Yazicioglu 2002.

Methods	RCT, parallel design
Participants	Total number of randomized participants: 80 Inclusion criteria: people who had undergone elective CABG surgery Exclusion criteria: undergone re‐operation, concomitant valve surgery, ventricular aneurysm resection or other major cardiac procedures; 2nd‐ or 3rd‐degree atrioventricular block; bradycardia; asthma necessitating bronchodilator therapy; COPD; history of preoperative AF and AF episodes; diabetes mellitus; renal failure; left ventricular aneurysm; left ventricular ejection fraction < 30%; needing inotropic support preoperatively Type of surgery: elective CABG surgery Baseline characteristics Intervention group (atenolol) Age, mean (SD): 57.1 (± 7.3) years Gender, M/F: 32/8 History of MI, n: 4 History of hypertension, n: 12 Ejection fraction, mean (SD), %: 52 (± 6.1) Control group (placebo) Age, mean (SD): 55.3 (± 8.1) years Gender, M/F: 30/10 History of MI, n: 5 History of hypertension, n: 9 Ejection fraction, mean (SD), %: 50 (± 5.7) Country: Turkey Setting: single centre; hospital
Interventions	Intervention group (atenolol) Randomized, n = 40; losses = 1 (excluded due to death; we re‐included this participant in data for mortality); analysed, n = 39 (except for mortality, for which we included 40 participants in analysis) Details: 50 mg atenolol, given orally, starting 3 days before surgery and maintained with the same dose after surgery Control group (placebo) Randomized, n = 40; losses = 0; analysed, n = 40 Details: placebo, given the same as the intervention group
Outcomes	Outcomes measured/reported by study authors: mortality (due to stroke); AF, return to sinus rhythm, HR, side effects (to include bradycardia and hypotension) Outcomes relevant to the review: mortality; AF
Notes	Funding/declarations of interest: not reported Study dates: March 1999‐December 1999 Notes: study included additional groups (digoxin; atenolol + digoxin), which we did not include in the review we did not include data for bradycardia and hypotension in analysis because we could not be certain whether these data were measured in participants in all groups. 12 participants in the atenolol group had bradycardia, of whom 9 also had hypotension.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not specified
Allocation concealment (selection bias)	Unclear risk	Not specified
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Although study includes a placebo, it is not reported whether anaesthetists were blinded to study drugs
Blinding of outcome assessors (detection bias) All outcomes	Unclear risk	Not specified
Incomplete outcome data (attrition bias) All outcomes	Low risk	1 participant in the intervention group was excluded from further analysis due to death. We re‐included this participant in analysis of mortality.
Selective reporting (reporting bias)	Unclear risk	Study authors did not report prospective clinical trial registration or publication of a protocol. It was not feasible to effectively assess risk of reporting bias
Other bias	Low risk	Not detected

2D: two‐dimensional; ACE inhibitor: angiotensin‐converting‐enzyme inhibitor; AF: atrial fibrillation; AMI: acute myocardial infarction; ASA: American Society of Anesthesiologists; bpm: beats per minute; BP: blood pressure; CABG: coronary artery bypass graft; COPD: chronic obstructive pulmonary disease; CPB: cardiopulmonary bypass; CVA: cerebrovascular accident; ECG: electrocardiogram; GA: general anaesthesia; GI: gastrointestinal; HR: heart rate; IAB: intra‐aortic balloon; IABP: intra‐aortic balloon pump; ICU: intensive care unit; IQR: interquartile range; ITT: intention‐to‐treat; IV: intravenous(ly); LSD: lysergic acid diethylamide; MACE: major adverse cardiovascular event; M/F: male/female; MI: myocardial infarction; NIH: National Institutes of Health; NYHA: New York Heart Association; PCWP: pulmonary capillary wedge; pressure; Q waves: name given to a wave on an electrocardiogram; QRS: a measure of three waves on an electrocardiogram; QTc: corrected QT interval; QT: interval measurement on an electrocardiogram; RCT: randomized controlled trial; SBP: systolic blood pressure; SD: standard deviation; SE: standard error; SEM: standard error of the mean; ST segment: a period between waves on an electrocardiogram; SVA: supraventricular arrhythmia; SVT: supraventricular tachycardia; TIA: transient ischaemic attack