[Unexpected findings during surgery for interventricular communication and for banding of the pulmonary artery in the infant and child].

While the authors recognise the difficulty of obtaining a complete picture of the lesion in certain types of ventricular shunt with pulmonary hypertension, they emphasise the importance of a precise diagnosis, which may modify the medical treatment and the decision to operate. Conditions may nevertheless be found by surprise at operation, and lead to a modification of the planned action.