May Thurner syndrome: description of a case with unusual clinical onset.

May-Thurner syndrome (MTS) is a congenital vascular alteration that is part of a restricted category of very rare vascular syndromes that have in common the compression of an arterial or venous vessel. MTS, first described in 1957, is due to compression of the left common iliac vein against the lumbar spine by the adjacent common iliac artery. It can cause chronic thrombosis of the left lower limb and can give edema, pain, claudication, thrombophlebitis, and, in severe cases, pulmonary embolism. Color Doppler and duplex Doppler ultrasound allow us to easily locate the deep vein thrombosis, to measure its extension, and to highlight the vascular changes typical of MTS: compression and consequent hypertension of the left common iliac vein. The therapy depends on the degree of venous stasis and on the presence of venous thrombosis; generally, it consists of the administration of short- or long-term anticoagulant and thrombolytic drugs. In cases of severe stenosis of the left common iliac vein, the first-choice treatment consists of positioning a vascular stent, which resolves compression and significantly reduces chronic thrombotic episodes. We describe a case of MTS with an unusual clinical onset with pulmonary embolism.