Mitral Valve Disease

This term encompasses many heart diseases envolving degenerative thickening and progressive deformity of one or more heart valves - mitral valve disease, mitral valve degeneration, mitral valve insufficiency etc. Mitral valve disease is a serious heart condition caused by the abnormal function of the valve that separates the upper and lower chamber of the left side of the heart. This disease is usually associated with heart murmur that can be heard with a stethoscope. It commonly affects Miniature Schnauzers, Chihuahuas, Fox terriers, Cocker spaniels, Cairn terriers, miniature poodles, Bull terriers, Boston terriers, King Charles spaniels, Miniature pinschers, Dachshunds, Doberman Pinschers and Shetland sheepdogs. Males are 50 percent more likely than females to be affected.

The diseases may result from congenital defect of the valve, defects in the muscles and tendons that operate the valve, or inflammation of the heart. The disease usually occurs in older dogs, however it is seen in young dogs and may result in premature death. Symptoms may include exercise intolerance, weakness, syncope (passing out), coughing at night or at rest because of a build-up of fluid in the lungs, shortness of breath, and lethargy.

Mildly affected dogs can have a good quality of life for years. It all depends on when the diagnosis is made and when therapy is applied. There are many dogs with degenerative mitral disease that never progress to heart failure. While the prognosis for dogs with mitral valve disease at advanced stage is poor, some dogs may be managed with medications and low-sodium diet for a period that varies from case to case. There is no prevention for mitral valve disease. Early detection and appropriate treatment of the disease may improve the prognosis.