Lead Sponsor

University of Oklahoma

Age

18 - 85 years

Sex

ALL

Healthy Volunteers

No

•1. peripheral arterial disease (PAD) - patients with an ankle-brachial index of \<0.9
•2. symptoms of intermittent claudication, rest pain, or minor tissue loss (Rutherford category I-V)

•1. patients with acute limb ischemia
•2. Patients with overt congestive heart failure / recent acute myocardial infarction (\< 3 months)
•3. Premenopausal women and post-menopausal women on hormone supplements.
•4. chronic inflammatory disease (systemic lupus erythematosus, rheumatoid arthritis, and Crohn's disease), or receiving therapy with steroids, cyclosporine, methotrexate or immunocompromised patients.
•5. unilateral or bilateral vagotomy
•6. Patients with bilateral upper extremity amputation
•7. pregnant patients
•8. prisoners
•9. end-stage renal disease.
•10. End-stage liver disease.
•11. patients with BMI\>34
•12. Patients with upper extremity arterial disease
•13. history of recurrent vasovagal syncope, Sick sinus syndrome, 2nd- or 3rd-degree atrioventricular block (AV) block, prolonged first degree AV block.
•14. Refusal to sign a consent form.
•15. Significant hypotension from autonomic dysfunction
•16. Patients with pacemakers who have significant interaction with TVNS during testing