Background: May-Thurner Syndrome (MTS) is a rare vascular condition where the left common iliac vein is compressed between the right common iliac artery and the spine. We report a case of a patient with a left-sided inferior vena cava and right-sided May-Thurner syndrome. He had recent symptomatic COVID infection despite vaccination (Janssen).

Case: A 28-year-old male presented with right lower extremity pain and swelling for three weeks. A duplex ultrasound was performed revealing iliofemoral deep vein thrombosis. Pharmacomechanical thrombectomy with ultrasound assisted thrombolysis was performed with subsequent femoral venogram and angioplasty of the right common iliac vein.

Conclusion: May-Thurner Syndrome often remains underdiagnosed due to the chronic nature of the disease process. The presence of a left-sided IVC leading to right sided MTS with recent COVID-19 infection (and vaccination) was a unique feature of this case. May-Thurner Syndrome should be considered in the differential diagnosis of those present with DVTs or symptoms of venous hypertension.