CIRSE standards of practice guidelines on iliocaval stenting.

Chronic venous insufficiency (CVI) as an advanced stage of chronic venous disease is a common problem that occurs in approximately 1-5 % of the adult population. CVI has either a nonthrombotic (primary) or postthrombotic (secondary) cause involving reflux, obstruction, or a combination of both. The role of venous obstruction is increasingly recognized as a major cause of CVI, with obstructive lesions in the iliocaval segment being markedly more relevant than lesions at the levels of the crural and femoral veins. Approximately 70-80 % of iliac veins develop a variable degree of obstruction following an episode of acute deep venous thrombosis. Nonthrombotic iliac vein obstruction also known as May-Thurner or Cockett's syndrome is the most common cause of nonthrombotic iliac vein occlusion. While compression therapy is the basis of therapy in CVI, in many cases, venous recanalization or correction of obstructive iliac vein lesions may result in resolution of symptoms. This document reviews the current evidence on iliocaval vein recanalization and provides standards of practice for iliocaval stenting in primary and secondary causes of chronic venous disease.