May-Thurner syndrome (MTS) is a condition characterised by compression of the left common iliac vein by the right common iliac artery and the anterior spine of the 5th lumbar vertebrae. Previously thought to be a rare condition, the prevalence of MTS is thought to be underreported. MTS can lead to significant morbidity in the form of chronic venous insufficiency, venous ulceration, lower limb swelling, venous claudication, deep-vein thrombosis, varicose veins, pelvic congestion syndrome, chronic pelvic pain and chronic post-thrombotic syndrome. It is a known risk factor for development of venous incompetence and varicose veins in adolescents and young adults. Furthermore, it is known to be an a causative factor in the development of unprovoked DVT in younger patients, however data on the risk of development of DVT in MTS patients has to date, been unavailable.~The pathogenesis of MTS is largely unknown and whilst the condition is known to be more prevalent in females, familial risk factors are largely unknown. To date, no studies have previously assessed the prevalence of MTS in relatives of those with the condition.
The aim is to assess the prevalence of May-Thurner syndrome in 1st-degree relatives of previously identified symptomatic patients.