Abstract Number: PB1419
Meeting: ISTH 2020 Congress
Background: Heparin-induced thrombocytopenia (HIT) is a severe adverse reaction to heparin treatment caused by IgG antibodies that recognize platelet factor 4/heparin complexes (PF4/H) associated with an increased risk of thrombosis. When HIT is suspected, heparin must be stopped immediately and replaced by another anticoagulant such as danaparoid sodium or argatroban. Their use during cardiac surgery is associated to an increased risk of bleeding and/or thrombosis. Therapeutic plasma exchange (TPE) has been proposed to remove HIT antibodies quickly to allow heparin use during surgery.
Aims: We report 2 cases of patients who underwent repeated TPE, achieving negative anti-PF4/H and allowing cardiac surgery with heparin for one of them.
Methods: Testing for HIT antibodies was performed using anti-PF4/heparin IgG-specific EIA (Zymutest HIA IgG, Hyphen Biomed) and heparin-induced platelet activation (HIPA) assay.
Results: A 36-year-old woman received veno-arterial extracorporeal membrane oxygenation (ECMO) support for an acute exacerbation of pulmonary fibrosis. She developed thrombocytopenia on day 10 of anticoagulation with unfractionated heparin (UFH) (nadir 29G/L) and a deep femoral vein thrombosis. EIA was strongly positive (2609 mU.OD), confirmed by HIPA assay. Five TPE were performed to remove anti-HLA, which also achieved negative anti-PF4/H (125 mU.DO) and HIPA on the day of lung transplantation.
A 63-year-old patient was hospitalized for cardiogenic shock complicated with multiple organ failure and required ECMO. He developed thrombocytopenia on day 12 of anticoagulation with UFH (nadir 15G/L) and thrombosis in the ECMO circuit. HIT was confirmed by strongly positive anti-PF4/H (2291 mU.DO) and HIPA. Anticoagulation with argatroban was initiated. Because surgical treatment of interventricular communication was required, 4 TPE sessions were performed and achieved negative anti-PF4/H (481 mU.OD pre-surgery). The patient underwent surgery with usual UFH doses, without thrombotic complication.
Conclusions: These 2 cases confirm that TPE is safe to remove HIT antibodies and allow heparin use during surgery in the acute phase of HIT.
[IgG-specific anti-PF4/H EIA and HIPA test results in relation to 5 TPE]
[IgG-specific anti-PF4/H EIA and HIPA test results in relation to 4 TPE]
To cite this abstract in AMA style:
Cavalié C, Gendron N, Provenchère S, Sonneville R, Kantor E, Faille D, Ajzenberg N. Therapeutic Plasma Exchange in the Pre-Operative Management of Acute HIT [abstract]. Res Pract Thromb Haemost. 2020; 4 (Suppl 1). https://abstracts.isth.org/abstract/therapeutic-plasma-exchange-in-the-pre-operative-management-of-acute-hit/. Accessed March 21, 2024.« Back to ISTH 2020 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/therapeutic-plasma-exchange-in-the-pre-operative-management-of-acute-hit/