The goal of this clinical trial is to learn if a high-flow nasal cannula (HFNC) - a device that delivers warm, humidified air through a small tube placed in the nostrils - can improve exercise tolerance in adults with heart failure (HF) who are entering a cardiac rehabilitation program. The main questions it aims to answer are: Can HFNC help people with heart failure exercise for a longer time during a treadmill test? and does HFNC lower how hard people feel they are working during exercise?
Researchers will compare exercise performance with HFNC to exercise performance without HFNC to see if HFNC helps people with HF tolerate exercise better. Participants will:
Complete two treadmill exercise tests, one with HFNC and one without, in a randomly assigned order.
Wait 48 to 72 hours between the two tests to allow full recovery. Have their heart rate, blood pressure, oxygen level, and breathing rate measured before and after each test.
Age 18 years or older
Medical diagnosis of heart failure (documented in clinical record or referral)
Electrocardiogram performed within the last 6 months
Functional capacity class II or III according to the New York Heart Association (NYHA) classification
Diagnosis of respiratory disease (chronic obstructive pulmonary disease, interstitial lung disease, or pulmonary hypertension)
Myocardial infarction within the past 3 months
Hospitalization due to heart failure within the past 4 weeks
Cognitive impairment or inability to follow the study protocol