Muscle Blood Flow Regulation in HFpEF

This study is investigating why people with heart failure with preserved ejection fraction (HFpEF) — a type of heart failure where the heart pumps normally but is too stiff — have poor exercise tolerance. Specifically, it looks at whether blood flow to muscles during exercise is impaired and what role the nervous system plays. Understanding this could lead to better treatments. **You may be eligible if...** - You are 18 or older with diagnosed HFpEF (heart failure where the pumping fraction is above 50%) - You are in NYHA class II or III (meaning you have symptoms during moderate or mild activity) - Your BNP or NT-proBNP levels are elevated (a blood marker of heart stress) - You are stable on your current heart medications **You may NOT be eligible if...** - Your heart pumping fraction has ever been below 50% - You have NYHA class IV heart failure (symptoms at rest) that cannot be stabilized - You have had a recent heart attack, myocarditis, or have a condition like cardiac sarcoidosis - You have an orthopedic problem that prevents you from doing leg exercises - You are a woman taking hormone replacement therapy or currently pregnant - You are a current smoker Talk to your doctor to see if this trial is right for you.