Seroma formation after modified Blalock-Taussig shunt which caused shock due to pulmonary vein compression.

Seroma formation is a relatively rare complication seen after a modified Blalock-Taussig shunt. Herein, we report a rare case of seroma formation on the posterior aspect of the left atrium without it touching the graft, and presenting with shock, due to pulmonary vein compression.