What condition is associated with the presence of an S4 heart sound?

The presence of an S4 heart sound, also known as an atrial gallop, is most commonly associated with restrictive cardiomyopathy. This heart sound arises from the vibrations of the ventricular wall associated with the rapid filling of the ventricles when the atria contract. In restrictive cardiomyopathy, the heart muscle becomes stiff and cannot fill properly, which can lead to increased pressures in the atria and resultant S4 sounds.

The S4 heart sound can indicate a heightened left atrial pressure, often due to a stiff ventricle, which is characteristic of restrictive cardiomyopathy. This condition typically results from various causes, including infiltrative diseases such as amyloidosis or fibrosis, leading to impaired diastolic filling.

While dilated cardiomyopathy, congestive heart failure, and coronary artery disease can be associated with other types of heart sounds, they are less specifically linked to S4. In dilated cardiomyopathy, the heart typically becomes enlarged and may produce an S3 heart sound more commonly due to volume overload. Congestive heart failure can result in both S3 and S4 sounds depending on the nature of left ventricular systolic and diastolic dysfunction, but S4 is particularly indicative of a stiff ventr