Are S3 And S4 Heart Sounds Normal

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As a medical professional, I often come across various heart sounds while examining patients. Two of the most common heart sounds are S3 and S4. These sounds, also known as gallops, can provide valuable insights into the functioning of the heart. In this article, I will discuss S3 and S4 heart sounds in detail and explore whether they are considered normal or abnormal.

S3 Heart Sound:

The S3 heart sound, often referred to as the “ventricular gallop,” is an additional sound that can be heard during diastole, the relaxation phase of the cardiac cycle. This sound occurs immediately after the S2 heart sound, which is the closing of the semilunar valves. The S3 sound is associated with rapid ventricular filling due to increased blood flow from the atria during early diastole.

Typically, the S3 sound is heard best at the apex of the heart with the bell of the stethoscope. It is often described as a low-frequency sound resembling the word “Kentucky.” Hearing an S3 heart sound can indicate various conditions, including heart failure, volume overload, or ventricular dysfunction. Therefore, it is generally considered an abnormal finding.

S4 Heart Sound:

The S4 heart sound, also known as the “atrial gallop,” occurs during late diastole, just before the S1 heart sound. It is caused by the contraction of the atria pushing blood into a stiff or hypertrophic ventricle. The S4 sound is best heard at the apex of the heart and is often described as a low-pitched sound similar to the word “Tennessee.”

Similar to the S3 sound, the presence of an S4 heart sound is usually an abnormal finding. It can be a sign of conditions such as myocardial infarction, ischemic heart disease, or hypertensive heart disease. The S4 sound is also commonly heard in patients with left ventricular hypertrophy or stiff ventricular walls.

Are S3 and S4 Heart Sounds Normal?

Although S3 and S4 heart sounds are typically considered abnormal findings, there are situations where they can be considered normal. In certain individuals, such as young athletes or pregnant women, mild S3 sounds may be present due to increased blood volume or physiological changes in the heart. These innocent S3 sounds are typically not associated with any underlying cardiac pathology and do not require extensive investigation or treatment.

However, it is crucial to remember that the diagnosis and interpretation of heart sounds are complex and should always be made by a trained medical professional. The presence of S3 or S4 heart sounds should prompt further evaluation, such as an echocardiogram, to assess the overall cardiac function and identify any underlying conditions or abnormalities.


In conclusion, S3 and S4 heart sounds are usually abnormal findings that can provide valuable information about the functioning of the heart. These sounds are often associated with various cardiac conditions and should be further evaluated by a healthcare professional. While there are instances where innocent or physiological S3 sounds can be considered normal, it is essential to approach these findings with care and thorough investigation.