Forty-six studies were included in the review and meta-analyses (44,924 patients): 19 RCTs (10,944 patients, from 102 to 1,829 per study) and 27 observational studies (33,980 patients, from 59 to 6,479 per study). Only RCT data were included in the meta-analyses.
At 30-days follow-up, coronary artery bypass grafting demonstrated statistically significantly higher rates of stroke than percutaneous coronary intervention (OR 2.94, 95% CI 1.69 to 5.09; 14 RCTs; Ι²=0%); results were identical for the fixed-effect and random-effects models. The number-needed-to-harm was 155, with an additional seven strokes for every 1,000 patients treated with coronary artery bypass grafting rather than percutaneous coronary intervention. No statistically significant interactions were reportedly observed between the revascularisation methods and the period within which these studies were performed (p=0.25), the extent of coronary artery disease in patients (p=0.57), and the use of stents instead of balloon angioplasty only (p=0.52).
After a median follow-up period of 12.1 months, coronary artery bypass grafting demonstrated statistically significantly higher rates of stroke than percutaneous coronary intervention using the fixed-effect model (OR 1.67, 95% CI 1.09 to 2.56; 12 RCTs; Ι²=4.8%) and the random-effects model (OR 1.69, 95% CI 1.07 to 2.67). No statistically significant interaction was observed between revascularisation method and the extent of coronary artery disease.
In observational studies, coronary artery bypass grafting demonstrated a statistically significantly increased risk of stroke over percutaneous coronary intervention, both at 30 days (27 studies) and at a median follow-up of 14.2 months (13 studies). Details reported in paper.
No statistically significant heterogeneity was observed across the RCTs or the observational studies overall, or within the subgroups analysed (Ι² range: 0 to 7.5%). No evidence of publication bias was found.