Objective: This study was designed to examine the efficacy and safety of a dose of 0.75 mg/kg intra-arterial enoxaparin in elective percutaneous coronary intervention in Chinese population.
Methods: A total of 160 consecutive patients undergoing elective PCI were randomized to either enoxaparin or UFH (80 cases for each) group for procedural anticoagulation. The patients in enoxaparin group were given a bolus of enoxaparin (0.75 mg/kg) intra-arterially before PCI, and a superaddition (0.3 mg/kg) would be administered if the procedural time > 90 minutes. Serial plasma anti-X a factor activities were measured before and after the bolus of enoxaparin. The patients in UFH group were given a bolus of UFH (100 U/kg) intra-arterially before PCI and ACT was controlled between 250 and 300 seconds. Then coronary angiography and PCI was performed immediately. Bleeding complications were classified according to thrombolysis in myocardial infarction (TIMI) criteria. All patients were monitored for thrombosis during PCI and adverse events (i.e. death, myocardial infarction demanding revascularization) 30 days after PCI.
Results: 159 patients completed the procedure. Plasma anti-X a factor activities in patients of the enoxaparin group were above 0.5 IU/ml 5 minutes to 2 hours after enoxaparin (0.75 mg/kg) injection and the measurements in 61% of the patients were above 0.5 IU/ml 3 hours after injection. If a supplement of 0.3 mg/kg of enoxaparin was given after 90 minutes, plasma anti-X a factor activities of all the patients were above 0.5 IU/ml within 4 hours after the procedure. As compared with UFH, enoxaparin increased the likelihood of thrombosis significantly in sheath catheter during PCI (26.6% vs 10.0%, P < 0.001). There was no obvious difference in adverse events (2.5% vs. 2.6%, P > 0.05) and bleeding events (2.5% vs 3.8%, P > 0.05) between the two groups.
Conclusions: A 0.75 mg/kg intra-arterial dose of enoxaparin for anticoagulation in patients undergoing elective PCI is safe and effective. Anticoagulation effect can be maintained for at least 2 hours. An additional bolus is proposed when procedure time exceeds 2 hours.