Extra heart vibrations that are produced as a result of a disturbance in the blood flow -- enough, in fact, to produce audible noise -- are referred to as murmurs. Often, the murmurs are classified according to a variety of characteristics, including their timing. Systolic murmurs, for example, occur when the heart muscle contracts; diastolic murmurs occur when the heart muscle relaxes between beats; and continuous and to-and-fro murmurs occur throughout all or most of the cardiac cycle.
Heart murmurs can occur in both dogs and cats. If you would like to learn more about how they affect dogs, please visit this page in the PetMD health library.
The symptoms associated with murmurs depend on a variety of characteristics, including their grade, configuration, and location. If, however, the murmur is associated with structural heart disease, your cat may display signs of congestive heart failure such as coughing, weakness, or exercise intolerance.
Grading Scale for Murmurs
Murmurs are caused by the following:
More specifically, the following are some conditions and diseases that may bring on murmurs:
Continuous or To-and-Fro Murmurs
In order to determine exactly what is causing the symptoms, your veterinarian must differentiate between a wide range of abnormal heart sounds -- split sounds, ejection sounds, gallop rhythms, and clicks, for example. He or she also must differentiate between abnormal lung and heart sounds, and listen to see if timing of abnormal sound is correlated with respiration or heartbeat.
The location and radiation of the murmur, as well as the timing during cardiac cycle, is another way to determine the underlying cause. This can be accomplished by conducting a variety of tests, including chest X-rays, Doppler studies, and echocardiography. A complete blood count, meanwhile, is one of the preferred methods for confirming anemic murmurs.
The return of food into the oral cavity after it has been swallowed
A wall or partition that is designed to divide and separate
The act of making an opening narrower.
Any body entrance or exit
An inflammation of the lining of the heart
A condition in which growth and development are not up to normal standards
A procedure that is used to evaluate the health and structures of the heart
In veterinary terms, used to refer to the front of the body.