Patients ≥ 18 years of age with paroxysmal or persistent AF who have an implantable cardiac monitor (either loop recorder or pacemaker) and who are receiving daily beta-blocker therapy will be screened for meeting the inclusion/exclusion criteria.~Trial participants will then be randomized into the daily beta-blocker or as-needed pharmacological rate control.~At baseline and six months trial participants will undergo assessment of the following measures:~Assessment of Quality of life using the Minnesota Living with Heart Failure Questionnaire and the Atrial Fibrillation Effect on Quality of life Questionnaire.~Blood draw~Cardiopulmonary exercise test, 6 Minute Walk Test and average daily activity level via integrated accelerometer of the implantable cardiac monitor (if available).~Assessment of AF burden~Study participants may opt into long-term follow up visits at 12, 18 and 24 months.~Chart review will continue for up to 4 years after enrollment for the purpose of monitoring clinical endpoints:~Heart failure events (diuretic drug change, emergency room visit, hospitalization)~AF events (hospitalization, emergency room visit, cardioversion, antiarrhythmic medication initiation)~Stroke or transient ischemic attack~Myocardial infarction
The goal of this study is to test the feasibility of guiding as-needed pharmacological rate control of atrial fibrillation (AF) by implantable cardiac monitors and to assess the impact of continuous beta-blocker therapy versus as-needed rate control on the following outcomes:~(1) exercise capacity, (2) AF burden, (3) symptomatic heart failure, (4) biomarker assessment of cardiac filling pressures and cardio-metabolic health, and (5) quality of life in patients with atrial fibrillation and stage II or III heart failure with preserved ejection fraction.