In the OASIS 2 trial, 10 141 patients with non-ST-elevation
acute coronary syndrome were randomized to 72 h of intravenous
hirudin or
unfractionated heparin.
Percutaneous coronary intervention was performed at the discretion of the investigator. One hundred and seventeen patients underwent
percutaneous coronary intervention within the first 72 h ("early
percutaneous coronary intervention"). In patients undergoing early
percutaneous coronary intervention,
hirudin compared with
unfractionated heparin was associated with a significantly lower incidence of death or
myocardial infarction at 96 h (6.4% vs 21.4%, OR 0.30; 95% CI: 0.10-0.88) and 35 days (6.4% vs 22.9%, OR 0.25; 95% CI: 0.07-0.86). In the
unfractionated heparin group, death or
myocardial infarction was significantly higher at 35 days in patients undergoing early
percutaneous coronary intervention compared with those managed conservatively (22.9% vs 7.3%, OR 3.14, P<0.001) but this early
percutaneous coronary intervention-related hazard was not observed in
hirudin-treated patients (6.4% vs 6.8%, OR 0.94 P=1.0). A time-dependent covariate for
percutaneous coronary intervention was not significant in a Cox regression model, suggesting a similar treatment benefit with
hirudin before and after
percutaneous coronary intervention. After adjustment for
percutaneous coronary intervention propensity, the benefits of
hirudin remained significant. There were three major bleeds in patients undergoing early
percutaneous coronary intervention, all in patients randomized to
hirudin.
CONCLUSION: