A gallop rhythm refers to a (usually abnormal) rhythm of the heart on
auscultation.
It includes three or four sounds, thus resembling the sounds of a
gallop.
The normal heart rhythm contains two audible
heart sounds called S
1 and S
2 that give the well-known "lub-dub" rhythm; they are caused by the closing of
valves in the heart. The
first heart sound (S1) is closure of the valve at the end of ventricular filling (the tricuspid and mitral valves); the
second heart sound (S2), is closure of the aortic and/or the pulmonary valves as the ventricles relax. Extra sounds, (
third and/or
fourth heart sound, can be normal, especially in children, or with severe exercise, but are generally heard (on the left side) when ventricular function is impaired, e.g., in case of acute infarction or severe cardiac failure. The sounds are thought to be caused by the atrium, facing back-pressure, forcing volume into an incompletely emptied ventricle. Then, given tachycardia, a "gallop" is produced. With right-sided back pressure after pulmonary embolism, and therefore an incompletely emptied right ventricle, a right-sided gallop can occur.
Associated conditions
Gallop rhythms may be heard in young or athletic people, but may also be a sign of serious cardiac problems like
heart failure
Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome, a group of signs and symptoms caused by an impairment of the heart's blood pumping function. Symptoms typically include shortness of breath, excessive fatigue, ...
as well as
pulmonary edema
Pulmonary edema, also known as pulmonary congestion, is excessive liquid accumulation in the tissue and air spaces (usually alveoli) of the lungs. It leads to impaired gas exchange and may cause hypoxemia and respiratory failure. It is du ...
.
Gallop rhythms may be associated with the following:
* Ventricular overload
*
Sinus tachycardia
Sinus tachycardia is an elevated sinus rhythm characterized by an increase in the rate of electrical impulses arising from the sinoatrial node. In adults, sinus tachycardia is defined as a heart rate greater than 100 beats per minute (bpm). Th ...
References
Further reading
* http://circ.ahajournals.org/content/20/6/1053.short - American Heart Assoc., Gallop Rhythm of the Heart
*
External links
{{Cardiovascular system symptoms and signs
Cardiology