 88.9/53.6 mmHg, p< 0.025). Hypotension symptom burden decreased significantly by three months post-implantation and remained significantly reduced at the six-month follow-up (ADFSCI Month 3 Δ=-21.1±8.0, p=0.025; Month 6 Δ=-19.3±7.7, p=0.023). Fatigue, a common hypotension symptom, also significantly improved by the three-month follow-up (MOS Sleep Somnolence Δ=-14.2±5.4, p=0.041). Participants reported greater performance and satisfaction with occupational tasks at one- and six-months post-implantation (COPM Month 1 performance Δ=2.2±0.5, satisfaction Δ=2.3±0.5; Month 6 performance Δ=1.7±0.5, satisfaction Δ=2.1±0.4; all p≤0.003). No serious device-related adverse events or serious post-surgical complications have occurred in either study.

Conclusion: ARC-IM Therapy can safely and effectively manage symptomatic OH following SCI. The successful implementation in both a research-focused institution and a standard rehabilitation clinic marks a key step toward wider availability for the SCI community. The results indicate a significant impact on quality of life and support the upcoming EMPOWER BP pivotal trial.