May Thurner Syndrome

Abstract

A 54-year-old man with an unremarkable past medical history presented with a four-hour history of severe left lower extremity pain and swelling. He arrived earlier in the same day after a 15-hour transpacific flight. On physical exam, his left leg was edematous and demonstrated palpable pulses. His sensation, strength, and range of motion were preserved, but his left lower extremity was markedly tender. Duplex ultrasound evaluation demonstrated a nonocclusive thrombus in the superficial femoral vein extending to the common femoral vein. Given the severity of the patient’s symptoms, he was evaluated by interventional radiology for ultrasound-assisted thrombolysis. Venography revealed occlusion of the left common iliac vein with numerous small collaterals consistent with May Thurner syndrome (Figure 1). Balloon venoplasty yielded improved flow, and the high grade stenosis of the left common iliac vein demonstrated prompt wide open forward flow to the IVC following stenting (Figure 2). The patient tolerated the procedure well and his symptoms resolved subsequently. May Thurner syndrome, also known as iliac vein compression syndrome, is an underdiagnosed venous disease caused by the compression of the left iliac vein by the right iliac artery, which predisposes to venous insufficiency and thrombosis. Treatment with systemic anticoagulation alone is often inadequate, and clot lysis followed by stent placement is usually necessary to correct the underlying anatomic cause. This entity should be particularly considered in the differential diagnosis of young patients with recurrent DVT.