What is degenerative mitral valve disease? Degenerative mitral valve disease, also known as DMVD, is a degeneration of the valves in the heart. It can be seen in dogs and other animals such as horses and humans. Dogs with DMVD may experience breathlessness, weakness, coughing spells and weight loss. In some cases it leads to congestive heart failure or sudden death.

DMVD is degeneration of the mitral valve, which separates the left atrium from the ventricle. As a result, blood flow through this valve becomes limited or even blocked completely leading to congestive heart failure in some cases. Congestive heart failure happens when not enough healthy blood goes into your organs and tissues due to faulty valves that cannot allow it to pass freely between chambers of your heart. DMVD usually develops slowly over time so many owners are unable to identify an exact age for their dogs’ symptoms but may notice them earlier on if they have other pre-existing conditions such as obesity or high blood pressure.

Breeds that have a predisposition for DMVD include

  • Cavalier King Charles Spaniel
  • Cocker Spaniel
  • Japanese Chin
  • Dachshund
  • Lhasa Apso
  • Miniature and Toy Poodle
  • Norfolk Terrier

Some dogs may develop degenerative mitral valve disease at a younger age of about two years old while others do not experience any symptoms until they are older than seven or eight.

DMVD has been diagnosed more in females rather than males probably due to their internal anatomy that predisposes them to different diseases but this is still uncertain because it could be related with the fact that female dogs live longer on average compared to males.

Symptoms of DMVD

Some of symptoms of DMVD are shortness of breath, coughing spells and weight loss.

An easy and reliable way to monitor for signs of heart failure (fluid in the lungs or chest) is to monitor the breathing rate at home during sleep. A healthy dog will have a breathing rate of less than 30 breaths per minute. If the breathing rate is greater than 30 breaths per minute, this may be an indication that heart failure is present and medical attention should be sought.


Treatment depends on how much damage has been done by degenerative mitral valve disease but generally includes medications like diuretics, ACE inhibitors and digoxin. A special diet may be recommended to help treat the symptoms of degenerative mitral valve disease.

Treatment period for degenerative mitral valve disease in dogs is usually lifelong.

In severe cases, surgery is needed to replace the degenerated valve with a mechanical or bioprosthetic one. This procedure has been shown to reduce symptoms and improve prognosis but it may also cause other complications such as infections of post-operative wound on chest wall which can be addressed using antibiotics after surgery. Moreover, in some instances doctors may decide that there’s no point in going through this process because degenerative mitral disease has advanced too far even for a heart transplantation which does not always work anyway due to shortage of donor hearts available.

There are many different ways to treat degenerative mitral valve disease and your veterinarian will help you decide what’s best for your dog. Treatment may include medications, a special diet, surgery or even heart transplantation depending on the severity of the case. Dogs with DMVD require lifelong treatment so be sure to stick with whatever plan your veterinarian puts together for your furry friend.

Preventative steps

Preventative steps for DMVD can include moderate exercise, maintaining a healthy weight and avoiding high blood pressure.

Stages of Degenerative Mitral Disease

Stage A: these dogs do not have evidence of heart disease, but are at risk from a genetic point of view; dogs that are predisposed to mitral valve disease are in stage A, for example any Cavalier King Charles Spaniel.

Stage B1: this refers to dogs that have heart disease (characterised by a typical mitral regurgitation murmur) but do not have an enlarged heart on radiography/echocardiography or clinical signs of the disease.

Stage B2: mitral valve disease patients should be considered at this stage when evidence of cardiac enlargement on echocardiography/radiography is present but still no clinical signs of the disease are apparent.

Stage C: this refers to the onset of heart failure and the development of clinical signs, such as rapid and/or laboured breathing, that characterises pulmonary oedema.

Research on DMVD is being conducted every day and new information is being discovered all the time. If you think your dog may have degenerative mitral valve disease, please consult with your veterinarian to get a proper diagnosis.

Degenerative Mitral Valve Disease in Dogs

What You Need to Know

– Degenerative mitral valve disease (DMVD) is a heart condition that affects dogs

– DMVD can cause shortness of breath, coughing spells, weight loss and other symptoms

– A breathing rate greater than 30 breaths per minute during sleep may be an indication of heart failure

– Treatment spectrum for DMVD generally includes medications, a special diet and surgery

– Dogs with DMVD require lifelong treatment so be sure to stick with whatever plan your veterinarian prescribes