Gallop rhythm

A gallop rhythm refers to a (usually abnormal) rhythm of the heart on auscultation.^[1] It includes three or four sounds,^[2] thus resembling the sounds of a gallop.

The normal heart rhythm contains two audible heart sounds called the first heart sound or (S₁) and the second heart sound (S₂) that give the well-known “lub-dub” rhythm. These two heart sounds are caused by the closing of valves in the heart.

A gallop rhythm contains another sound, called S₃ or S₄, dependent upon where in the cycle this added sound comes.

It can also contain both of these sounds forming a quadruple gallop, and in situations of very fast heart rate can produce a summation gallop where S₃ and S₄ occur so close as to be indistinguishable.

Gallop rhythms may be heard in young or athletic people, but may also be a sign of serious cardiac problems like heart failure.

• Kuo PT, Schnabel TG, Blakemore WS, Whereat AF (1957). “Diastolic gallop sounds, the mechanism of production”. J. Clin. Invest. 36 (7): 1035–42. doi:10.1172/JCI103499. PMC 1072690. PMID 13449156.CS1 maint: Multiple names: authors list (link)