The mitral valve is one of the four valves in the heart. It’s job is to separate the left atrium (the blood collecting chamber) from the left ventricle (the pumping chamber).
If your pet has a mitral valve issue, it usually means that the valve has started to degenerate. If the valve fails to fully closes after each pumping action, blood will flow backwards from the ventricle back into the atrium. This backward blood flow increases over time and in the final stages, the valve collapses completely, resulting in congestive heart failure. Unfortunately, this condition is non-reversible.
This condition slowly progresses over years, and many times it is not detected until the end. Early in the disease process, a veterinarian may hear a soft murmur when the affected valve starts to leak, but usually there is no noticeable change in the dog’s activity level or behavior, so the murmur is not deemed dangerous.
However, if your veterinarian detects a murmur, it’s important to monitor your pet for other signs of this condition, including tiring quickly, increased breathing rate or effort for the level of activity, excessive panting, and cough. Bring these issues up to the veterinarian if detected, so he or she knows the murmur is not to be ignored.