Unfractionated heparin use after percutaneous coronary intervention: results of a trial with a vascular ultrasound endpoint

Previous studies in the pre-stent era have evaluated the postprocedural use of unfractionated heparin (UFH) on clinically defined vascular complications and ischaemic cardiac complications. We prospectively evaluated the benefits and risks of this practice, using vascular ultrasound determined endpoints in the current stent era.

Patients undergoing percutaneous coronary intervention (PCI) and enrolled in two of our previous routine and prospective vascular ultrasound studies were included in the analysis. Generally the decision to use UFH after sheath removal was at the discretion of the operator, however a subset of patients was randomised to receive UFH or not. Femoral vascular ultrasound was performed prior to hospital discharge and interpreted by an experienced vascular ultrasonographer blinded to whether UFH was used or not. The primary endpoint was a composite of significant vascular ultrasound determined complications including major haematoma, pseudoaneurysm, arterio-venous fistula, femoral venous or arterial thrombosis and retroperitoneal haemorrhage. Secondary endpoints included in hospital ischaemic events, length of stay and outcome at 30 days.

A total of 530 patients (43% receiving UFH) were included in the analysis. The incidence of the primary endpoint for the entire population was 4.0% in both the UFH and no UFH groups (p=1.00). In the 226 (43%), randomised patient subset, the primary endpoint occurred in 5.2% in the UFH group and 4.5% in the no UFH group (p=0.80). Time to ambulation and discharge was similar in both groups. At 30 days, the incidence of major adverse cardiac events (4.7% for entire cohort) was similar in all groups whether randomised or not.

When vascular ultrasound is used to determine major vascular complications the use of UFH after PCI in the stent era was not associated with increased major vascular complications. We also failed to provide evidence of a meaningful clinical benefit with the routine use of postprocedural heparin in this selected patient cohort.