RecruitingNot ApplicableNCT05332457

The Effect of Beta-blocker on Chronotropic Response and Cardiorespiratory Fitness in Patients With Atrial Fibrillation

The Effect of Beta-blocker on Chronotropic Response and Cardiorespiratory Fitness in Patients With Atrial Fibrillation: a Crossover Randomized Controlled Trial.

Sponsor

National Taiwan University Hospital

Enrollment

40 participants

Start Date

Jul 1, 2025

Study Type

INTERVENTIONAL

Conditions

Atrial Fibrillation

Summary

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).

Eligibility

Min Age: 20 Years

Inclusion Criteria4

\> 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 Criteria6

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.

Interventions

DRUGReduced dosage of beta-blocker

Phase I: 1. CPET performed at trough BB concentration: participants will undergo CPET at least 30 hours after last beta-blocker usage. 2. CPET performed at peak BB concentration : participants will undergo CPET at 3 hours after last beta-blocker usage. Phase II: BB dosage will be reduced.