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 S1 and S2 that give the well-known "lub-dub" rhythm; they 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 as well as pulmonary edema.
Gallop rhythms may be associated with the following:
- Ventricular overload
- Sinus tachycardia
The atrium has to contract strongly to push the blood through the stiffened ventricle.
- Tavel ME (November 1996). "The appearance of gallop rhythm after exercise stress testing". Clin Cardiol. 19 (11): 887–91. doi:10.1002/clc.4960191109. PMID 8914783.
- chfpatients.com - suitable for non-medical people, but requires some knowledge of medical terms
- familypractice.com - requires knowledge of medical terms
- http://circ.ahajournals.org/content/20/6/1053.short - American Heart Assoc., Gallop Rhythm of the Heart
- 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.