If the Vet is concerned that your pet may have a heart problem it may be necessary to take an electrocardiograph. This is a non-invasive procedure. Wires are attached to each of the patient’s limbs and one over the chest. These are connected to the E.C.G. machine which reads the electrical impulses across the heart. The machine traces an image of these impulses onto paper. This gives an accurate impression of the rate and rhythm of the heart as well as giving an idea of the size of the heart chambers.