Clinical experience with combined treatment of thrombin inhibitors and GPIIb/IIIa inhibitors in patients with HIT.

Despite the use of potent anticoagulants such as r-hirudin and argatroban, the morbidity/mortality of heparin-induced thrombocytopenia (HIT) patients remains high. In the last several months, we have treated three HIT-positive patients with a combined therapy of thrombin inhibitor and GPIIb/IIIa inhibitor when treatment with thrombin inhibitor alone failed to alleviate acute thrombosis. Combination therapies included r-hirudin (Refludan) with tirofiban (Aggrastat) or argatroban (Novastan) with ReoPro. A reduced dose of the thrombin inhibitor with the standard dose of the antiplatelet drug was the dosing regimen used. In all cases, there was no overt bleeding that required intervention and all patients had improved or fully recovered. This first report of the use of GPIIb/IIIa inhibitors with thrombin inhibitors in HIT patients with active thrombosis suggests that this combined therapy may be more effective than thrombin inhibitor treatment alone. The data from these three cases warrant testing of this therapeutic regimen in larger studies to determine optimal dosing strategies.