May-Thurner syndrome (Iliac vein compression syndrome)

May-Thurner syndrome (Iliac vein compression syndrome)

May-Thurner syndrome denotes iliac vein compression by the crossing iliac artery at the iliocaval junction [1]. Usually it is the left iliac vein which is compressed by the right iliac artery. The compression increases the risk of deep vein thrombosis. Other names for the syndrome are iliac vein compression syndrome and Cockett syndrome [2]. The obstruction may cause varicosities in the affected limb and ulcers due to chronic venous stasis. The pulsations of the overlying artery causes intimal hypertrophy of the vein which adds to the severity of the obstruction. Some reports show that deep vein thrombosis occurs three to eight times more commonly on the left side. The original report was from May R and Thurner J in 1957 [1]. May-Thurner syndrome should be thought of in the differential diagnosis of edema of the left leg and the diagnosis can be confirmed by venography.

A report of right sided Cockett syndrome was described by Bert Du Pont, Jurgen Verbist, Wouter Van den Eynde and Patrick Peeters [2]. According to the authors, Cockett and Thomas described iliac vein compression syndrome and named Cockett’s syndrome in 1965. It was seen on the left side and mostly in women during second to fourth decade. The patient presented by Bert Du Pont et al had a non-complicated right sided Cockett’s syndrome which was successfully treated with balloon dilatation and stenting of right common iliac vein. Patient improved and was fine at six month follow up.

Since May-Thurner syndrome is a progressive disease, surgical options like vein patch angioplasty and repositioning of the iliac artery have been tried in the past. Implantation of a self expanding stent in the iliac vein is another option as described above.

Jiasheng Xu, Yujun Liu and Weimin Zhou reported mid term and long term data of 412 patients with Cockett syndrome [3]. Of these 231 had acute left iliac femoral vein thrombosis while 181 had chronic venous insufficiency. Endovascular treatment with venous stenting had good mid term and long term results. Follow up period ranged from 3 months to 8 years. Eighty nine patients who had valvular incompetence of left superficial femoral vein needed a second stage femoral valve repair.


  1. May R, Thurner J. The cause of the predominantly sinistral occurrence of thrombosis of the pelvic veins. Angiology. 1957;8:419-27.
  2. Bert Du Pont, Jurgen Verbist, Wouter Van den Eynde, Patrick Peeters. Right-sided Cockett’s syndrome. Acta Chir Belg. 2016 Apr;116(2):114-8.
  3. Jiasheng Xu, Yujun Liu, Weimin Zhou. Mid-and long-term efficacy of endovascular-based procedures for Cockett syndrome. Sci Rep. 2018 Aug 14;8(1):12145.