Heart disease in dogs and cats is caused by abnormalities in the structure and function of the heart. The disease will develop over time, but the final result is a severe condition affecting the heart's function called heart failure. It can be found since birth (congenital heart disease) in the age of not more than 1 year and heart disease in dogs and cats that occurs later (acquired heart disease). The disease develops in the age range from 6 years and up, is the most common characteristic and is often found in older dogs. Heart disease is divided into...