Tests suction-assisted cycling in people with a stiff-heart form of heart failure

Trial details

Who runs it

University of British Columbia

Trial code

NCT05582044

Record updated

4 April 2025

Original description

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.Read full original descriptionShow less

The Effect of Lower-body Negative Pressure on Exercise Tolerance and Mechanisms of Dyspnea in Heart Failure With Preserved Ejection Fraction

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.

Inclusion: Adults with a clinical diagnosis of HFpEF (LV ejection fraction ≥50%) measured in the year prior to Visit 1 (and confirmed at Visit 1), who are New York Heart Association Functional Class II-III (mild-moderate symptoms), ambulatory, receiving guideline-directed medical therapy unchanged for ≥2 months, and clinically stable for ≥3 months; Symptom(s) of heart failure requiring treatment within the year prior to Visit 1; NT-proBNP >50 pmol/L (sinus rhythm) or >150 pmol/L (atrial fibrillation in year prior); Diastolic dysfunction based on at least one of the following echocardiographic findings:; Left atrial enlargement (diameter >4 cm or volume index >28 mL/m2); or; e' <10 cm/s (lateral) or <8 cm/s (septal), or; E/e' >10 (lateral), or >15 (septal); Healthy sedentary or recreationally active adults from the community.

Exclusion: Primary pulmonary, metabolic, renal, hepatic, neuromuscular, or malignant disease; Primary pulmonary vascular, complex congenital, or > mild valvular heart disease; Documented valvular or coronary disease requiring intervention; Myocarditis, pericardial effusion, acute coronary syndrome, or revascularization in the last 3 months; History of any cardiovascular condition or cardioactive drug use; History of any respiratory condition including asthma; History of any metabolic condition including diabetes; Any other chronic systemic illness; Any prior measurement demonstrated LV ejection fraction ≤40%; Echocardiographic evidence of significant left ventricular hypertrophy, valvular abnormalities, left ventricular ejection fraction <50%, or diastolic dysfunction as described in HFpEF inclusion criteria; Documented infiltrative cardiomyopathy; Resting seated systolic blood pressure >160 mmHg or <100 mmHg; Jugular venous pressure >12 cm; Inferior vena cava >2 cm with no inspiratory collapse, or severe right ventricular dysfunction by echo; Ambulatory supplemental oxygen; Current or recent participation in >150 min. per week of moderate intensity exercise; Current or recent (within the past 6 months) smoking; Body mass index >35 kg/m2; Contraindication to exercise or otherwise unable to perform cycle ergometry; Poor echocardiographic imaging windows; Current or recent participation in >150 min. per week of moderate intensity exercise; Non-sinus rhythm; Seated blood pressure ≥140/90 mmHg; Current or recent (within the past 6 months) smoking; Body mass index >35 kg/m2; Contraindication to exercise or otherwise unable to perform cycle ergometry; Poor echocardiographic imaging windows.

ClinicalTrials.gov NCT05582044