Management of Venous Thromboembolism in a Patient with Alteplase Allergy and Heparin-Induced Thrombocytopenia: A Case Report

Purpose: To review anticoagulation and thrombolytic options for venous thromboembolism (VTE), highlighting common allergies and alternative therapies. We highlight a unique case and management of VTE in a patient with heparin-induced thrombocytopenia (HIT) and alteplase (tissue plasminogen activator [t-PA]) allergy.

Materials and Methods: We present a 67-year-old woman with a history of myocardial infarction status post multiple stents who presented to the emergency department with right lower extremity edema and erythema as well as abdominal discomfort. She was found to have infrarenal abdominal aorta and right common iliac artery aneurysms as well as an arteriovenous fistula between the right common iliac artery and vein. Additionally, there was extensive clot in the right common femoral vein. Therapy was led by intravenous heparin. However, the platelet count progressively dropped. The HIT panel returned positive. Heparin was stopped. Interventional radiology (IR)–guided right lower extremity venogram, thrombolysis, and thrombectomy were performed with infusion of 10 mg of t-PA. Not long after infusion of alteplase, the patient went into respiratory failure and became febrile, tachycardic, tachypneic, hypoxic, and hypertensive. Computed tomography angiography of the chest revealed a segmental pulmonary embolus and flash pulmonary edema, indicating anaphylactic allergic reaction to t-PA infusion.

Results: The patient was subsequently intubated, treated with antiallergic medication regimen, stabilized, and extubated 2 days later. IR thrombectomy removed most of the clot. Hematology/oncology advised on a comprehensive anticoagulation regimen. Double antiplatelet therapy was initiated. The patient was started on argatroban as a bridge to rivaroxaban. Alternatives to alteplase were considered such as streptokinase and urokinase, but mechanical thrombectomy was sufficient in this patient.

Conclusions: A thorough understanding of the commonly used anticoagulants and thrombolytics is an essential part of every IR practice. Often, though, a patient will be unable to receive the commonly prescribed medications and will require alternative treatment. Interventional radiologists therefore benefit from a review of important alternative anticoagulation and thrombolytic therapies.