Heart Failure Following Sinus Venosus Defect Closure in a Patient With Vein of Galen Malformation

This case concerns an 18-month-old with masked congestive heart failure (CHF) from an unrepaired vein of Galen malformation and superior sinus venosus defect who progressed to severe, refractory CHF following superior sinus venosus defect repair. Partial transvenous coil embolization of a very-high-risk vein of Galen malformation resolved CHF symptoms. (Level of Difficulty: Advanced.).