A novel point-of-care assay for the monitoring of low-molecular weight heparins in the cardiac catheterization laboratory

• Published in: The Journal of invasive cardiology Vol. 20; no. 9; pp. 449 - 454
• Main Authors: Marmur, Jonathan D, Lakhani, Manish, El Rouby, Soumaya, Cavusoglu, Erdal
• Format: Journal Article
• Language: English
• Published: United States 01.09.2008
• Subjects: Adult; Aged; Aged, 80 and over; Angioplasty, Balloon, Coronary; Anticoagulants - administration & dosage; Anticoagulants - therapeutic use; Cardiac Catheterization - methods; Dalteparin - administration & dosage; Dalteparin - therapeutic use; Enoxaparin - administration & dosage; Enoxaparin - therapeutic use; Female; Heparin, Low-Molecular-Weight - administration & dosage; Heparin, Low-Molecular-Weight - therapeutic use; Humans; Infusions, Intravenous; Male; Middle Aged; Monitoring, Intraoperative - methods; Point-of-Care Systems; Sensitivity and Specificity; Whole Blood Coagulation Time - methods
• ISSN: 1557-2501

We designed a study to compare the novel point-of-care assay Hemonox clotting time (Hemonox-CT) with the activated clotting time (ACT) and anti-Xa activity to monitor the anticoagulation effects of enoxaparin and dalteparin during percutaneous coronary intervention (PCI). A total of 90 patients undergoing cardiac catheterization were assigned to intravenous (IV) enoxaparin 0.5 mg/kg, dalteparin 50 international units/kg or unfractionated heparin (UFH) 50 units/kg. We measured Hemonox-CT, ACT and plasma anti-Xa levels after serial sampling. Baseline Hemonox-CT was similar in the enoxaparin (68 +/- 9 sec) and dalteparin (68 +/- 7 sec) groups with no detectable anti-Xa activity at baseline. Minutes after IV administration of enoxaparin and dalteparin, the mean Hemonox-CT increased to 171 +/- 60 sec and 214 +/- 70 sec for both groups, respectively. UFH induced a higher Hemonox-CT response (800 +/- 243 sec). At all time points, Hemonox-CT was higher than the ACT. Peak Hemonox-CT was associated with a therapeutic anti-Xa activity ranging from 0.50 to 1.35 U/ml (mean 0.89 U/ml) for the enoxaparin group and 0.69 to 1.48 U/ml (mean 0.91 U/ml) for the dalteparin group. After reaching peak levels, there was a gradual and parallel decline in Hemonox-CT and anti-Xa activity. The enoxaparin and dalteparin-treated patients successfully underwent PCI without major hemorrhagic complications. The Hemonox-CT has better sensitivity to both enoxaparin and dalteparin than does the ACT. Also, Hemonox-CT correlates with anti-Xa activity after IV administration. Hemonox-CT may become an important tool to monitor the anticoagulation effects of low-molecular weight heparin during PCI. Additional studies are needed to determine the target Hemonox-CT.