Barnaby's Cavalier Attitudes

Helping He@rts be Healthy He@rts

Introduction

I have been a Cavalier King Charles Spaniel owner for many years now: both my first two Cavaliers were diagnosed with heart murmurs in their "middle age". At the time I knew nothing about MVD, and when my vet told us that Barnaby had a heart problem I was devastated; when the same thing happened two years later with Rufus, I just could not believe it!

How could it possibly happen that I was so unlucky as to have this happen to both my dogs - it must be surely be a chance in a million? Not so - I have since learned that this is a very common problem that affects many of these lovely little dogs...

What IS MVD (Mitral Valve Disease)?

Mitral valve disease is a degeneration of the mitral valve, which is one of the valves which control the flow of blood through the heart. The mitral valve is located between the left-hand filling chamber (atrium) and pumping chamber (ventricle), and consists of two leaflets which allow blood to flow from the lungs to the heart.

This valve may eventually lose its flexibility, and when this occurs, it starts to leak. Initially, mild mitral valve insufficiency causes no distress, but a heart murmur may be heard. Later, as the leak becomes more pronounced, the heart enlarges to compensate, and heart failure and other serious complications may occur. The severity of the murmur is graded from 1 (mild) to 6 (severe) and can be measured by auscultation (stethoscope) and Doppler echocardiograms (ultrasound scans).

In addition to the murmur, other symptoms may be coughing, build up of fluid in the lungs, etc., difficulty in breathing, exercise intolerance, and loss of appetite. Treatment in later stages of MVD may include the use of diuretics to remove excess fluid build-up in the lungs and body cavities, and vasodilators and beta blockers to help control blood circulation and heart rate.

Why is MVD a problem in Cavaliers?

Several breeds of dogs, mainly the smaller ones, are predisposed to suffer from MVD; but for most it does not result in heart failure and death, as it is usually a disease of old age and tends to progress slowly.

However, research has shown that MVD is about 21 times more likely to occur in Cavaliers than in the typical dog, and the onset of the disease typically occurs much earlier in life. Also once diagnosed, MVD will progress much more rapidly in Cavaliers. Statistics indicates that, by the age of five, around 50% of Cavaliers will be suffering from MVD, and a very large proportion of them will be sufferers by the age of ten.

What can we do to help eradicate MVD in our Cavaliers?

It is believed that MVD is "polygenetic", which means that more than one gene may be the cause, and that it has an hereditary basis. Thus the more that can be done to achieve late onset of MVD in our Cavaliers, the better chance we will have of eradicating the problem, and both purchasers and breeders can help work towards this goal.

Buying A Cavalier

As a purchaser, the most important guideline should be to only buy a puppy whose parents' hearts are clear. Ask the breeder for evidence of this. If possible, buy a puppy with parents and grandparents heart clear at age five or so. This will give you the best chance of not losing a Cavalier to MVD at a very young age.

Breeding

Raising the age of onset of MVD should be breeders’ immediate aim: it is strongly advised that breeding stock under five years of age should be limited to those Cavaliers with clear heart certificates. Breeders should select mature, certified heart-clear dogs rather than young ones for breeding, and have their breeding stock heart checked every year.

The Cavalier King Charles Spaniel Club (UK) have now issued guidelines to reduce the incidence of MVD in Cavaliers: and recommend that both the brood bitch and the stud dog should (preferably) be at least two and a half years old with a clear heart, and with parents with clear heart certificates, issued at five years of age or older.

Heart Testing

Heart testing facilities are available at many UK Club shows, and the Club publishes blank heart certificates which are available to both members and non-members. The forms may be completed either by general veterinary practitioners or by specialist cardiologists, but preferably a cardiologist should examine dogs whenever possible. Results from the forms submitted to the Club are entered on the Club database and the data is passed to The Animal Health Trust at Newmarket for research analysis. The information collected remains completely confidential.

Funding Research

Research is being done on MVD in various countries including the UK, USA, and Sweden. A major new collaborative study on MVD is being undertaken by the National University of Ireland, Galway and Edinburgh University's Veterinary School in Scotland. They are looking at the structure of cells in both healthy and diseased canine mitral valves to understand the mechanism whereby the valve becomes thickened and dysfunctional. I have requested that future funds raised through Helping Hearts go specifically to this new and important research project.

Both Helping Hearts and the Friends of the Cavalier King Charles Spaniel raise money that goes (via the UK Club Health Fund) towards funding such research in the UK.

The Friends of the Cavalier King Charles organize regular sponsored walks and other events. For more details visit Ros Loades’ web site.

Helping Hearts fund raising is done via sales of Cavalier screen savers, stationery and other items at UK Club shows and through our website; more recently by mail order sales through Patricia Allison’s new site Heartline UK; and through various online auctions of Cavalier items at eBay. Please continue to give us your support and help us to help our Cavaliers have healthy hearts.

Further Information

If you would like to learn more about MVD, please visit these web sites: