Activated clotting time (ACT)-guided intravenous dalteparin dosing during percutaneous coronary intervention.

BACKGROUND The activated clotting time (ACT) has been reported to be sensitive to the anticoagulant activity of the low-molecular weight heparin dalteparin following intravenous (IV) administration. OBJECTIVE To evaluate the feasibility of an ACT-guided dalteparin dose adjustment strategy during percutaneous coronary intervention (PCI). METHODS This was a retrospective study of 104 consecutive patients who underwent PCI using an ACT-guided strategy of IV dalteparin. All patients received an initial IV bolus of 50 IU/kg of dalteparin. The minimum target ACT was 175 seconds for patients who received glycoprotein IIb/IIIa inhibitors and 200 seconds for patients who did not. Patients who did not achieve the target ACT after the initial 50 IU/kg were given supplemental boluses of dalteparin based on the assumption that for every additional 10 IU/kg of dalteparin, the ACT will rise by approximately 10 seconds. RESULTS After the initial bolus of dalteparin, the mean baseline ACT rose from 138 +/- 41 seconds to 235 +/- 78 seconds. In the 36 patients (35% of the study population) who required a mean supplemental dose of 14 +/- 6 IU/kg/kg, the mean ACT after the supplemental dose was 239 +/- 79 seconds. The composite endpoint of in-hospital death, target vessel revascularization (TVR) and myocardial infarction (MI) was 5.8%. Major and minor bleeding rates were 1% each. The composite incidence of death/MI/TVR was comparable to, and the bleeding complications were lower than, those achieved in the SYNERGY and STEEPLE trials. CONCLUSION ACT-guided dose adjustment of intravenously administered dalteparin during PCI appears to constitute a feasible strategy.