Comparison of Bivalirudin and Argatroban for the Management of Heparin‐Induced Thrombocytopenia

STUDY OBJECTIVES: To compare the effectiveness of bivalirudin and argatroban in achieving anticoagulation goals and to compare clinical outcomes assessing the safety and efficacy in patients with known or suspected heparin-induced thrombocytopenia (HIT). DESIGN: Single-center, retrospective analysis. SETTING: Large tertiary care academic medical center. PATIENTS: A total of 138 adults who received either bivalirudin (92 patients) or argatroban (46 patients) for at least 24 hours for known or suspected HIT between January 2007 and July 2008. MEASUREMENTS AND MAIN RESULTS. Data regarding demographics, direct thrombin inhibitor (DTI) dosing and monitoring, and related clinical outcomes were collected; statistical analysis was performed to compare results for patients receiving bivalirudin versus those receiving argatroban. Duration of DTI use ranged from 24-658 hours. At the time of DTI initiation, 108 patients (78%) were in an intensive care unit, with the highest proportion (61/138 [44%]) in the cardiothoracic surgery intensive care unit. The median (interquartile range [IQR]) DTI doses at the time of first reaching therapeutic goal were bivalirudin 0.06 mg/kg/hour (0.04-0.08 mg/kg/hr) and argatroban 1.0 μg/kg/minute (0.5-2.0 μg/kg/min). The median percentage of activated partial thromboplastin time (aPTT) values within therapeutic range while patients were receiving DTI therapy were similar for bivalirudin and argatroban (75% and 70%, respectively, p=0.238). A greater percentage of aPTT values were supratherapeutic with argatroban versus bivalirudin treatment (18% vs 8%, p=0.046). Median time to therapeutic goal was similar for bivalirudin (5.50 hrs [IQR 4-14.5 hrs]) and argatroban (5.75 hrs [IQR 3-17.7 hrs], p=0.499). New thromboembolic events occurred in seven patients (8%) receiving bivalirudin and two (4%) receiving argatroban (p=0.718). Bleeding events occurred at similar rates in both groups (9% for bivalirudin vs 11% for argatroban, p>0.999). CONCLUSIONS: Bivalirudin and argatroban were similar in achieving and maintaining therapeutic anticoagulation goals, clinical outcomes, and safety. This study suggests that bivalirudin represents an alternative in the management of HIT, but prospective studies are needed.