With severe mitral regurgitation not only is there significant increase in the left side of the heart, but it is frequently accompanied by varying degrees of congestive heart failure.

It is very important that the parents of the puppy you are looking at were checked by a Cardiologist because mitral regurgitation occurs with such velocity that it produces turbulence, which is detected as a systolic murmur which is heard between the first and second heart sounds.  Most vets are not trained to hear a systolic murmur, but the Cardiologist specialize in this area.

Almost all dogs have MVD in their later years of life, but with Cavaliers the onset of MVD is in the early years.  So many breeders are not taking their breeding dogs to the Cardiologist for proper testing before they breed and this condition has gotten worse over years therefore affecting some Cavaliers before their 2nd birthday.  A Reputable Breeder will have their breeding dogs Certified by a Cardiologist and this will accompany the puppy to their new home.  If the breeder you are speaking with does not have a certification on the puppy's parents, most likely they do not test for this.

There have been extensive studies throughout the states, Canada and United Kingdom and approximately 80% of Cavaliers have MVD before they are 8 years old.

Retinal Dysplasia is an abnormal development of some of the visual cells of the retina, eventually leading to blindness.  There is no cure for this.  It can be discovered by a Ophthalmologist at a few weeks of age.

Entropion is where the eyelid folds abnormally and the lashes turn in on the eye and irritate the eye.  The  lower lid is most often the problem.  This can be treated surgically and if left untreated the vision can be threatened and it can lead to corneal ulceration.  Entropion could be hereditary.

Canine Hip Dysplasia (CHD) is the malformation and degeneration of the coxofemoral joints.  It is similar to arthritis in people and is one of the most common ailments in dogs.

The femur, or thigh bone, consists of the head (femoral head) and the neck (the part of the femur that joins the long shaft of the bone to the head).  The acetabulum forms the socket part of the joint and it is in this socket that the femoral head rests.  Poor congruence between the femoral head and acetabulum creates abnormal forces across the joint, interferes with normal development and overloads the articular cartilage causing microfractures and degeneration joint disease.

Dogs are not born with CHD.  As puppies grow, laxity of the muscles and ligaments surrounding the joint and the poor fit between the bones produces excess movement of the acetabulum.  The separation between the bones is called subluxation, and at its severity it can become a total dislocation (the femoral head leaves the acetabulum).  The surfaces of the bones start out completely smooth, but with CHD there begin to be changes (remodeling).  Bone rubbing against bone causes an irritation which results in irregular bone growth and wear on the articular surfaces.  These irregular surfaces result in Osteoarthritis which can cause significant pain. As the bone of the acetabular rim is ground away, it becomes shallower and it is now more difficult to keep the femoral head properly seated.  

Some common symptoms of the disease are pain, difficulty moving, lameness, difficulty getting up, difficulty in sleeping if they have to lay on their particular hip.  The only way to know if your dog has CHD is to have them x-rayed by your vet.

Patellar Luxation is the slipping of the patella or knee cap.  The patella is a small bone that is held in place by ligaments that shield the front of the stifle joint and should be located in the center of the knee joint.   As the knee joint is moved, the patella slides in a grove in the femur.  A luxating patella is a knee cap that moves out of the groove in the femur.

What causes this to occur is the muscles of the thigh attach directly or indirectly to the top of the knee cap.  There is a ligament, called the patellar ligament, which runs from the bottom of the knee cap to a point on the shin bone (tibia) just below the knee joint.  The patella luxates because the point of attachment of the patellar ligament is not on the midline of the tibia.  As the thigh muscles contract, the force is pulled against the groove (called the trochlear groove) on the inner side of the femur.  With this abnormal movement, the inner side of the groove wears down and the patella dislocates or moves out of its groove.  This makes it difficult for the dog to put his weight on the leg.

The patellar may dislocate toward the inside, called medial, or outside, called lateral, of the leg.  Medial patellar luxation is present at birth and can affect either or both legs.  Laterally luxating patellas are often the result of  trauma and can affect any pet.  Diagnosis is made on physical examination and may be confirmed with radiographs.