Heart valve dysplasia

Heart valve dysplasia is a congenital heart defect in which one or more of the four heart valves, the aortic, pulmonary, mitral and tricuspid valves, forms abnormally. Dysplasia of the mitral and tricuspid valves, the atrioventricular valves, can leave the valves thickened, shortened or notched, with fused or thickened chordae tendineae and enlarged or atrophied papillary muscles, and can cause blood to leak back or the valve to narrow. The article describes it chiefly in dogs and cats, where mitral stenosis is among the most common congenital heart defects in cats and certain breeds are more often affected. The cause is unknown, though genetics play a large role. Valve leakage leads to heart enlargement, arrhythmias and congestive heart failure; the condition may be tolerated for years or progress to heart failure within the first year of life, and diagnosis is by echocardiogram. This entry records what is held about the condition and is not medical advice.