ENDOVASCULAR RECONSTRUCTION FOLLOWING IVC AND BILATERAL LOWER EXTREMITY THROMBOSIS IN AN ADOLESCENT

ABSTRACT

Background: Inferior Vena Cava (IVC) abnormalities are a risk factor for the development of lower extremity deep vein thrombosis (DVT). Abnormalities can be congenital or acquired and include IVC atresia, a rare and lesser known problem for adolescents. Adolescents with IVC atresia are at high risk for DVT's that are often refractory to standard anticoagulation methods, including thrombolysis. Objectives: The purpose of this report is to highlight a young patient with extensive lower extremity DVT in the setting of underlying IVC atresia and describe the complex care required. The patient is a 16-year-old with a history of venous insufficiency who presented with low back pain and lower extremity swelling. Thrombotic risk factors included factor V Leiden heterozygosity, oral contraceptive use, and recent COVID-19 vaccination. An MRI completed by the orthopedist for back pain was concerning for abnormal signal in the IVC as well as an IVC aneurysm. A contrast enhanced CT was obtained and demonstrated atresia of the suprarenal IVC, subacute thrombosis of the infrarenal IVC along with an IVC aneurysm, and subacute thrombosis of the bilateral iliac veins. Design/Method: A retrospective chart review of the patient's initial presentation, imaging, and treatments was conducted along with a review of the literature involving similar cases. Results: Initial treatment was intravenous heparin and t-PA mediated thrombolysis. After overnight thrombolysis, venography revealed significant clot lysis;thus, she was transitioned to subcutaneous enoxaparin and discharged home with therapeutic anti-Xa levels. Follow up imaging 3 days later revealed recurrent thrombosis of the deep veins in both lower extremities. She was readmitted, placed on intravenous heparin, and received catheter directed t-PA thrombolysis. Clot burden was so extensive it was further reduced using Angio jet thrombectomy and balloon angioplasty. Because the recurrent clots were attributed to lack of outflow from the underlying IVC atresia, interventional radiology completed endovascular reconstruction of the IVC. She then transitioned from intravenous heparin to therapeutic enoxaparin, clopidogrel, and aspirin. At three month follow up, imaging was negative for clot and her vasculature was widely patent. Conclusion: Pediatric patients with bilateral lower extremity DVTs are uncommon and underlying IVC abnormalities should be considered in the evaluation. Optimal treatment strategies are evolving and include aggressive anticoagulation and endovascular reconstruction.