Mechanical Thrombectomy of Subacute Idiopathic Inferior Vena Cava Thrombus via the INARI ClotTriever

Purpose: Inferior vena cava (IVC) thrombosis is a rare disease often resulting from the presence of an IVC filter but can also present de novo because of hypercoagulable states or IVC pathology. The population-based incidence of vena cava thrombosis is 1.7 in 100,000, and pulmonary emboli occur in 12% of these patients. Although anticoagulation is considered the mainstay of therapy, newer endovascular techniques have become more widely adopted treatment adjuncts in recent years. We present a case of a large IVC thrombosis in the setting of no known risk factors treated successfully with mechanical thrombectomy.

Materials and Methods: A 34-year-old female smoker with no medical history presented to the emergency department after a syncopal episode and spontaneous left lower quadrant pain. One month prior, she had hemoptysis, which was attributed to bronchitis. Computed tomography (CT) of the abdomen and pelvis demonstrated rectus sheath hematoma as well as a large IVC thrombus extending from the suprarenal IVC to the right external iliac vein. Additionally, CT pulmonary angiogram demonstrated bilateral pulmonary emboli with associated pulmonary wedge infarcts. Interventional radiology was consulted for evaluation and treatment of the IVC thrombus.

Results: A venogram confirmed the presence of a 14-cm IVC thrombus. FlowTriever disks were deployed through a left femoral 12-Fr sheath into the IVC just below the right atrium above the level of the thrombus. Under fluoroscopic guidance through a 16-Fr right femoral sheath, multiple passes were made with the ClotTriever, removing large subacute clot burden from the vessel. After mechanical thrombectomy, repeat venogram demonstrated complete clearance of clot. Repeat inferior vena cavagram with pulmonary artery pressures was performed 6 weeks later demonstrating a widely patent IVC and normal pulmonary arterial pressures.

Conclusions: Although systemic anticoagulation therapy is fundamental in controlling propagation of large-vessel thrombosis, not all patients are optimal candidates based on individual risk profiles. Therefore, recent evolution of endovascular treatment options such as catheter-directed thrombolysis and mechanical thrombectomy provides clinicians additional tools for personalized care. The role of mechanical thrombectomy for caval occlusion is an emerging topic, and future studies are necessary to further delineate indications for the best long-term outcomes.