May-Thurner Syndrome With Pulmonary Embolism as the First Presentation Rather Than Deep Vein Thrombosis.

May-Thurner syndrome (MTS) is a rare disease that causes deep vein thrombosis (DVT) in young females (age 20 to 50). DVT is caused by mechanical obstruction of the left common iliac vein by the right common iliac artery resulting in stasis rather than a primary hypercoagulable state. Although MTS is found in 22% of cadavers, it causes <5% of lower extremity venous disorder. Greater than 70% compression is needed to cause DVT. MTS patients usually present with acute left leg edema. Many cases are recurrent with a past workup negative for other etiologies of DVT or pulmonary embolism (PE). Cases rarely present as PE rather than DVT. We present a case of this syndrome at a younger-than-typical age with PE as the first presentation. Femoral stick venogram is the gold standard for diagnosing MTS as therapeutic procedures can be done concurrently. Anticoagulation therapy alone is insufficient to prevent recurrence.