Ivabradine for Heart Rate Reduction During Exercise in Healthy Adults (NCT07717710)
🩺 Plain-English Summary (8th-Grade Level)
During exercise, working muscles require more oxygen. The heart meets this demand in two ways: by beating faster (heart rate) and by pumping more blood with each beat (stroke volume). Heart rate increases steadily with exercise intensity until exhaustion, but the amount of blood pumped with each beat tends to plateau at moderate intensities. Why the amount of blood pumped with each beat becomes limited before heart rate, however, is not well understood. Studying these mechanisms is difficult because most drugs that lower heart rate also affect how strongly the heart pumps, making it hard to separate the two effects. One medication that can help with this is ivabradine, which is used to treat people with heart disease who have high resting heart rates. It slows the heart rate without changing how strongly the heart pumps. This study will investigate whether ivabradine lowers heart rate during exercise in healthy younger and older adults, and whether a higher dose lowers heart rate more. The results will help us better understand how heart rate influences the heart's ability to supply oxygen to the body during exercise, and what limits the ability to exercise as people age. Participants will: * Attend three visits at SportsCardiologyBC in Vancouver * Complete a cycling exercise test at each visit to measure heart rate and how hard they can exercise * Take ivabradine (a heart-rate-lowering medication) before the exercise test at Visits 2 and 3 (a lower dose at Visit 2 and a higher dose at Visit 3) * Be monitored for side effects including slow heart rate, visual symptoms, and headache.
Who can join: To join this study, participants generally need to meet the listed inclusion criteria (2 items) and avoid the listed exclusions (19 items).
Location: SportsCardiologyBC, UBC Hospital — Vancouver, British Columbia
📋 "Do I Qualify?" — 1-Minute Self Screener
Instant ChecklistCheck every box below. If you can check all of them, you may meet the study's basic screening requirements (final eligibility is confirmed by the site team).
Usually NOT eligible if any of the following apply:
- Exclusion Criteria:
- History of any cardiovascular condition, including hypertension
- Use of any chronic medication
- History of any respiratory condition, including asthma
- Smoking, including cannabis or vaping in the past year
- History of diabetes mellitus, cancer, hepatic, renal or any other chronic illness
- Seated blood pressure ≥130/90 or \<100/60 mmHg
- Body mass index \<20 or \>32 kg/m2
- Non-sinus rhythm or abnormalities on 12-lead electrocardiogram (ECG)
- Pregnant, breastfeeding, or women of childbearing potential not using appropriate contraception
- Current or recent (past year) participation in \>150 minutes per week of moderate-vigorous intensity exercise (to avoid endurance training-related bradycardia)
- Any condition that prevents vigorous exercise from being performed safely
🔍 Extracted verbatim from the official NIH eligibility criteria. Always confirm with the study coordinator.
📍 All Participating Trial Locations (1 Sites)
- SportsCardiologyBC, UBC Hospital — Vancouver, British Columbia
💰 Cost, Insurance & Patient Rights
- 100% Free Items: The investigational treatment and protocol-required procedures are supplied at zero cost by the sponsor.
- Routine Patient Care: Under federal law (ACA § 2709) and many state statutes, routine care costs are covered during participation.
- Voluntary Participation: You may withdraw at any time without affecting your standard medical care.