Treatment of end-stage peripheral artery disease by Neuromodulation

Clinical outcomes of spinal cord stimulation in patients with intractable leg pain in Japan

BACKGROUND

Neuromodulation through spinal cord stimulation (SCS) is a therapeutic option for relieving leg pain and improving the chances of limb salvage in patients with intractable chronic limb-threatening ischemia (CLTI); however, there is no consensus on its indications.

OBJECTIVE

The aim of this study was to assess the clinical outcomes of SCS in patients with intractable leg pain caused by various diseases treated in the department of cardiovascular medicine in Japan.

METHODS

This was a retrospective study of patients who underwent SCS for pain management. Patients were considered eligible for the therapy if they met the following criteria: (1) intractable leg pain (numerical rating scale [NRS] score of 10), (2) no revascularization option, and (3) no septicemia.

RESULTS

Twenty patients (mean age: 77 years; men/women: 11/9) were included in this study. The NRS score of the patients significantly reduced from 10 ± 0 before procedure to 4 ± 3 at discharge (p < 0.001). The clinical response rate of the entire cohort was 65% (13/20) at 17 ± 14 months after implantation; however, patients with intractable CLTI showed a low response rate (45%), whereas those with subacute limb ischemia showed a high response rate (100%). A multivariable regression analysis showed that hemoglobin level was significantly associated with treatment response, even after adjusting for age and sex (p = 0.026). The area under the receiver operating characteristic curve for the correlation between hemoglobin level (cutoff, 11.4 g/dL) and clinical response to SCS was 0.824 (0.619-1).

CONCLUSIONS

SCS can reduce clinical symptoms in majority of patients with intractable leg pain. Although implantation of an SCS device has been shown to improve microvascular perfusion insufficiency, the correlation between hemoglobin level and the clinical effect of SCS indicates that a preserved microcirculatory vascular bed is essential for the therapy to be effective.

Spinal Neuromodulation for Peripheral Arterial Disease of Lower Extremities: A Ten-Year Retrospective Analysis

OBJECTIVE

This long-term retrospective study evaluated the survival and amputation outcome of subjects who received neuromodulation therapy for the management of peripheral arterial disease (PAD).

MATERIALS AND METHODS

The study reviews the health data of a single cohort of 51 patients who received spinal neuromodulation (spinal cord stimulation [SCS] or dorsal root ganglion stimulation [DRG-S]) for PAD from 2007 to 2022 in a single German center. Survival rate and major amputation rate were determined. Pain, quality of life, walking distance, and opioid usage were assessed before implantation (baseline), one, six, and 12 months (M) after implantation, and then annually (during a follow-up visit). Implant-related complications also were documented.

RESULTS

In total, 51 patients (37 men [mean age 68.9 ± 10.2 years], 14 women [mean age (68.7 ± 14.6 years]) underwent SCS (n = 49) or DRG-S (n = 2) implantation owing to persistent ischemic pain. The follow-up mean years ± SD is 4.04 ± 2.73. At baseline, patients were classified as Rutherford's category 3 (n = 23), category 4 (n = 15) or category 5 (n = 9). At 24 M, 42 of 47 patients did not require a major amputation after the implant. All the patients reported nearly complete pain relief from pain at rest. A total of 75% of patients were able to walk >200 m, and 87% of patients who used opioids at baseline were off this medication at 24 M. Overall, 93% of patients reported an improvement in their overall health assessment. These improved outcomes were sustained through years three to 10 for patients who have reported outcomes.

CONCLUSIONS

Our single-center data support the efficacy of spinal neuromodulation for improvements in limb salvage, pain relief, mobility, and quality of life. The data also show that neuromodulative therapy has a long-term therapeutic effect in patients with chronic limb pain with Rutherford category 3, 4, and 5 PAD.

Improvement of brain perfusion in patients with chronic brain ischemia at epidural spinal cord electrical stimulation

Objective

Increasing life expectancy and aging of the population is accompanied by a steady increase in the number of elderly patients with chronic cerebral ischemia and age-related cognitive impairment associated with cerebral hypoperfusion and microangiopathy. The aim of this study was to identify long-term changes in cerebral blood flow (CBF) in patients with chronic cerebral ischemia at the epidural electrical stimulation of the spinal cord (SCS).

Materials and methods

Changes in cerebral blood flow were studied according to CT perfusion in 59 patients (aged 55–78 years) with vertebrogenic pain syndromes and chronic cerebral ischemia during epidural electrical stimulation of the spinal cord at the cervical (C3–C5) and lower thoracic (Th9–Th10) levels.

Results

In all patients, on the 5th day of trial SCS, an increase in cerebral blood flow by from 58.6 ± 1.13 ml/100 ml/min to 64.8 ± 1.21 ml/100 ml/min (p < 0.01) with stimulation at the Th9-Th10 level and from 58.8 ± 1.12 ml/100 ml/min to 68.2 ± 1.42 ml/100 ml/min (p < 0, 01) with stimulation at the C3-C5 level. These changes in brain perfusion were preserved during the follow-up examination 1 year after the implantation of chronic SCS system. The greatest increase in CBF was registered in the frontotemporal regions, subcortical structures and white matter of the brain. Changes in cerebral perfusion did not correlate with the degree of reduction in the severity of the accompanying pain syndrome. The change in CBF in the control group (32 patients) in all periods was not statistically significant.

Conclusion

Our results show that SCS is accompanied by a persistent improvement in brain perfusion, which may be potentially useful for developing methods for reducing age-related vascular disorders in the elderly.