Last week we documented that the heartworms live mostly in the right side heart chambers. That alone could compromise the heart function immensely. The heart just can’t get enough blood out into the circulation. This means that many organs further down the line are being starved of an adequate supply of blood and therefore do not get enough oxygen (the blood carries the oxygen to all the organs).
Besides the fact that a bundle of worms in the heart takes up space in the heart (space needed for specific volumes of blood), these worms can entangle themselves in the heart valves and therefore impede the mechanical aspect of the heart’s function.
Of course, all of this becomes worse, if the worms are actually and physically constraining the flow of the blood from the heart to the lungs. You can imagine how the animal would be panting (increase in the breathing rate) trying to get more oxygen into the system.
But not only the lungs are messed up. Some of these worms can actually get into the large blood vessels related to the liver! The liver’s functions begin to collapse. Jaundice (yellowing) develops.
The abdomen swells due to increased fluid there. The animal can become anaemic especially if it is losing blood via the faeces. I can tell you that once the liver is compromised the prognosis looks very bleak. In fact, the animal could die in a couple of days. The disturbing consideration here is that the veterinarian seeing these symptoms would logically be tempted to address the issues relating to the destabilization of the liver function, since the symptoms are associated with liver damage. So let this be a lesson to all: if the abdomen swells with fluid (Ascites), check for heartworms. It might not be heartworms, but have it checked nevertheless. The test is completed in minutes.
It is better to go this route than to later curse ourselves (owner and vet) for not having recognized heartworm as a possible cause (for the weakening of the animal) in the differential diagnosis.
Anyway, enough lecturing. This story I was developing with the liver was actually not the norm. Acute (sudden) ailment with an immediately obvious set of symptoms is not usually the way the heartworm infection usually proceeds.
Let’s look at the symptoms of a heartworm infection. As I said last week, this is an insidious (gradual) disease. It sneakily invades the dog/cat, and it sneakily progresses into a full-blown sickness.
The first signs do not appear until many months, even a year (even years, according to some cases cited in the literature) after the infection by the mosquito has taken place. No wonder the veterinarian could mistake it for another ailment.
I’ll share with you the signs that impact upon me the most, those things that make me think of heartworm!
i)Any dog that comes from Courida Park/Lower East Coast/and immediate environs. Of course, there are other geographic areas (eg New Amsterdam and the Corentyne where heartworm infections of dogs abound.
ii) Emaciation – especially when I know that the dog is being fed well and is being dewormed regularly. The weight lost is often accompanied by an abdomen that is a bit (almost imperceptibly) swollen and a rib cage where you can actually see the ribs.
iii) A cough! Not a rasping, gasping, throaty, spasmic cough. It is a soft yet deep cough; not as if something is stuck in the throat. Rather, it might best be compared with the cough that might be emitted if one has a slight sore throat.
iv) My next question when I hear about the cough is whether the dog gets tired easily, even after minimal exertion. Apathy and listlessness are always present.
v) The other symptoms come much later:
– Vomiting blood
– Severely laboured breathing (The vets call it ‘respiratory distress’ – you can see our profession has big, confusing words too).
vi) Of course, the clincher is the laboratory examination of the blood. There can be no dispute as to the presence of heartworm if the test is carried out correctly.
Next week we’ll deal with this lab test because it is not as straightforward as it sounds.
Please implement disease preventative measures (vaccinations, routine dewormings, monthly anti-heartworm medication, etc) and adopt-a-pet from the GSPCA’s Animal Clinic and Shelter at Robb Street and Orange Walk, if you have the wherewithal to care well for the animals. Do not stray your unwanted pets, take them to the GSPCA Clinic and Shelter instead. If you see anyone being cruel to an animal, get in touch with the Clinic and Shelter by calling 226-4237.
