Which heart sound is associated with increased ventricular filling?

The S3 heart sound, also known as the third heart sound, is associated with increased ventricular filling. It occurs during the rapid filling phase of the ventricles in early diastole when blood flows from the atria into the ventricles. In a healthy individual, the S3 sound is normal in children and young adults due to the compliant nature of their ventricles, which easily accommodate the volume of incoming blood.

In adults, particularly in conditions such as heart failure or volume overload, the presence of an S3 heart sound may indicate that the ventricles are experiencing increased filling pressures and can be a sign of left ventricular dysfunction. This is due to the fact that the high volume of blood entering the ventricle causes the heart to stretch more than normal, leading to the generation of this sound.

Understanding the S3 sound is crucial in clinical practice, as its identification can help indicate certain pathological states like congestive heart failure or other conditions where ventricular overload is a concern. The other choices reflect different physiological or pathophysiological states but do not directly relate to the mechanism of increased ventricular filling in the same specific way that the S3 sound does.