Hammon 1984.

Methods	RCT, parallel design
Participants	Total number of randomized participants: 50 Inclusion criteria: scheduled for CABG, with stable angina pectoris Exclusion criteria: congestive heart failure, history of bronchospasm, previous sensitivity to propranolol Type of surgery: elective CABG Baseline characteristics not reported Country: USA Setting: single centre; hospital
Interventions	Intervention group (propranolol) Randomized, n = 24; losses = 0; analysed, n = 24 (use of ITT analysis not reported) Details: weaned from any previous propranolol use during 24‐48 h. Then on arrival at the ICU, 60 mg propranolol every 6 h via nasogastric tube until participant could take drug orally. Continued for 1 month Control group (placebo) Randomized, n = 26; losses = 0; analysed, n = 26 Details: placebo agent, given same as intervention group
Outcomes	Outcomes measured/reported by study authors: haemodynamic parameters, atrial and ventricular arrhythmias, death, MI, bradycardia (HR < 60 bpm) Outcomes relevant to the review: ventricular arrhythmias, death, MI, bradycardia
Notes	Funding/declarations of interest: study drug provided by pharmaceutical company (Ayerst Laboratories) Study dates: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Random number table
Allocation concealment (selection bias)	Unclear risk	Not specified
Blinding of participants and personnel (performance bias) All outcomes	Low risk	Randomized, placebo‐controlled, double‐blind trial
Blinding of outcome assessors (detection bias) All outcomes	Unclear risk	Not specified
Incomplete outcome data (attrition bias) All outcomes	Low risk	No apparent losses
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	High risk	Study authors do not report baseline characteristics and we could not be certain whether these characteristics were balanced between groups. In addition, we noted that antiarrhythmic therapy, which included propranolol, was given to 11 participants in the control group and 5 participants in the intervention group. This may have influenced outcome data