Abstract

Optimal weight based unfractionated heparin dosing during percutaneous coronary intervention

Author(s): Ray Sriratana Tabucanon*, Muenpetch Muenkeaw

Introduction: Unfractionated Heparin (UFH) is a potent and preferable anticoagulant agent during Percutaneous Coronary Intervention (PCI). Activated clotting time (ACT) is a good assay for accurate titration of UFH during PCI; however, the optimal range of ACT during PCI is narrow (250-300 sec by Hemotech system). The guideline recommendation of the loading dose of UFH is 70 U/Kg-100 U/Kg but the optimal loading dose is unclear. The aim of this study was to evaluate the number of optimal ACT levels 30 min after administration of 70 U/kg, 80 U/kg, 90 U/kg and 100 U/ kg IV UFH.

Method: This study was performed in Thammasat University Hospital from February 15, 2019 to March 15, 2019. Forty patient candidates for PCI were enrolled in the study. Patients were randomized into 4 groups (1:1:1:1), 70 U/kg, 80 U/kg, 90 U/ kg and 100 U/kg IV UFH (10 patients per group). Data including demographic and risk factors were collected. Baseline ACT and ACT 30 min after IV bolus UFH were measured using Hemotech system. The primary study objective was to determine the number of ACT in the therapeutic range. The secondary objectives were divided into efficacy endpoint (thrombotic events) and safety endpoint (bleeding as defined by the Bleeding Academic Research Consortium criteria).

Result: The median of baseline ACT were 148, 148, 150 and 148 sec respectively (χ²=0.106, dF=3, P=0.991). The median of ACT 30 min after IV bolus UFH were 227, 235, 257 and 275 sec respectively (χ²=7.2, dF=5.728, p=0.126). The number of ACT in the therapeutic range was 0 (0%) in 70 U/kg, 3 (30%) in 80 U/kg, 3 (30%) in 90 U/kg, 5 (50%) in 100 U/kg (χ²=6.716, dF=3, p=0.083). There was one event of minor bleeding in the 100 U/kg group. No thrombotic event was observed in this study.

Conclusion: The finding suggested that there is no statistically significant difference among groups. The 100 U/kg IV UFH may tend to achieve the most optimal ACT level in patients who underwent percutaneous coronary intervention.