Degenerative Mitral Valve In Dogs

Degenerative Mitral valve disease (DMVD) occurs due to the degeneration of the mitral valves. This is the most prevalent valvular condition in dogs and approximately 30% of dog's aged over 10 (that is 1 in 10 dogs) are affected with DMVD. A valvular degenerative disease has many other names, such as chronic valve disease, valvular regurgitation, valvular insufficiency, myxomatous degeneration, or endocarditis.

Dog’s heart is separated into 4 heart chambers (2 atria and 2 ventricles) divided by a wall and two valves. The two valves are mitral on the left and the tricuspid on the right. These valves are actual flaps acting as gatekeepers permitting blood through the valves to gush from the atria and then into the ventricles (between heartbeats).

The de-oxygenated blood to the lungs is pumped by the right side of the heart in which CO 2 waste is eliminated and it is re-oxygenated. The blood (re-oxygenated) then moves into the left portion of the heart, to the left atrium through the pulmonary veins and the left ventricle, which pump out to the rest of the body through the pulmonary artery and as other arteries such as the aorta take care of the rest.

When the heart beats (contracts), ventricular pressure increases and results in the closure of the tricuspid and mitral valves. Then the blood that is trapped in the ventricles is expelled from the heart to the rest of the body. During the ventricle pumping, the blood and the valve keep the blood moving through the heart in the right direction and prevents the backward flow of blood into the atrium.

DMVD is a progressive deterioration that generally affects the mitral valves in the heart. Eventually, the thickening and leakage of the valves cause heart enlargement resulting in the weakening of the heart muscle. The heart can no longer hold the unusual blood flow resulting in congestive cardiac failure.

When the valves are not functioning properly, this also results in abnormal backward flow of the blood through the valve (regurgitation) causing a heart murmur.

• Rapid and shallow breathing
• Restless or agitation while sleeping
• Slow/fast/erratic heart rate
• Exercise intolerance
• Coughing or gagging
• Lack of appetite
• Distended belly
• Collapse or fainting

• Diuretics (water pills): To reduce fluid buildup in the body by eliminating extra fluid and salt. spironolactone, furosemide etc.
• Heart valve surgery: To repair or replace the damaged or diseased heart valves.
• Congestive heart failure: An angiotensin-converting enzyme (ACE) inhibitor (benazepril, lisinopril, or enalapril), diuretics like spironolactone, furosemide, etc.
• Extra medications that might be used are sildenafil, valsartan, sacubitril, and torsemide.

• Talk to Your Veterinarians and understand your pet’s treatment options.
• Pain can be so subtle in dogs –access your dog’s pain and watch out for any abnormal behavior.
• Don’t forget even sick dogs need a few low-stress activities and a lot of rest.
• Work with your vet to find the optimal dietary plan for your dog.
• Home remedies such as herbs, diet, and exercise will depend on your dog's age and stage of the disease they are in.

There are no dependable methods to prevent heart disease in dogs, particularly since few of the common types are hereditary. But you can take steps to help your dog live a healthy life.

Healthy diet: Always feed your pup a healthy diet that includes Omega-3 Fatty Acids (fish oil) and Taurine (amino acid).

Adequate exercise: Exercise is good for cardiac health. However, when your pup has been diagnosed with heart disease, make sure to limit strenuous exercises.

Cavalier King Charles Spaniel, Miniature Poodle, Shih Tzu, Maltese, Chihuahua, Cocker Spaniel, Miniature Schnauzer, Dachshund, Whippet, Pomeranian, Senior Dogs

1. Causes:

• Cardiac causes of DMVD include:
  • Congenital heart defects (especially Bicuspid aortic valve disease)
  • Heart muscle disease (such as hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, dilated cardiomyopathy, etc)
  • Myocarditis (inflammation of the myocardium)
  • Severe valve leakage and enlargement of the cardiac chambers (chronic degenerative mitral valve disease)
  • Trauma to the heart muscle (such as a dog being hit by a car)
  • Age-related changes
• Non-cardiac causes include:
  • Inflammation of the pancreas
  • Severe anemia (low red blood cell count)
  • Gastric dilatation-volvulus (stomach twists around filled fills with large amounts of air)
  • Muscular dystrophy
  • Anesthetic agents, toxins, and medications

2. Types:

• Regurgitation (leaking)
  • Mitral valve regurgitation
• Valvular stenosis (narrowing)
  • Mitral valve stenosis: the mitral valve narrowing
• Valvular prolapse (slipping out of place)
  • Mitral valve prolapse

3. Mortality:

In general, Valuvular diseases are serious and lead to life-threatening complications without proper treatment. Valvular diseases are the reason for high cardiovascular mortality in dogs.

4. Diagnosis:

• A complete blood count (CBC), chemistry profile
• X-ray
• Cardiac biomarker blood test - NTproBNP
• ECG (electrocardiograph) / echocardiogram
• Abdominal ultrasound

5. Prognosis:

The overall prognosis of infectious/ acute/ idiopathic valvular disease prognosis is excellent, with most dogs experiencing a complete recovery after appropriate treatment.

Veterinary cardiologists say that dogs with severe DMVD are those having other heart defects that are likely to have developed in tandem with the defect itself.

Dogs with a severe defect will start to show symptoms within three years of age. Congestive heart failure may develop in DMVD dogs once the heart gets weaker.

DMVD is also a hereditary condition that is considered to be the result of multiple genetic factors.

• Rapid and shallow breathing
• Restless or agitation while sleeping
• Slow/fast/erratic heart rate

• Use no salts in food or cooking.
• Canned, frozen, and prepared pet foods are high in sodium.
• Fresh meats are usually low in sodium.

The mainstays of a good low-sodium diet may be chicken, fresh beef, pork, bland macaroni, and/or low-sodium.

Acceptable foods (no salt!)

• Rice (plain white or brown rice, not flavored)
• Lean, home-cooked meats (chicken, turkey, beef, fish)
• Pasta
• Honey
• Low-sodium cheese (Look for the Heart Healthy labeling)
• Homemade soup
• Maple syrup
• Eggs, cooked
• Fresh vegetables/fruit (green beans, carrots, banana, apple, orange)

The prognosis for Degenerative mitral valve disease in dogs depends on its severity and how early it was treated. The survival rate for dogs that undergo surgical repair for idiopathic mitral valve diseases is good.

Obviously, recurrence of valvular diseases is not possible after surgical procedures. Many dogs can live normal lives if they are without any other complications. Dogs with mild symptoms can be managed with medications.