The efficacy and safety of direct oral anticoagulants in the treatment of the acute phase of heparin-induced thrombocytopenia: A systematic review

PURPOSE: To investigate the safety and efficacy of direct oral anticoagulants (DOACs) in the treatment of the acute phase of heparin-induced thrombocytopenia (HIT). SUMMARY: A systematic review of the literature was conducted on PubMed, MEDLINE, Embase, and Web of Science Core Collection through July 2023. Search terms included "heparin-induced thrombocytopenia AND direct-oral-anticoagulants" in addition to a list of oral anticoagulants. Adult patients who used direct oral anticoagulants as the initial treatment for the acute phase of HIT were included. A total of 1,188 articles were initially identified, with 770 articles reviewed following removal of duplicates. Following the application of inclusion and exclusion criteria, 12 articles were ultimately included. Rivaroxaban was the most-utilized DOAC (28 patients), followed by apixaban (7 patients) and dabigatran (1 patient). All patients with thrombocytopenia demonstrated successful platelet recovery, with two patients presenting with normal platelet counts. One patient developed a deep venous thrombosis with no other new or recurrent thromboses. There were no reported clinically significant adverse events in any patient. Obstacles and deterrents to the use of the standards of care in the acute phase of HIT exist. Argatroban and bivalirudin require intravenous infusion and require close aPTT monitoring and dose adjustment. Fondaparinux requires injection and is contraindicated with body weight <50kg. DOACs would offer the novel ability for an oral treatment in the treatment of the acute phase HIT and allow for minimal monitoring and consistent dosing strategies. Therefore, DOACs are an intriguing choice for the treatment of the acute phase of HIT. CONCLUSION: Data from 12 publications and across 36 patients suggests that the use of DOACs in the acute phase of HIT may be a safe and efficacious treatment option with favorable ease of monitoring and management.