I do not give my cat heart worm prophylactics. In part because she is strictly indoors. And she has adverse (though unproveable) reactions to vaccines, like increase in FHS symptons (twitching skin, biting her fur even though nothing is biting her). Also, from what I've very briefly read, cats are fairly resistant to heartworms/mosquitoes.
I *might* consider giving her something to prevent Fleas, she seemed to have a minor episode last year. I'll have to see.
Revolution is a highly toxic heavy hitter when it comes to flea and parasite prevention. When administered, it enters and stays in the bloodstream as opposed to Advantage which sits on the skin. I would not use Revolution every month, but use only as a means of dealing with an infestation, but depending on the severity, Advantage might be sufficient.