Dogs can suffer from many heart conditions, the most common of which is called mitral regurgitation. This occurs especially in small breed, older dogs, and is due to a valve in the left side of the heart that no longer forms a seal when the heart contracts. The resultant turbulent blood flow produces a murmur which can be heard when a stethescope is placed on the chest. The treatment for this condition depends on how advanced the secondary heart changes are, which can be assessed with an ultrasound. There are many other heart problems that occur in dogs which can be detected during an exam.