Heart Valve disease is the most prevalent heart disease in dogs, responsible for almost ¾ of all cardiovascular disease in dogs. Its main feature is the thickening of the heart valves, and usually involves the tricuspid or mitral valve. Degenerative valve disease tends to be related to age and breed, with older, small-breed dogs suffering from it the most. It is the male of the species that is more prone to develop it than the female. Though the cause is not known, the disease is believed to be genetic in Cavalier King Charles Spaniels, which tend to be very susceptible to the disease.
When the valve fails to close in the manner required, blood flow becomes turbulent and is forced back into the atrium, causing elevated blood pressure. Consequent infection of the mitral valve results in an elevation in blood pressure in the lung capillaries and eventually fluid build-up in the lungs. An increase in blood pressure in the body’s veins takes place, and fluid builds-up in the abdomen in cases where the tri-cuspid valve is affected. More harm to the heart can happen as a result of sustained ultra-rapid blood flow reverting into the atrium, and also to the efforts of the body to balance the reduced blood flow. With time, this balancing act turns harmful instead of beneficial.
Dogs rarely display any symptoms during the initial phases of the condition, though a heart murmur might be detected. Progression of the disease causes the dog to develop unwillingness to move or exercise, breathing problems, and a cough. Reduced blood flow or arrhythmia may also result in loss of consciousness. Unexpected death may also occur, though this is rare.
It is possible for a veterinarian to frequently make a diagnosis for this particular degenerative disease by performing a physical check and using suitable imaging measures, such as echocardiography and chest x-rays. Electrocardiography can be used to detect developing arrhythmias.
Once the symptoms begin to show or when fluid in the lungs is discovered via chest x-rays, treatment of small-breed dogs should begin.
The treatment for initial symptoms of congestive heart failure are ACE inhibitors to lessen unpleasant hormonal effects resulting from activation of particular hormones, and to decrease mitral regurgitation and fluid in the lungs. Diuretics are also used to regulate fluid in the lungs, while arrhythmias might be handled using medication that boosts heart function and lowers symptoms of congestive heart failure. With appropriate treatment, affected dogs can enjoy long lives.