When Anticoagulation Backfires - Heparin-Induced Thrombocytopenia and Acute Stent Thrombosis following Endovascular Therapy for Deep Vein Thrombosis: A Case Report.

We report a rare case of heparin-induced thrombocytopenia with thrombosis (HITT) following treatment for May-Thurner syndrome complicated by deep vein thrombosis (DVT), which resulted in venous stent thrombosis. A 27-year-old male with acute left lower-limb DVT successfully underwent thrombolysis and stenting for May-Thurner syndrome. However, the patient developed recurrent thrombosis and thrombocytopenia 3 days post-procedure. HITT was confirmed by a positive antiplatelet factor 4-heparin antibody test. After discontinuing heparin, the patient was successfully treated with fondaparinux, followed by repeat thrombectomy and thrombolysis, and then transitioned to warfarin. This is the second reported case of venous stent thrombosis due to HITT in May-Thurner syndrome. This case underscores the importance of early recognition and prompt management of HITT using alternative anticoagulants like fondaparinux to prevent complications such as venous limb gangrene. Further randomized controlled trials are required to evaluate the safety and efficacy of fondaparinux in HITT.