May-Thurner syndrome

May–Thurner syndrome (MTS), also known as the iliac vein compression syndrome, is a condition in which compression of the common venous outflow tract of the left lower extremity may cause discomfort, swelling, pain or clots (deep venous thrombosis) in the iliofemoral veins. Specifically, the problem is due to left common iliac vein compression by the overlying right common iliac artery. [Source: Wikipedia ]

Iliac vein compression syndrome
May Cause
Inferior vena cava obstruction
Venous occlusion