More than 1,500 people were injured after panic swept through the crowd during the viewing of the match, which Juve lost 4-1 to Real Madrid.
A statement from the Turin prefect claimed that the crowd was "taken by panic and by the psychosis of a terror attack", amid fears that a loud noise had been caused by an attack of some kind.
Three people were left seriously injured, and it has now been confirmed that Pioletti has passed away. She was 38.
It is understood that she suffered a heart attack after her thorax was squeezed during the stampede, leading to irreversible brain injuries.
Her family have subsequently authorised doctors to switch off the life support machines that had been keeping her alive.