Nine RCTs (n=28,759) were included in the review: 481 patients died at follow-up; 1,765 had a myocardial infaction; and 693 experienced a major bleeding complication. Follow-up ranged from two to 180 days; five studies reported 30 days.
There was no statistically significant difference in mortality between the bivalirudin and unfractionated heparin groups (1.73% versus 1.67%). The pooled OR was 0.88 (95% CI 0.73 to 1.06, p=0.18; nine RCTs) with statistically significant heterogeneity (I2>50%) in either a fixed-effect or a random-effects analysis. There was no significant relationship between treatment effect and baseline risk of mortality (p=0.71).
There was a trend toward a greater risk for myocardial infarction in the bivalirudin groups (6.9% versus 5.9%, OR 1.10, 95% CI 0.99 to 1.21, p = 0.07; eight RCTs) in both analyses with no evidence of heterogeneity (I2=0%).
Statistically significantly fewer patients experienced a major bleeding event in the bivalirudin groups (1.7% versus 3.4%, OR 0.51, 95% CI 0.44, 0.60; nine RCTs) with statistically significant heterogeneity (I2=50% in fixed-effect model and 42% in random-effects model). There was no relationship between treatment effect and baseline risk (p=0.16). There was no statistically significant effect of treatment group on risk of intracranial haemorrhage.