Neuromodulation of Inflammation and Vascular Function in Systolic Heart Failure

University of Oklahoma7 enrolled

Overview

Heart failure (HF) is the leading cause of death in US. It is associated with abnormal vascular function termed endothelial dysfunction. It is also associated with increased stress on the blood vessels and high levels of inflammation. Vagus nerve stimulation can help improve inflammation, vascular function and vascular stress. The investigator has recently completed a study showing that 1 hour of noninvasive vagus stimulation can improve vascular health. However, it is unknown if 4 weeks of stimulation will be beneficial in systolic heart failure. The purpose of this study is to determine if transcutaneous vagal stimulation (TVS) will lead to improvement in the function of the inner lining of participants' arteries, memory, and in the levels of certain chemical markers of arterial function in the blood. Participants will be randomized to receive either TVS or a sham stimulation and undergo 4 weeks of stimulation. Vascular function will be assessed by several non-invasive measurements, including Flow Mediate Dilation (FMD), Pulse Wave Analysis (PWA), EndoPAT, and Laser Speckle Contrast Imaging (LSCI). Participants' memory will also be measured through electronic assessments and blood will be collected and analyzed for arterial function chemical markers.

Visit 1: Following tests(to assess vascular function) will be done: 1. FMD 2) LSCI 3) EndoPAT and 4) Pulse wave analysis (PWA). Patients will rest for 10 minutes between each test. They will be trained to use PARASYMTM unit for TVS. Blood collected, serum/plasma will be stored at -80F. Whole blood will be collected in PAXgene tubes. Patients will be instructed to apply TVS to either ear lobule (SHAM) or Tragus(experimental arm). Baseline characteristics will be collected including data on ventricular function(LVEF and left ventricular volumes). Visit 2 (4 weeks): Follow up tests(FMD,LSCI,EndoPAT,PWA) and repeat blood collection. Inflammatory cytokines and vascular function assays will be performed.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

Eligibility

Sex: ALLMin age: 18 YearsMax age: 85 Years

Medical Language ↔ Plain English

Inclusion Criteria: 1\. Patients (18 years or older) with Heart failure with reduced ejection fraction (HFrEF), which is a history of symptomatic heart failure with left ventricular ejection fraction (LVEF) of \< 40%. Exclusion Criteria: 1. Patients in overt congestive heart failure / recent acute myocardial infarction (\< 3 months) or Unstable angina 2. Active malignancy 3. Pre-menopausal women and post-menopausal women on hormone supplements. 4. Unilateral or bilateral vagotomy 5. Patients with bilateral upper extremity amputation 6. Pregnant patients 7. End-stage renal disease 8. End-stage liver disease 9. History of recurrent vasovagal syncope, Sick sinus syndrome, 2nd- or 3rd-degree atrioventricular (AV) block. 10. Patients with clinically documented upper extremity arterial disease 11. Patients with a body mass index (BMI) \>35 12. Significant hypotension (blood pressure \<90mmHg) secondary to autonomic dysfunction

Outcomes

Primary Outcomes

Flow Mediated Dilation (FMD)

FMD is a change in the maximal diameter of the brachial artery. Brachial artery diameter (in millimeters) will be assessed before and after 4 weeks of stimulation using standard ultrasound.

Time frame: Change in the brachial artery diameter will be compared to baseline change after 4 weeks of TVS or sham.

Laser Speckle Contrast Imaging (LSCI)

LSCI based perfusion index and perfusion units will be calculated before and after 4 weeks of TVS or sham stimulation.

Time frame: Change in the perfusion units will be determined at baseline and after 4 weeks of TVS or sham stimulation.

EndoPAT

Hyperemia index measured with ENDOPAT will be calculated before and after 4 weeks of TVS. Hyperemia index will be calculated using the standard ENDOPAT technique using probes placed on bilateral finger.

Time frame: Change in the reactive hyperemia index from baseline and after 4 weeks of TVS or SHAM stimulation

Pulse Wave Analysis (PWA)

Arterial elasticity. Augmentation pressure (AP) will be calculated which is expressed as a percentage of the aortic pulse pressure (PP) which is the difference of systolic and diastolic BP(mm Hg).

Time frame: Change in the augmentation index will be calculated at baseline and after 4 weeks of TVS or sham stimulation.

Biomarkers of inflammation

Inflammatory cytokines will assayed at baseline and after 4 weeks of stimulation. Cytokines assayed : Il1B,IL-6,IL-17,TNF-a,TGF-b,CRP etc- expressed in pg/ml units).

Time frame: Change in these biomarkers(% change) over 4 weeks will be calculated.

Biomarkers of endothelial function and oxidative stress

Biomarkers of endothelial function and oxidative stress include: ORAC, HORAC scores expressed as %.

Time frame: Change in these biomarkers(%) over 4 weeks will be calculated.

Secondary Outcomes

Cognition

Cognition score(%) calculated from Cambridge Neuropsychological Test Automated Battery -CANTAB method . This will be done using a hand held ipad.

Time frame: Change in the cognition score , as assessed by the CANTAB method will be compared at baseline and after 4 weeks of TVS or sham stimulation.

Neuromodulation of Inflammation and Vascular Function in Systolic Heart Failure

Overview

Conditions

Interventions

Eligibility

Locations (1)

Outcomes

Primary Outcomes

Secondary Outcomes