Heart disease in chameleons

The heart is a muscle which collects blood full of oxygen from the lungs and pumps it around the body. It also collects blood full of carbon dioxide from the body and pumps it back to the lungs. This cycle goes on continuously.

In mammals the heart sits in the chest cavity and is divided into four chambers. The right atrium collects blood full of carbon dioxide from the body, sends it down to the right ventricle which then pumps it to the lungs. The left atrium collects blood full of oxygen from the lungs, sends it down to the left ventricle which pumps it around the body. Blood is constantly being pumped from right to left, via the lungs and travels around the body inside a series of tubes of varying diameters; these are known as blood vessels.

The heart of a chameleon differs from that of a mammal in several ways. It is specially adapted to suit the life of a reptile. In chameleons, the heart sits forward in the chest, between the front legs. Inside the heart of the chameleon there are three chambers; these are the right atrium, left atrium and the ventricle which acts as two separate ventricles. There is also an extra chamber outside the heart called the sinus venosus which collects blood.

Chameleons can move blood to wherever it is needed in the body. Remember how the mammal heart always pumps blood round the body from right to left? Chameleons can change the direction of the blood so that it can flow backwards; this is called the renal portal system and is one of the ways that chameleons can survive if they are short of oxygen or if they become dehydrated.

It is essential to ensure your chameleon’s housing is maintained at the correct temperature; if your chameleon is not maintained at the optimal body temperature, its heart cannot beat fast enough to keep the blood pumping to all the vital organs.

It is also vital to provide a good source of UV light and a balanced diet; the heart is a muscle and needs a constant supply of calcium to enable it to beat properly.

Heart disease is not commonly diagnosed in chameleons. Although maintaining good nutrition, temperature and housing can all help further in minimizing the risk of any problems developing.