Overview
This is a prospective study to evaluate changes in exercise capacity and chronotropic response to exercise before and after beta-blocker dosage reduction in patients with atrial fibrillation (AF).
Description
Rate control therapy is the first-line treatment for atrial fibrillation (AF). Resting heart rate(HR) is the treatment target of rate control therapy in current clinical practice; However, the optimal value for resting heart rate in AF remained unclear. Beta-blocker(BB) is widely used as rate-control agent. It is concerned that excessive use of BB might lead to a negative effect on exercise capacity in patients with AF. The aim of this study is to explore the effect of Beta-blocker on hemodynamic parameters and peak oxygen uptake during cardiopulmonary exercise test (CPET).
Eligibility
Inclusion Criteria:
- > 20 years of age.
- Clinically stable patients with persistent atrial fibrillation using beta-blocker as rate-control agent without dosage adjustment for at least 3 months.
- Resting heart rate < 80 bpm.
- Left ventricular ejection fraction > 50%.
Exclusion Criteria:
- Beta-blocker usage due to indications other than rate control for atrial fibrillation.
- Inability to perform a cardiopulmonary exercise testing.
- Presence of contraindications for cardiopulmonary exercise testing according to the American College of Sports Medicine's Guidelines for Exercise Testing and Prescription.
- Patients with implantable cardioverter defibrillator or pacemaker.
- Pregnancy.
- Inability to provide informed consent.