Anatomy and Art

So, I knew from the beginning that Rocky had tested positive for heartworms.  He has been taking doxycycline to reduce the size of the worms for about a month now, as well as a preventative to keep him from getting any more, and on January 8th, we start the big scary part of the treatment, where he is injected with a drug containing arsenic into his back muscles near the heart to kill the now weakened worms.

The whole procedure sounds just awful for a dog to go through.  He’ll be sick for weeks, and have to be kept calm for more than a month to prevent his heart rate from elevating and pumping too many of the dying worms into the pulmonary artery at once and blocking blood flow.

The standard treatment seems to be one injection into one side of a dogs back on one day and then a second injection the next day into the other side of their back.  Then the dog has to be kept calm (often crated) for the following 4-6 weeks.  There is also an option to spread out some of the treatment by doing one injection, and then doing the two day sequence one month later.  This is generally considered safer because it decreases the amount of worms breaking up in the heart at one time.  But I have to question if it takes into account the danger of extending the time frame by a whole month that the dog can die from over excitement.

Some experts default to the 2 injection plan, only extending the treatment in severe cases.  Others, seem to feel like the 3 injection plan is always better because of the reduced volume going into the pulmonary artery at any single time.  To be honest, I’ve seen conflicting advice about the antibiotic portion of the treatment as well, and what can be done to assess the severity of the case.  I thought that this chart was helpful for looking at the basic symptoms that can be observed in the dog without any further testing.

I found that through the following link, which has a lot of good information.
http://www.heartwormsociety.org/pet-owner-resources/canine-heartworm.html

According to that, Rocky should be in pretty good shape and do well without spending an extra month cooped up and sick.  When I spoke to his vet about how healthy he seemed running around over Christmas out in the country, he said I’d *probably* be okay, and that the last thing he’d want to do is kill my dog.  So of course I’ve been studying up since then.  And I even made an appointment at a nearby emergency clinic for another blood test, which I hope isn’t offensive to the vet I’m working with, but their test was showing me elevated eosiniphils, and I think that I should be able to get some kind of count regarding larvae in the blood itself.  It’s still not a perfect view of how bad off he is, but I feel like it’s a diagnostic tool I’d like to factor into the 2 vs 3 injection decision.

Anyway, in all of my frustration to get good information, I wanted to go ahead and post as much as I’ve come to understand so far, and let anyone else looking know that the American Heartworm Society has really been the best source of information on the internet that I’ve found so far.

http://www.heartwormsociety.org/veterinary-resources/canine-guidelines.html

The Camino Animal Clinic has good information too and also a nice illustration of the heartworm cycle, and map of where heartworm is most prevalent in the United States.  It’s no surprise to see Austin, TX looking awfully red in that map.

http://www.caminoanimalclinic.com/canine-heartworm-disease/

With all of the really vague information and conflicting advice out there, I can’t be the only one trying to pick out the better sources out there.