Introduction
Heart murmurs can occur in puppies or young dogs during their rapid growth phases. Puppies in the one to four month range require a high cardiac output during their period of rapid growth. The type of heart murmur, the cause and severity of it, as well as its effects on your dog are all factors that determine whether or not a diagnostic evaluation and treatment are required.
Causes of Heart Murmurs in Dogs
Heart murmurs can occur when the blood flow through the heart (called cardiac output) becomes excessively turbulent. It is usually because of some kind of leakage within the heart as a result of a problem such as faulty heart valves or a hole in the walls separating the chambers of the heart due to a birth defect.
Heart murmurs can occur in puppies or young dogs during their rapid growth phases. Puppies in the one to four month range require a high cardiac output during their period of rapid growth. This increased output is often enough to produce the velocity necessary to create turbulence, which results in a heart murmur. This is quite normal and is termed an innocent or functional murmur. Most puppies lose these murmurs in adulthood.
Other factors can cause murmurs. For example, a high fever or an anaemia may affect the viscosity or consistency of the blood enough to cause turbulent blood flow and a heart murmur. In short, anything that can increase the turbulence of blood flow through the heart chambers can produce a murmur.
The type of heart murmur, the cause and severity of it, as well as its effects on your dog are all factors that determine whether or not a diagnostic evaluation and treatment are required. Your veterinarian may take an electrocardiogram (to check out function), chest radiographs (to check out lungs and size of the heart), blood tests (to check for anaemia, heartworm, blood problems, etc.), and other tests such as ultrasonography (to check out the physical integrity of the heart, heart valves, and flow patterns of the blood).
Many dogs with heart murmurs lead normal, healthy lives for many years with no problems before requiring treatment. Some may require special diets (e.g. low salt diets) while still others can be maintained on medication. With the help of your veterinarian, the prognosis for heart problems improves when diagnosis and treatment are initiated early on in the course of the disease.