Aatrox/Devourer Bug

So when playing Aatrox in a custom game I had noticed that sometimes his W would not go off when using sated devourer. If the Sated Passive would activate Aatrox's W it will not heal him and I believe the Blood Price damage will not be applied. Now this is not always. sometimes it would apply and the animation would go off but about half the time it will glitch out and not work properly. Looking into this would be of great help. Thanks!