Age \>50 years

American Society of Anesthesiologists (ASA) risk status III-IV

Revised Cardiac Risk Index ≥2

β-blocker naïve (not having received β-blocker within 30 days prior to surgery)

Previously diagnosed coronary artery disease (CAD) or at high risk for CAD:

History of peripheral vascular disease, or

Diabetes and currently on oral anti-diabetic drug or insulin therapy, or

Chronic renal failure (eGFR \<30 m/min)

Major non-cardiac surgery under general anesthesia

Pilot - Peri-operative Beta Blockade