Blood clots are the most significant risk of treatment, and some of them can be fatal, which is why we assess our candidates while we're treating them. We do what's called staging to see how severe we feel the infestation is and the worm burden, as the disease is impacted by the number of worms that the dog may have. And it's an educated guess, frankly. We're looking at X-rays to look at changes in the lungs and at blood work to make sure the liver and kidneys aren't having any problems because this is a disease that affects the lungs’ vessels, and hence, perfusion to the organs and things like that. We need to assess all of that stuff, and once we get to that staging, we can make an educated guess as to how severe and advanced this heartworm disease might be and how well or not well a dog might do through treatments.

Death is one of the most significant complications. These dogs can go into respiratory distress syndrome. Also, these worms are 12 inches long. Pieces of them can break off while the dog is running and playing, and they form a blood clot that can go to the lungs or other parts of the body. And sometimes, even often, it's fatal. Fatality is one of the worst complications. Even with treatment, the dog will often develop pulmonary hypertension, which eventually leads to some right-sided heart failure.

Because dogs tend not to show any signs until they have a very mature, advanced infestation. By that point, they often have had damage to their heart and lungs, so this is a disease we want to catch early before they have signs. We want to screen for this disease every year. If a dog has had heartworm for years, they're more apt to not do well through treatment because they've had this infestation for so long. There's often a lot of permanent damage to their lungs and heart.

In some cases, the damage is reversible. Usually, the earlier that you catch it, the better, but the more prolonged the infestation, the more apt the dog is to have complications during treatment, which can be fatal, quite frankly. And also, they can develop some permanent lung changes that lead to heart problems later on.

Usually, I'm going to run a test called an ELISA test. It's a blood test that we run here in the office. It is screening for adult female worms, which are 90% of the worms that dogs are infested with, if not more. This test is also recommended yearly because it screens for some of the tick-borne pathogens, Lyme disease, Ehrlichia, and anaplasmosis, which are also essential to screen for in your dog. If the dog is positive, we will also continue to look at the blood, looking for baby heartworms to confirm that diagnosis. We look in the microscope for those, and you can see them wiggling. They look like tiny, wiggly worms.

We don't always want to just throw medications at animals. We want to consider things like how they are at home. Are they eating too much? Could they lose some weight? Do they have arthritis? If they lose some weight, that will really help a lot.

ASPCA has a poison control hotline that you can call. You would need to know what the dog ingested. You can't just call them with a random question and say, "Hey, I think my dog ..." Instead, you’ll want to say, "Hey, my dog just ate Devon-CON rat poison," or whatever it is, and they can tell you exactly what the active ingredient is and what you need to do. Again, your veterinarian will have to be part of that solution in 99.9% of the cases. But to at least give you some immediate information about how to handle things, and what you may or may not experience with that dog, what your dog will experience, calling the ASPCA hotline is probably the first step.