Which heart sound may disappear with diuresis?

The third heart sound (S3) is associated with rapid ventricular filling during early diastole, often indicative of increased volume overload, which can occur in conditions such as heart failure. When a patient is treated with diuretics, the excess fluid volume is reduced. This reduction in blood volume can alleviate the strain on the heart and lead to the diminishment or disappearance of S3.

S3 is often used as a clinical marker to assess heart failure, especially in a congested state. When diuretics effectively decrease fluid overload, the hemodynamic changes can minimize the turbulence that produces the S3 sound, leading to its disappearance. This can be perceived as an improvement in the patient's condition as the heart begins functioning more efficiently with less fluid load.

In contrast, the first heart sound (S1) and second heart sound (S2) are primarily related to the closure of heart valves and are less directly affected by changes in volume status. The fourth heart sound (S4) is associated with a stiff or hypertrophied ventricle and is usually present in conditions that lead to poor ventricular compliance, which diuretics do not typically resolve. Thus, the focus in this question leads directly to the S3 sound and its