Which abnormal heart sound may indicate heart failure?

The S3 gallop, often referred to as a third heart sound, is most closely associated with heart failure. This sound occurs when there is rapid filling of the ventricles during the early diastolic phase of the cardiac cycle. In the context of heart failure, the ventricles may be dilated or stiff, leading to a phenomenon known as volume overload. This rapid filling generates the distinct low-frequency sound of the S3 gallop, which can be detected using a stethoscope.

Patients with heart failure often present with an S3 gallop due to the increase in blood volume that places strain on the heart's ability to pump efficiently. The presence of this sound can be indicative of heart failure even in individuals without overt symptoms, making it an important sound for healthcare professionals to recognize during cardiac assessments.

This characteristic sound can assist in categorizing and assessing the severity of heart conditions, particularly in the early stages of heart failure where traditional symptoms may not yet be present.