When your vet examines your dog he will use a stethoscope to listen to your dog's heart. If heart disease is present, your vet may hear a change in the heart sounds. The heartbeat may be fast (or occasionally slow), irregular or there may be an unusual noise (a murmur).

X-rays and ultrasound scans may also be used. X-rays may show that the heart is enlarged and ultrasound can be used to see whether the heart muscle and valves are working normally. An electrocardiogram (ECG), records the electrical activity that causes the heart muscle to beat and can be used to see if the beat is irregular.

Ask your vet to check a new puppy as soon as you get it and they will listen to its heart to detect any possible congenital heart problems. You may want to return the puppy to the breeder (if you are not already too attached to it) or, if possible, consider early correction of defects before signs of disease develop.