We recommend that patients who have been receiving a β-blocker before cardiac surgery have that therapy continued through the operative procedure in the absence of the development of a new contraindication. (Recommendation Strong, Quality High)
We suggest that patients who have not been receiving a β-blocker before cardiac surgery have β-blocker therapy initiated just before or immediately after the operative procedure in the absence of a contraindication. (Recommendation Conditional, Quality Low)
Values and preferences: These recommendations place a high value on reducing postoperative AF and a lower value on adverse hemodynamic effects of β-blockade during or after cardiac surgery. It is also noted that inherent to a strategy of prophylaxis, a number of patients will receive β-blocker therapy without personal benefit.