The nurse is auscultating heart sounds on a client and hears an extra sound late in diastole, just before the S1. How should the nurse document this finding?
A.
The third heart sound (S3)
B.
A friction rub
C.
The fourth heart sound (S4)
D.
A split second heart sound S2
The correct answer and Explanation is:
The correct answer is:
C. The fourth heart sound (S4)
Explanation:
The fourth heart sound (S4), also known as an atrial gallop, occurs late in diastole, just before the first heart sound (S1). It is produced by the vibration of the ventricular walls caused by the atrial contraction and is associated with increased resistance to ventricular filling. The sound is best heard with the stethoscope placed at the apex of the heart with the client in a left lateral position.
The S4 sound is indicative of certain pathophysiological conditions. It is commonly associated with conditions that cause decreased ventricular compliance or increased resistance to filling, such as hypertension, aortic stenosis, or hypertrophic cardiomyopathy. It can also be heard in individuals with a stiff or hypertrophied left ventricle.
Here’s a brief overview of the other choices and why they are not correct for this finding:
A. The third heart sound (S3) is heard early in diastole, just after S2. It is sometimes referred to as a “ventricular gallop” and is often associated with heart failure or high cardiac output states. It would not be heard late in diastole.
B. A friction rub is a distinct, high-pitched, grating sound caused by the rubbing of inflamed pericardial layers against each other. It is typically heard during the cardiac cycle and is not associated with the late diastolic timing of the S4 sound.
D. A split second heart sound (S2) refers to the separation of the aortic and pulmonary components of the S2 sound, usually occurring during inspiration. This split occurs during systole, not late in diastole, so it does not fit the description of the finding.
In summary, an extra sound late in diastole, just before S1, should be documented as the fourth heart sound (S4), reflecting specific pathophysiological changes in the heart.