External Body Pressure in Heart Failure With Preserved Ejection Fraction

Study Overview
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Brief Summary
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The primary objective of the study is to test the impact of positive and negative body pressure on exercise capacity, symptoms, blood volume distribution and central cardiac hemodynamics in patients with heart failure and preserved ejection fraction. Aim 1 will study healthy volunteers and heart failure patients non invasively while Aim 2 will study heart failure patients invasively (intracardiac pressures).

Official Title
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External Body Pressure and the Impact on Exercise in Heart Failure With Preserved Ejection

Conditions
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Heart Failure, Diastolic

Intervention / Treatment
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* Diagnostic Test: Positive or negative pressure


Participation Criteria
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Eligibility Criteria
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Heart Failure Study Population Inclusion Criteria (Aim 1 and 2): Age greater than or equal to 30 yrs Established diagnosis of HFpEF with left ventricular ejection fraction greater than or equal to 50% NYHA II-III symptoms Stable HF drug regimen for the preceding 1 month Wedge pressure greater than or equal to 15 mmHg at rest or greater than or equal to 25 mmHg with peak exercise (For Aim 2 only) Scheduled for an elective right heart catheterization at Duke University Hospital. Exclusion Criteria (Aim 1 and 2): HF hospitalization for type I myocardial infarction within 3 months Infiltrative (ie amyloid) or hypertrophic cardiomyopathy Uncontrolled atrial or ventricular arrhythmia Chronic oxygen use History of vasovagal syncope Considered inappropriate to participate by PI or Sub-I Healthy Volunteers (Controls) Inclusion Criteria (Aim 1): Age greater than or equal to 30 yrs Able to speak English Ambulatory [assistive devices ok] Able to provide informed consent Exclusion Criteria (Aim 1): Acute myocardial infarction (3-5 days) Unstable angina Uncontrolled arrhythmia causing symptoms or haemodynamic compromise Syncope Active endocarditis Acute myocarditis or pericarditis Symptomatic severe aortic aneurysm Uncontrolled asthma Arterial desaturation at rest on room air <85% Untreated left main stem coronary stenosis Asymptomatic severe aortic stenosis Severe untreated arterial hypertension at rest (>200 mm Hg systolic, >120 mm Hg diastolic) Tachyarrhythmias or bradyarrhythmias Hypertrophic cardiomyopathy Significant pulmonary hypertension Thrombosis of the lower extremity until treated for a minimum of 2 weeks Within 2 weeks of acute symptomatic pulmonary embolus Abdominal aortic aneurysm >8.0 cm Electrolyte abnormalities Pregnancy Inmate of correctional facility (i.e. prisoner) Diagnosed history of dementia Inability to ambulate independently Considered inappropriate to participate by Principal Investigator

Ages Eligible for Study
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Minimum Age: 30 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Experimental: Patients with heart failure (Aim 1)<br> | Diagnostic Test: Positive or negative pressure<br>* Positive or negative pressure is applied via a closed chamber.<br>|
| Active Comparator: Control: Healthy Volunteers (Aim 1)<br> | Diagnostic Test: Positive or negative pressure<br>* Positive or negative pressure is applied via a closed chamber.<br>|
| Experimental: Experimental: Patients with heart failure (Aim 2)<br> | Diagnostic Test: Positive or negative pressure<br>* Positive or negative pressure is applied via a closed chamber.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| change in exercise cardiac output | Change in cardiac output from rest to 0 Watts exercise | Day 1 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| change in exercise cardiac output | Change in cardiac output from rest to 20 Watts exercise | Day 1 | 
| change in heart rate | Change in heart rate from rest to 0 Watts exercise | Day 1 | 
| change in heart rate | Change in heart rate from rest to 20 Watts exercise | Day 1 | 
| change in respiratory rate | Change in heart rate from rest to 20 Watts exercise | Day 1 | 
| change in O2 consumption | Change in O2 consumption from rest to 0 Watts exercise | Day 1 | 
| change in O2 consumption | Change in O2 consumption from rest to 20 Watts exercise | Day 1 | 
| Change in wedge pressure | Change in wedge pressure from rest to 0 Watts exercise | Day 1 | 
| Change in wedge pressure | Change in wedge pressure from rest to 20 Watts exercise | Day 1 |