CONGESTIVE HEART FAILURE

By Bev Reeve

Kidney disease is quite common in elderly rats and the symptoms can often be mistaken for other ailments. For instance, kidney disease can cause fluid build-up in the lungs causing a rat to wheeze. And hind leg paralysis can be a common symptom of kidney disease.

A rat suffering from kidney disease will suffer chronic weight loss, its coat will look rough and in poor condition, it will urinate more frequently than usual. Kidney disease/failure cannot be cured but you can help to reduce the work of the kidneys (therefore alleviating the symptoms) by placing your rat onto a low protein/low salt diet. Another treatment that has been found to be very beneficial is Ipakitine powder. Usually prescribed to cats and dogs with heart problems, and to cats with kidney failure, a small pinch of the powder added to a treat once a day will help. Ipakitine binds together the fats in the diet and makes them bypass the kidneys. Therefore the kidneys have less work to do.

You may notice that your rat starts to walk as if it is wearing flippers on it's back feet, this weakness will grow until your rat can no longer use its back legs at all and will pull itself around by it’s front paws, while dragging the back paws.

If the cause of the hind leg paralysis is kidney disease, then the Ipakitine powder will help and as the pressure is taken off the kidneys, your rat should regain some use of his/her back legs.

However, in some cases, hind leg paralysis is caused by degeneration of the nerves (a condition called Degenerative Myelopathy) or arthritis and for this the treatment is one drop of Metacam per day. However, you should not attempt to treat your rat with Metacam until your vet has confirmed that it is Degenerative Myelopathy or arthritis causing the paralysis because if it is linked to kidney disease then the Metacam can actually make the kidneys worse.

Black faeces or worsening of the hind leg paralysis are the two main side effects of Metacam and if either is spotted you should stop giving the drug immediately. Luckily, stopping the Metacam will reverse the side effects quite quickly.

Once the hind legs are paralysed, it is rare that your rat will ever regain full use of them again, however it is not a sign that your rat is about to die. Extra care will be needed for a paralysed rat, they won't be able to hold food very well, clean their ears or wash their faces or hind quarters and will require you to do these things for them. Make sure they are not laying in their own urine, wash their hind quarters for them with a damp flannel, use a cotton bud to gently wipe excess wax from the ears (don't dig down), wash their faces for them and give them soft food that they can lap up from a shallow dish. Lower the water bottle so they can reach it from a sitting position.

There is no need to remove a rat with hind leg paralysis from it's own cage but you will need to redesign it so that your paralysed rat can reach everything it needs on the ground floor. Allow the other rats to still climb and move about as normal (i.e. don't remove ladders or take everything off of upper levels).

Symptoms of heart failure can include weakness or tiredness, wheezing, difficulty breathing and poor appetite. In severe cases, nose, mouth, tip of tail and toes can turn blue. The symptoms of CHF are often mistaken for myco. CHF can cause kidney failure.

Congestive Heart Failure can be either hypertrophic cardiomyopathy (in which the muscle-wall of the left ventricle thickens due to overwork, reducing the size of the chamber and leading to a stiff, inefficient pumping action) or dilated cardiomyopathy (an enlarged flabby heart). A rat with hypertrophic cardiomyopathy can get oedema (build up of fluid) in the lungs. Dilated cardiomyopathy often leads to oedema of the skin and sometimes around the abdomen.

The treatment for CHF is a low salt diet, a diuretic (a drug which reduces the build-up of fluid) such as Lasix and an ACE (Angiotensin-Converting Enzyme) inhibitor called Enalapril (brand names Enacard, Vasotec) which lowers the blood pressure and makes it easier for the heart to beat. If the rat is definitely suffering from dilated cardiomyopathy, the drug Cardoxin can be added to this list but Cardoxin MUST NOT be given to a rat with hypertrophic cardiomyopathy. Cardoxin helps the heart to beat stronger and could be fatal if given to a rat with hypertrophic cardiomyopathy.