Superior vena cava (SVC) obstruction is associated with the gradual development of venous collaterals. We present a rare form of systemic-to-pulmonary subpleural collateral pathway that developed in the bridging subpleural pulmonary veins in a 54-year-old woman with complete SVC obstruction. This uncommon collateral pathway represents a rare form of acquired right-to-left shunt due to previous pleural adhesions with an increased risk of stroke due to right-to-left venous shunting, which requires lifelong anticoagulation.
*Collateral Circulation/physiology ; Female ; Humans ; Middle Aged ; Multidetector Computed Tomography ; Phlebography/methods ; Pulmonary Veins/physiopathology/*radiography ; Stroke/complications ; Superior Vena Cava Syndrome/physiopathology/*radiography ; Veins/physiopathology