Degenerative Valvular Disease



Endocardiosis also called valvular valvular insufficiency or valvular heart disease, degenerative mitral valve disease is the most common heart disease in the dog (80% of cases of chronic heart failure are secondary to this condition). It mainly affects small dogs
(Cavalier King Charles, Yorkshire, Poodle, etc.).

Causes

Degenerative valvular disease is caused by an alteration of the heart valves. These valves, two in number (mitral valve to the left heart, tricuspid valve to the right), ensure the flow of blood from the atria to the ventricles. Alteration causes a leak during contraction of the heart muscle, resulting in a partial reflux of blood into the atria with each beat. This results in an overload in the atrium and a lower volume of blood ejected by the heart into the arteries. Most of the time, alteration concerns the mitral valve (left). The tricuspid valve (right) may also be affected (Mixed reached more isolated tricuspid rarely achieved). Degenerative valvular disease has a hereditary component of polygenic * whose importance varies with the breed. Other factors, such as stress, hypertension, hypoxia, and endocrine disorders infectious disease may also help.





The evolution

The development is spread over several months or years. When the lesions progress valves, leakage of blood into the atria increases. To adapt to this overload, the atrium expands, then it is the turn of the ventricle. Then, several complications can be observed in different ways: abnormal heart rhythms (arrhythmias), cough and pulmonary edema in cases of infringement of the left heart, collection of fluid in the abdomen (ascites) or chest (pleural) breach of right heart failure, renal failure ... The broken rope clips (valves) is another possible complication of the disease, which worsens leakage and darkens the prognosis. Please note that dogs with this disease usually die of damage to other organs by the disease and "heart attack".

Clinical signs

Many dogs do not express any sign, because the disease develops late (6-8 years) and very gradually. It is found and often overlooked by other geriatric conditions more apparent. Among individuals with earlier and / or more important, as is the case in predisposed breeds, the first symptoms may appear as early as 3-4 years as coughing, fatigue, difficulty breathing, or even syncopation ... the diagnosis is made by a veterinarian using several tests:

- Auscultation of the heart: the presence of a heart murmur and possible arrhythmias. The breath is produced by the flow of blood into the atrium through the valve fully closed. Therefore, its intensity increases with the degree of damage.

- Radiography: assessment of cardiac dilatation, search vascular dilations, pulmonary edema

- Ultrasound: evaluation of cardiac activity and observation of intracardiac structures (walls, cavities, valves ...), followed by the evolution of the disease. Used to characterize different stages of heart failure and adapt the treatment.


The classifications used are as follows :

Stage 0 or Grade 0: The mitral leaflets are intact, No No nodule thickening They coaptent perfectly convex to the left ventricle throughout the cardiac contraction phase.

Stage 1 or Grade 1: We note a subtle thickening or the presence of a nodule and especially discrete flattening of both mitral leaflets (in reference to the plane of the mitral annulus). This flattening affects only the body slips and does not exceed the level of the mitral annulus.

Grade 2 or Grade 2: deformation and infiltration of both mitral leaflets are evident throughout the cardiac cycle. Sheets appear elongated, they are clearly flattened, reach and even exceed the anatomical level of the mitral annulus.

Grade 3 or Grade 3: The deformation and the mitral valve prolapse are more obvious, but especially at this stage is characterized by a very visible dilatation of the atrium (formerly headset) left. These anomalies cause defective closure and sealing of the valve, causing a leak itself generate the mitral breath. This breath is constantly detectable in stage 3, stage 2 inconsistently, depending on the quality of the stethoscope, the heart rate of the dog, the dog's weight status, breath sounds, and a host of outdoor events making method listening too random.

Stage 4 or Grade 4: Out of rope that affects the vast majority of the septal mitral leaflet. Dilatation of the left atrium.



Treatment

Unfortunately there is no cure for degenerative mitral valve disease. Several medications can nevertheless improve the comfort of the living animal, and slow the progression of the disease. The treatment will be more effective if it is started early. The veterinarian will adjust its processing depending on the stage of the disease and the signs observed. In general, the therapeutic strategy aims to facilitate the work of the heart and increase efficiency.

Why Test ?

Screening can detect disease before the onset of early signs and therefore, implement an early treatment of affected individuals. It also helps to guide the selection of breeding to reduce the frequency of this condition. Indeed, although it has long been controversial, the importance of genetics is now proven in Cavalier King Charles (and very likely in other small breeds). Club breed of Cavalier King Charles has implemented a policy to eradicate this disease, and asks farmers to submit their breeding accurate ultrasound examination (standard protocol). In addition, the rating scale * breeding requires that ultrasound examination of the heart older than 18 months has been achieved from the 3rd rating level. For subjects less than 2 years, ultrasound examination should be normal. Between 2 and 3 years, achieving Stage 1 is tolerated. Beyond 3 years, reached stage 2 is tolerated.



Source: Magali and Michèle Breton Colin, Veterinarians, Engineering Gipsa


When King Charles breeder sign the "quality charter" club race,

it undertakes, among other things, to conduct research possible heart defects and eye

in all breeding.


Our veterinarians plate


A beautiful stained glass


A smiling and knowledgeable


The cardiac examination is called "ultrasound - Doppler."

It highlights any abnormal operation
heart muscle.

Iconography of the review is sent to Dr. Haroutunian,
cardiologist club, which interprets the images.

Following this interpretation, the ability to reproduce
examined whether or not the dog is sent to the breeder.

The first echocardiogram is performed when the standard
running or reached 18 months. It shall be renewed periodically
throughout the dog's life.


Our Berlioz ready to shoot during the ultrasound




Gently and calmly


The ultrasound





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