Treatment options in heparin-induced thrombocytopenia

Abstract

First-line therapies for HIT are argatroban or lepirudin. Patient-specific factors determine which drug should be used, and taking advantage of their differences allows effective anticoagulation with minimal risk of bleeding. Bivalirudin and fondaparinux require further study before they can be recommended. Once proven well tolerated and effective for treating thrombosis, these new oral anticoagulants should next be studied for treating HIT.

Heparin-Induced Thrombocytopenia

“…[101][102][103][104][105] The synthetic heparin pentasaccharide, fondaparinux, has been shown to be useful for the management of patients with HIT through several small published case series and is gaining favor. [106][107][108][109] The LMWHs can cross-react with most HIT antibodies and are contraindicated for use in patients with HIT. 27,110,111 Vitamin K antagonists (VKAs) are recommended for longterm treatment of HIT-associated thrombosis.…”

“…[114][115][116] There is emerging evidence that the newly developed small molecule anticoagulants including apixaban, dabigatran, edoxaban, otamixaban, and rivaroxaban may become new immediate and long-term treatment options for thrombosis in patients with HIT. 109 …”

Use of the Chromogenic Factor X Assay in Patients Transitioning from Argatroban to Warfarin Therapy

“…Heparin‐induced thrombocytopenia (HIT) occurs in 0.5–5% of patients who are treated with heparin and typically manifests as a significant decrease in platelet count 5–10 days after heparin exposure . This hypercoagulable state occurs when a patient produces antibodies to heparin–platelet factor 4 (PF4) complexes that form when heparin is administered . The heparin‐PF4 antibodies bind to the FcγIIA receptor on platelet surfaces, which leads to platelet activation, aggregation, and consumption and ultimately to thrombocytopenia .…”

“…In addition to thrombocytopenia and thrombosis, patients may also present with skin necrosis or an acute systemic allergic reaction . Due to the high risk of thrombosis when HIT is strongly suspected or confirmed, it is recommended that patients receive therapeutic anticoagulation with a nonheparin parenteral anticoagulant to prevent clot formation and/or extension, as well as other complications that may arise such as necrotic skin lesions or anaphylaxis . Current guidelines recommend continuing the nonheparin parenteral anticoagulant until platelet counts recover to 150 x 10 3 /mm 3 or have returned to baseline .…”

“…Current guidelines recommend continuing the nonheparin parenteral anticoagulant until platelet counts recover to 150 x 10 3 /mm 3 or have returned to baseline . Once platelet counts have recovered, the patient should receive therapy with the nonheparin parenteral anticoagulant overlapping with oral warfarin for a minimum of 5 days and until a therapeutic international normalized ratio (INR) has been acheived …”