No randomized trial has been conducted to directly compare enoxaparin with unfractionated heparin (UFH) in patients undergoing percutaneous coronary intervention (PCI) for non-ST-segment elevation acute coronary syndrome (NSTE-ACS). In an era where early invasive strategies are recommended in high risk patients, the effect of enoxaparin and UFH needs to be re-evaluated. The authors performed a meta-analysis to determine whether enoxaparin is superior to UFH in patients with NSTE-ACS undergoing PCI.
The composite efficacy end point included all-cause mortality and myocardial infarction (MI) in the hospital or within 60 days. Major bleeding, as defined in the individual clinical trials evaluated, was the main safety endpoint within the same time period. Pooled estimates of the difference in outcome between enoxaparin and UFH were calculated using fixed or random effects models.
A total of 8,861 patients from 4 trials were included. In the pooled analysis, rates of death or MI were similar in patients treated with enoxaparin and UFH [risk ratio (RR), 0.89, 95% confidence interval (CI): 0.77–1.02, P=0.09; I2 =50%]. Major bleeding was also similar between enoxaparin and UFH (RR, 1.21, 95% CI: 0.94–1.56, P=0.15, I2=39%). A subgroup analysis, including randomized trials only or trials with a large sample size, and a leave-one-out sensitivity analysis, demonstrated similar results with above, respectively.
In patients undergoing PCI for NSTE-ACS, rates for both death/MI and major bleeding were similar between patients treated with enoxaparin and UFH.