The leading cause of death in Cavaliers is Heart Mitral Disease (MVD). It is estimated that over 50% of Cavaliers will have MVD by the age of 5 and 90% by the age of 10.
Numerous research studies on the Cavalier have found two distinct types of MVD. Early Onset, that is prior to the age of 5 and Late Onset, that is over the age of 5. In 1996 a group of Veterinary specialist (see end of page) designed a breeding protocol to reduce and eliminate early onset MVD.
The MVD Protocol
1. Every breeding Cavalier King Charles Spaniel should be examined annually by a board certified veterinarian Cardiologist.
2. Do not breed any Cavalier who is diagnosed with a MVD murmur under the age of 5 years.
3. Do not breed any CKCS before age 2.5 years.
4. Do not breed any Cavalier under the age of 5 years, unless its parents' hearts were free of MVD murmurs by age 5 years.
The MVD Protocol was adopted worldwide. The American clubs made it 'recommended' or 'suggested'. In contrast the Swedish and Dutch Clubs modified it but made it mandatory. Today the Swedish and Dutch statistics show a dramatic drop in the number of early onset MVD diagnosis. As of 2015 the Dutch club saw a 72% reduction on early onset MVD with the mandatory protocol.
Breaking news Nov 2015 DENMARK & SWEDISH: With rigorous MANDATORY MVD breeding protocols from 2001 to today the risk of early onset MVD has decreased 71% That was from 997 Cavaliers studied. They will continue mandatory protocols through 2017. March of 2015 Flanders and Belgium require mandatory MVD protocols and MRI scans for all Cavaliers to be bred.
The Cavalier King Charles Spaniel Club USA, the original club in the US lists the protocol above in their guidelines.
Unfortunately, the National Club for AKC - American Cavalier King Charles Spaniel Club, recognized the full protocol from 1998 to 2010. Then a new slate of officers replace it with a watered down version. There was no research to back up this decision. Their current recommended practice is 2 years or older and Cavalier with early onset presentations of MVD before 4 years of age should not be bred and only slight mention of ancestry. It is difficult to find the information buried in the Implications for Breeders on their web Heart Page.
In contrast there are Cavalier breeders in the US and abroad that have strictly followed the guidelines with two, three or more generations of MVD clear dogs have seen a reduction in early onset MVD.
There are many breeders that have Cavaliers well into their teens that are MVD clear. They routinely breed to stud dogs that are 2.5 years old with parents 5 plus years old and MVD clear or preferably the stud dog himself 5 years old and parents of 7.5 plus year old and MVD clear.
Girls that are 2.5 that have parents that are over 5 and that are all MVD clear. Check the ages of the parents of the potential puppy for sale as well as the ages of the grandparents and that their heart certificates are current. Ask to see heart certificates or proof on OFA and you make sure the breeder is following the 'real' MVD breeding protocol.
Just recently a group of researches published the identification of two gene markers for early onset MVD. This is exciting news and if a DNA test could be configured. Until then, strict adherance to the breeding protocols is paramount.
What is MVD ?
The heart is divided into four chambers. The lower chambers are called the ventricles and the upper chambers are the atria or if discussing just one it is called the atrium. There are valves in-between the chambers that open and close, thus keeping the blood flowing in one direction. The Mitral Valve is located between the left atrium and the left ventricle.
Thus the Mitral Valve is considered one of the most important parts to keep the heart functioning correctly and preventing blood from flowing backwards. If the mitral valve does not close properly, blood can flow back into the atrium preventing continuous blood flow. The heart has to work harder to keep the blood flowing causing the walls of the heart to thicken and eventually leads to congestive heart failure.
All Cavaliers need to be annualy examined with a stethoscope (auscultation exam). Most veterinarians can hear imperfections, clicks, heart murmurs and arrhythmias. If this is a dog for breeding then they need to be seen by a Board Certified Veterinarian Cardiologist (ACVIM). They will be given a certificate that is good for one year. Most reputable breeders will post the results on the Orthopedic Foundation for Animals (OFFA) data heath website. This is one of four required tests for a Cavalier to receive a CHIC number.
If a veterinarian hears a suspicious sound, they will do an echocardiogram with an ultrasound machine. Echocardiograms will give a visual display of the heart, blood flow and activity. Blood flow can be seen as blue or red depending on the direction on the new Ultrasound machines and gives a clear visual picture if there is Mitral Valve irregularities.
There are few outward symptoms or signs with a Cavalier that has mild MVD issues. It is not until it has fully progressed that you will notice shortness of breath, reduced activity, coughing or additional naps. That is why annual exams are most important.
The progression of MVD can be slow or rapid. It is generally accepted that early onset seems to progress faster than the later onset. There is no cure of MVD however, there are some excellent cost effective medications that are available. Most Cavaliers live a normal life if MVD is bought early and the progression is slowed. Medications should be given as prescribed and a special diet may be suggested.
With the potential risk of MVD, it is highly recommended to keep all Cavaliers on the thin side and well exercised. Added supplements of Vitamin C, Vitamin E. CoQ10, Fish Oils with Omega 3 and Antioxidants such as Antiox-Ultra 5000 by Sogeval Laboratories are all excellent.
The MVD Breeding Protocol has been designed to eliminate early-onset mitral valve disease. Veterinary cardiologists throughout North America & Europe conducted studies of MVD in Cavaliers in the 1990s.
A group of four world renowned veterinary cardiologists, Doctors Andrew Beardow from England, James Buchanan from the United States, Virginia Luis Fuentes from Scotland, and Bruce Keene from the US, and an internationally respected geneticist, Professor Lennart Swenson from Sweden, each presented reports on the results of their professional studies about the disease in1998. Their conclusions:
• MVD is the leading cause of death in cavaliers;
• It is a hereditary, genetic disorder;
• There has been no statistical improvement in cavaliers' mitral valves in the eleven years since the first studies; and
• The disease can be decreased and the age of onset delayed by following guidelines of only breeding cavaliers who are over the age of 2.5 years, have hearts free from MVD murmurs, and have parents whose hearts were MVD murmur-free at age 5 years. No cavaliers should be bred which have murmurs before age 5 years.
