Comparison 1. Beta‐blocker vs control for cardiac surgery.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 All‐cause mortality (30 days)	29	4099	Risk Ratio (M‐H, Random, 95% CI)	0.95 [0.47, 1.90]
2 Long‐term mortality	3	511	Risk Ratio (M‐H, Random, 95% CI)	0.90 [0.29, 2.79]
3 Death due to cardiac causes	4	320	Risk Ratio (M‐H, Random, 95% CI)	0.84 [0.14, 5.19]
4 Acute myocardial infarction	25	3946	Risk Ratio (M‐H, Random, 95% CI)	1.05 [0.72, 1.52]
5 Cerebrovascular events	5	1471	Risk Ratio (M‐H, Random, 95% CI)	1.37 [0.51, 3.67]
6 Ventricular arrhythmias	12	2296	Risk Ratio (M‐H, Random, 95% CI)	0.40 [0.25, 0.63]
7 Atrial fibrillation or flutter, or both	40	5650	Risk Ratio (M‐H, Random, 95% CI)	0.50 [0.42, 0.59]
8 Bradycardia	12	1640	Risk Ratio (M‐H, Random, 95% CI)	1.63 [0.92, 2.91]
9 Hypotension	10	1538	Risk Ratio (M‐H, Random, 95% CI)	1.84 [0.89, 3.80]
10 Congestive heart failure	3	311	Risk Ratio (M‐H, Random, 95% CI)	0.22 [0.04, 1.36]
11 Length of hospital stay (in days)	14	2450	Mean Difference (IV, Random, 95% CI)	‐0.54 [‐0.90, ‐0.19]