Transauricular Vagal Nerve Stimulation; Functional Dyspepsia and Gastroparesis (AVNS)

Effects of Transauricular Vagal Nerve Stimulation on Electrogastrography (EGG) and Heart Rate Variability (HRV) in Healthy Subjects, Functional Dyspepsia, and Gastroparesis

The goal of this study is to establish parameters of gastric myoelectrical activity and heart rate variability in healthy human subjects and compare and contrast them to those with gastroparesis and functional dyspepsia, at baseline and following taVNS.

Study Overview

• Status: Withdrawn
• Conditions: Healthy; Functional Dyspepsia; Gastroparesis; Digestive System Disease; Gastroenterology
• Intervention / Treatment: Device: Transauricular Vagal Nerve Stimulation

Detailed Description

This is a prospective pilot study assessing the relationship of electrogastrography and heart rate variability, with transauricular stimulation of the vagal nerve in healthy subjects compared to gastroparesis and functional dyspepsia patients. The investigators plan to recruit a total of 60 patients: 20 healthy volunteers, 20 gastroparesis, and 20 functional dyspepsia patients. Participants will undergo two testing sessions in which electrogastrography (EGG) and heart rate variability (HRV) will be measured using electrodes following transauricular vagal nerve stimulation (tAVNS) at various frequencies.

• Study Type: Interventional
• Phase: Not Applicable

Contacts and Locations

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 85 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Male or female.
2. Age 18-85 years.
3. Healthy volunteer or established diagnosis of idiopathic, diabetic, or postsurgical gastroparesis and functional dyspepsia.
4. Patient is capable of giving informed consent.
5. Patient is on stable doses of other medications for gastroparesis or functional dyspepsia for preceding 4 weeks prior to enrollment (including cholinergics, anti-cholinergics, dopamine and serotonin receptor agonists/antagonists, motility agents, neuromodulators, herbals).

Exclusion Criteria:

