Final answer:
The S3 and S4 heart sounds are often referred to as 'ventricular gallop' and 'atrial gallop,' respectively. The sounds may be lifelong or may indicate certain heart conditions. They are colloquially named the 'Kentucky gallop' and 'Tennessee gallop' when S1, S2, and either S3 or S4 are heard together.
Step-by-step explanation:
The S3 and S4 heart sounds are additional sounds beyond the normal "lub-dub" that may be heard during cardiac auscultation. The third heart sound, or S3, is often associated with conditions such as congestive heart failure and is called a ventricular gallop.
It may also be heard in young, healthy individuals, as well as athletes and pregnant people. Some cardiologists refer to the combined S1, S2, and S3 sounds as the "Kentucky gallop" due to its resemblance to the cadence of a galloping horse. The fourth heart sound, S4, is referred to as an atrial gallop and is related to stiffness or hypertrophic conditions of the ventricle, suggesting possible left ventricular failure.
When S4 is combined with S1 and S2, this collective sound is termed the "Tennessee gallop". In some rare cases, when both S3 and S4 are present, the combined sound is referred to as S7.