Eligible studies were of patients with unprotected left main coronary artery disease who underwent treatment with percutaneous coronary intervention with stents (bare metal or drug-eluting stents) compared with coronary artery bypass grafting (conventional or off-pump) using either randomised controlled trial (RCT) or non-randomised observational study methods. Outcomes at follow-up included death, repeat revascularisation or major adverse cardiac and cerebrovascular events, prevention of death, myocardial infarction, stroke and repeated revascularisation.
Mean/median patient age ranged from 60.6 to 81. The proportion of males ranged from 50% to 76%. Ejection fraction ranged from 50 to 61%. The proportion of drug-eluting stents ranged from 35% to 100%. Off-pump coronary artery bypass grafting ranged from 0% to 42%. Percutaneous coronary interventions with stents varied, but most studies included aspirin indefinitely together with clopidogrel or ticlopidine. The percentage of patients with coexisting conditions ranged from 17% to 36% for diabetes, 49% to 88% for hypertension and 29% to 74% for hyperlipidaemia.
The authors did not state how many reviewers selected studies for inclusion.