1. Any diagnosis of systemic autonomic dysfunction.
2. Use of narcotic, anticholinergic, cholinergic, or promotility medications in preceding 2 weeks of study.
3. Enteric feeding tubes.
4. Parenteral nutrition.
5. Severe disease flare requiring hospitalization or ER visits within 3 months of study.
6. Untreated depression or suicidal thoughts.
7. Pregnant/breastfeeding women.
8. History of gastric pacemaker implantation.
9. Implantable electronic devices (i.e. cardiac pacemakers)
10. Extrinsic myopathy/neuropathy
11. Vagal nerve injury.
12. High risk cardiac arrhythmias (high grade AV block, atrial fibrillation, atrial flutter).
13. GERD.
14. History of dumping syndrome.
15. History of rapid gastric emptying.
16. Severe allergy to skin adhesives.
17. Concurrent enrollment in other clinical trials.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Gastroparesis; Patients diagnosed with Gastroparesis.	Device: Transauricular Vagal Nerve Stimulation; TENS 7000 is a handheld device used to deliver electrical impulses for nerve stimulation to help modulate and treat chronic pain. The manufacturer, Roscoe, has regulatory approval for the use of nerve stimulator therapy in the acute and/or prophylactic treatment of headaches, migraines, sciatica, muscle spasms, acute and chronic pain, and improve circulation. It is FDA approved in the USA for the above indications, but has not been approved for use in gastrointestinal diseases such as gastroparesis or functional dyspepsia. It has been registered as an investigational new device in various clinical trials. The purpose of this protocol is to provide vagal nerve stimulation to patients with gastroparesis, functional dyspepsia, and healthy controls as a comparison.; Other Names: vagal nerve stimulation
Experimental: Functional Dsypepsia; Patients diagnosed with Functional Dsypepsia.	Device: Transauricular Vagal Nerve Stimulation; TENS 7000 is a handheld device used to deliver electrical impulses for nerve stimulation to help modulate and treat chronic pain. The manufacturer, Roscoe, has regulatory approval for the use of nerve stimulator therapy in the acute and/or prophylactic treatment of headaches, migraines, sciatica, muscle spasms, acute and chronic pain, and improve circulation. It is FDA approved in the USA for the above indications, but has not been approved for use in gastrointestinal diseases such as gastroparesis or functional dyspepsia. It has been registered as an investigational new device in various clinical trials. The purpose of this protocol is to provide vagal nerve stimulation to patients with gastroparesis, functional dyspepsia, and healthy controls as a comparison.; Other Names: vagal nerve stimulation
Experimental: Healthy Controls; Healthy volunteers (without Functional Dsypepsia or Gastroparesis)	Device: Transauricular Vagal Nerve Stimulation; TENS 7000 is a handheld device used to deliver electrical impulses for nerve stimulation to help modulate and treat chronic pain. The manufacturer, Roscoe, has regulatory approval for the use of nerve stimulator therapy in the acute and/or prophylactic treatment of headaches, migraines, sciatica, muscle spasms, acute and chronic pain, and improve circulation. It is FDA approved in the USA for the above indications, but has not been approved for use in gastrointestinal diseases such as gastroparesis or functional dyspepsia. It has been registered as an investigational new device in various clinical trials. The purpose of this protocol is to provide vagal nerve stimulation to patients with gastroparesis, functional dyspepsia, and healthy controls as a comparison.; Other Names: vagal nerve stimulation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Establish EGG/HRV parameters and effects following taVNS	The first primary outcome measure will be to establish measures of EGG and HRV parameters in healthy volunteers and determine effects of tAVNS on EGG and HRV. The HRV parameters to be measured will include mean heart rate (HR), standard deviation of HR, mean respiratory rate (RR) interval, standard deviation of RR interval, low/high frequency (LF, HF, LF/HF), normalized LF, and normalized HF. The EGG parameters to be measured will be of gastric slow wave power, gastric slow wave propagation, and phase gradient directionality.	3-5 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Determine deviations in EGG/HRV parameters and effects following taVNS	To determine if gastroparesis or functional dyspepsia patients have significant deviations in EGG (slow wave power, propagation, and phase gradient directionality) and HRV (mean HR, LF, HF, mean RR) parameters at baseline and following tAVNS compared to healthy volunteers.	3-5 years

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Determine Stimulation Parameters of tAVNS with Greater Effect on Gastroparesis and Functional Dyspepsia	To determine what stimulation parameters have a greater effect on EGG variables (gastric slow wave power, propagation, and phase gradient directionality,) and HRV variables (mean HR, mean RR, LF, HF) in gastroparesis and functional dyspepsia patients.	3-5 years

Collaborators and Investigators

• Sponsor: Stanford University
• Investigators: Study Director: Wendy XY Zhou, DO, Fellow; Principal Investigator: Sandya Subramanian, Phd, Postdoctoral Fellow; Principal Investigator: Todd Coleman, Phd, Associate professor; Principal Investigator: Linda Nguyen, MD, Clinical Professor of Medicine

Study record dates

Study Major Dates

• Study Start (Estimated): January 1, 2024
• Primary Completion (Estimated): January 1, 2025
• Study Completion (Estimated): September 1, 2025

Study Registration Dates

• First Submitted: May 23, 2022
• First Submitted That Met QC Criteria: June 1, 2022
• First Posted (Actual): June 6, 2022

Study Record Updates

• Last Update Posted (Actual): August 3, 2025
• Last Update Submitted That Met QC Criteria: July 30, 2025
• Last Verified: July 1, 2025

More Information

Terms related to this study

• Keywords: functional dyspepsia; gastroparesis; vagal nerve stimulation; digestive; gastroenterology; auricular; EGG; stanford
• Additional Relevant MeSH Terms: Neurologic Manifestations; Signs and Symptoms, Digestive; Stomach Diseases; Paralysis; Gastrointestinal Diseases; Digestive System Diseases; Dyspepsia; Gastroparesis
• Other Study ID Numbers: 63421

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes