Exercise Lower-body Negative Pressure in Heart Failure With Preserved Ejection Fraction

Summary

The heart is a pump that must both fill and empty effectively to move blood; if it cannot move enough, heart failure may ensue. Approximately half of all adults living with heart failure have a form where the heart stiffens, which impairs its ability to fill. This form of heart failure particularly affects females and older adults. When people exercise, extra blood returns to the heart. The healthy heart can easily fill and move this extra blood to the muscles. However, when the heart's ability to fill is impaired, the extra blood can back up and pool in the lungs. Blood pooling in the lungs makes people feel breathless, although the investigators do not fully understand why, and this form of heart failure has a high risk of hospitalization and death, but few effective treatments are available. Exercise is one of the few treatments that works well if enough exercise is performed regularly. However, many people with this form of heart failure can only tolerate a small amount before stopping due to severe breathlessness, which can put them off from exercising regularly.

The study's goal is to help these people perform more exercise. The investigators will use a novel form of stationary cycling with a plastic chamber around the lower body that seals at the waist. The chamber can apply suction to the lower body during exercise which will reduce how much extra blood returns and prevent the heart and lungs from being overloaded. Participants will attend 5 visits, including 3 where they will perform a submaximal exercise test for as many minutes as possible with or without light suction. In each of these tests, the investigators will record how long they exercise and ask them to rate how breathless they feel. The investigators will also study their breathing pattern, using a mouthpiece and pressure sensor, and heart function, using ultrasound imaging.

This work will help adults living with heart failure exercise more and improve their health, and help researchers understand what causes breathlessness and develop new treatments.

Conditions

• Heart Failure With Preserved Ejection Fraction

Interventions

OTHER

Lower-body Negative Pressure (-25 mmHg)

The LBNP chamber will be sealed at the waist prior to Control measures, and the vacuum system will be activated to coincide with the onset of exercise, applying -25mmHg LBNP.

OTHER

Lower-body Negative Pressure (-15 mmHg)

The LBNP chamber will be sealed at the waist prior to Control measures, and the vacuum system will be activated to coincide with the onset of exercise, applying -15mmHg LBNP.

OTHER

Lower-body Neutral Pressure (0 mmHg)

In this placebo trial, the LBNP chamber will be sealed at the waist prior to Control measures, and the vacuum system will be activated to coincide with the onset of exercise, but the chamber will be vented to atmosphere.

Sponsors & Collaborators

• University of British Columbia

  lead OTHER

Principal Investigators

• Neil D Eves, PhD · The University of British Columbia

Study Design

Allocation

NON_RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

CROSSOVER

Eligibility

Min Age

40 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2023-01-25

Primary Completion

2026-01-31

Completion

2026-01-31

Countries

• Canada

Study Locations