I'm so sorry to hear Sammy is not responding well. I sure hope we get a good uppydate today.

{{{hugs}}}

I know this doesn't help you and Sammy right now, but it might help someone else. Feline heartworm is becoming more and more prevalent. Everytime I go to the vet I see ads and pamphlets all over the place for Revolution which is really kind of a "cure all" type medicine. You put it on the scruff of their neck once a month and it prevents fleas, several parasites and also heartworms. And yes, heartworms are a problem even for inside only kitties. If you check out the Revolution website you'll find much more information than I've got here. So, hopefully this will not be all in vain for Sammy if even one kitty is saved because their meowmy heard about the threat of heartworm and the Revolution to cure it.

Come on Sammy, please get better.