While there is clear evidence for administering unfractionated heparin after systemic thrombolysis, there are not randomised trials supporting the usefulness of postprocedural heparin in the setting of primary angioplasty, especially in the era of glycoprotein IIb/IIIa inhibitors, and this issue is still a matter of debate. In this review we analysed the 30-day cardiac events of patients treated with primary angioplasty and abciximab, with or without postprocedural unfractionated heparin. We conducted a Medline search and eight studies were selected: in four of them heparin was continued for at least 12 h after the procedure (group 1), in the others heparin was used only during the procedure (group 2). The composite incidence of 30-day major adverse cardiac events was similar in the two groups (5.1 vs. 5.1%; 95% confidence interval 0.66-1.45; P = 0.91), whereas total bleeding occurred in 5.5% of group 1 compared with 3% of group 2 (relative risk 1.82; 95% confidence interval 1.19-2.80; P = 0.005). In conclusion, this review suggests that in the setting of primary angioplasty with concomitant glycoprotein IIb/IIIa inhibitors, postprocedural heparin does not appear to favourably affect cardiac and systemic ischaemic events and turns out to be associated with an increase in haemorrhagic complications.