Which syndrome is specifically caused by obstruction of the left common iliac vein due to external compression?

May-Thurner syndrome is specifically characterized by the obstruction of the left common iliac vein, primarily due to external compression from the overlying right common iliac artery. This anatomical relationship leads to an increased risk of venous thrombosis in the left lower extremity.

In a healthy anatomy, blood flows from the legs back to the heart through the iliac veins, and any obstruction can disrupt this flow, often presenting with symptoms such as swelling, pain, or even more severe complications like deep vein thrombosis. May-Thurner syndrome highlights the importance of anatomical relationships in venous pathology, particularly the compression by the right common iliac artery leading to left common iliac vein thrombosis.

Other options do not describe this specific type of obstruction: Iliac vein obstruction syndrome is a broader term that does not specify the cause as May-Thurner syndrome does. Superior vena cava syndrome relates to obstruction of blood flow in the superior vena cava, typically due to tumors or thrombosis in the chest. Marfan syndrome is a genetic disorder affecting connective tissue and does not pertain to venous obstruction in this context.