This is an open-label, non-inferiority, randomized comparison of beta-blocker continuation versus de-prescription at the 6-8 week follow-up following isolated and uncomplicated CABG at Royal University Hospital, Saskatoon.~Patients treated with isolated CABG (without valve repair/replacement) and discharged on a beta-blocker are eligible for recruitment if they have preserved systolic function (EF ≥45%) and no history of heart failure, atrial fibrillation/flutter, or an alternate compelling indication for beta-blocker therapy. After obtaining informed consent, eligible patients are randomly assigned at 6-8 weeks to one of the two treatment groups: continued beta-blocker therapy per their usual clinical care OR beta-blocker de-prescription as per the study protocol.~The primary objective of this study is to demonstrate recruitment feasibility for beta-blocker de-prescription 6-8 weeks following uncomplicated CABG. Exploratory outcomes include the composite of all-cause mortality, myocardial infarction, stroke, arrhythmia, and cardiovascular-related hospitalization (congestive heart failure, recurrent ischemia, arrhythmia [supraventricular including atrial fibrillation, and ventricular], syncope or need for pacemaker) over a 3-year follow up duration.~Other exploratory outcomes will include a change in the patient reported quality of life using the Short Form (SF) 36 and Euro Qol (EQ) 5D questionnaires and angina score using the Seattle Angina Questionnaire (SAQ).
Beta-blockers have the greatest cardiovascular impact in patients with reduced heart function/heart failure and in reducing the peri-operative risk of atrial fibrillation. In patients without these high-risk features treated with coronary artery bypass graft (CABG) surgery, their continued long-term role is unclear.