Preemptive Pharmacogenetic-guided Metoprolol Management for PostoperativeAtrial Fibrillation in Cardiac Surgery

Metoprolol is frequently administered to cardiac surgery patients to reduce the incidence of postoperative atrial fibrillation (PoAF). Metoprolol is metabolized by the enzyme CYP2D6, which is known to have many mutations that could influence a patient's ability to metabolize the drug. In this prospective clinical trial, the investigators will determine the genotype of CYP2D6 for patients undergoing cardiac surgery, provide an altered dosing recommendation for metoprolol, then report the relative effectiveness in managing PoAF for each pharmacogenetic- guided dosing category. The investigators will also explore the effects of personalized metoprolol dosing recommendations on outcomes in hospital length of stay, cost, and provider participation.