Which heart sound is typically associated with heart failure?

The third heart sound, known as S3, is often associated with heart failure, particularly in situations involving volume overload or diminished ventricular compliance. In a healthy heart, S3 may appear in certain conditions, such as during high cardiac output states in young athletes or pregnant women. However, when S3 is present in older adults, it typically suggests heart failure and increased filling pressures in the ventricles.

The sound occurs during the rapid filling phase of the ventricle, right after passive filling from the atria when blood rushes into the ventricles. This increased turbulence due to volume overload in heart failure leads to the characteristic sound. The presence of an S3 can indicate that the heart is struggling to accommodate the volume of blood efficiently as it fills, highlighting a reduced ejection fraction or diastolic dysfunction.

Understanding the clinical significance of S3 helps healthcare providers assess and manage heart failure more effectively. This sound often prompts further evaluation and intervention to address the underlying heart failure mechanism, hence its strong association with the condition.