A simple well-executed concept with good music and juicy effects.
You might consider adding a way to regain health, either slowly regenerating or as a collectable. Also, increase the space between waves, as jumping 2 lanes in such a short space is difficult. Alternatively, you could have the waves start slower, and increase in speed as the game progresses.
Had good fun with this one, but got no where near your score.
Good work, and good luck! :D