Abstract
This case report detailed a rare case of upper limb venous outflow obstruction due to primary subclavian vein valve hypertrophy in a 26-year-old male. Misdiagnosed initially, the condition was identified through advanced Doppler ultrasound and Computed Tomography Venography (CTV) Endovascular treatment using Wallstent stents effectively resolved the obstruction, preserving collateral venous circulations. This case highlights the importance of combined colour Doppler ultrasonography for diagnosing unusual venous obstructions and demonstrates the potential of endovascular treatments in managing rare venous conditions.