Spinal Cord Stimulation for Orthostatic Hypotension

Study Overview
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Brief Summary
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This is a prospective single-center randomized crossover control study that aims to evaluate the effects of non-invasive transcutaneous spinal cord stimulation in patients with known or suspected orthostatic hypotension.

Detailed Description
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The hypothesis is that transcutaneous spinal cord stimulation at thoracic level may correct hypotensive episodes during tilt testing in subjects with blood pressure drops. Eligible patients will sign an informed consent form before the procedure. Non-invasive transcutaneous electrical stimulation of the spinal cord will be applied using modulated electrical impulses through external adhesive electrode patches connected to a neural stimulator device. The study protocol includes analysis of the following parameters: heart rate; 12-lead electrocardiogram; continuous beat-to-beat blood pressure recordings (measured noninvasively by plethysmography) before stimulation, during stimulation and after spinal cord stimulation. All registered data will be analyzed at the end of the procedure.

Official Title
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Hemodynamic Effects of Transcutaneous Spinal Cord Stimulation During Passive Orthostasis: a Prospective Single-center Randomized Cross-over Study

Conditions
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Orthostatic Hypotension

Intervention / Treatment
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* Procedure: Spinal cord stimulation
* Procedure: Sham stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18-85 years Suspected orthostatic hypotension (having a history of syncope and/or pre-syncope that occurred during the transition to an upright position, with complaints of recurrent dizziness that occurs during the transition to an upright position) or documented orthostatic hypotension. The patient who signed the informed consent form Exclusion Criteria: Orthostatic hypotension caused by acute hypovolemia or bleeding. Chronic heart failure III-IV functional class (NYHA) Structural heart disease of the following: hypertrophic cardiomyopathy with obstruction of the left ventricular outflow tract, acute coronary syndrome, restrictive cardiomyopathy, hemodynamically significant valvular heart defects, uncorrected hemodynamically significant congenital heart defects. Ongoing acute illness. >90% paced cardiac rhythm. Permanent atrial fibrillation. A history of transient ischemic attack or stroke within 3 months before the enrollment and/or incomplete recovery. Pulmonary embolism <1 month ago. Epilepsy. The presence of an implantable pump. Patients with contraindications to the use of the patch electrodes used in this study, as indicated in the relevant instructions for use.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Patients will undergo spinal cord stimulation or a sham procedure during tilt testing following randomization. Then a second test will be performed the same day after crossover. A repeated test will be performed after 7 days in reverse order (sham or stimulation).
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Spinal cord stimulation<br>Before tilt testing, adhesive patches are applied to subjects' back skin. Single stimuli are delivered to the patches in order to define the stimulation threshold under the guidance of neuromyography. An investigator says loudly: I am initiating high-frequency stimulation. Stimulation is initiated within 2 min before tilting the table. Then verticalization of the table 45 degrees is performed, and the test is continued for 15-30 min. Beat-to-beat blood pressure recording is carried out and 10 min after blood pressure complete stabilization the test is ended. | Procedure: Spinal cord stimulation<br>* Single stimuli are delivered to define the stimulation threshold. High-frequency stimulation with modulated current via skin patches captures posterior horns of the spinal cord.<br>|
| Sham Comparator: Sham stimulation<br>Before tilt testing, adhesive patches are applied to subjects' back skin. Single stimuli are delivered to the patches in order to define stimulation threshold under the guidance of neuromyography. An investigator says loudly: I am initiating high-frequency stimulation. No stimulation is initiated. Two minutes after, verticalization of the table 45 degrees is performed, and the test is continued for 15-30 min. Beat-to-beat blood pressure recording is carried out and 10 min after blood pressure complete stabilization the test is ended. | Procedure: Sham stimulation<br>* Single stimuli are delivered to define the stimulation threshold. High-frequency stimulation is not delivered.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Systolic blood pressure drop correction | It is suggested that spinal cord stimulation will correct systolic blood pressure drop during tilt testing. The effect is expected within 5-10 mmHg as a difference between minimum systolic blood pressure during stimulation and without stimulation (sham). | 5-30 minutes following verticalization | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Diastolic blood pressure drop correction | It is suggested that spinal cord stimulation will correct diastolic blood pressure drop during tilt testing. The effect is expected within 5-10 mmHg as a difference between minimum diastolic blood pressure during stimulation and without stimulation (sham). | 5-30 minutes following verticalization | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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spinal cord stimulation, hypotension, hemodynamic effects