Pedigree cats need to be bred with care, choosing only healthy individuals without extreme conformation (such as flat faces or odd-shaped ears), and health testing should be done to prevent inherited diseases. To find out more, listen to this podcast by clicking on the play button below.
The picture above shows a Maine Coon cat who has recently had kittens: she has a lovely conformation and has been health tested for inherited diseases as well as being scanned to rule out cardiomyopathy.
Please note that I am unable to answer veterinary questions in comments. If you have questions or concerns about your pet's health it is always better to contact your vet.