The fourth heart sound or S4 is an extra heart sound that occurs during late diastole, immediately before the normal two "lub-dub" heart sounds (S 1 and S 2).

Sep 3, 2025 · By interpreting heart sounds, clinicians can identify normal cardiac function, valve closures, and detect early signs of heart disease. Understanding S1, S2, S3, and S4 sounds, along …

Feb 1, 2024 · On auscultation, it sounds like "Tenn-e-ssee," corresponding to S4, S1, and S2, also referred to as a "gallop." S4 is caused by increased ventricular filling during atrial contraction, …

This sound is normal in children, but when heard in adults it is often associated with ventricular dilation as occurs in systolic ventricular failure. The fourth heart sound (S4), when audible, is caused by the …

Oct 11, 2022 · What is the S4 heart sound and what does it indicate? Why listen for S4 sounds? An S4 heart sound is a low-pitched sound that occurs toward the end of the diastole. In some cases, an …

Nov 9, 2021 · Learn about S4, the fourth heart sound, listen to examples, take short lessons and compare to other heart sounds. For all medical professionals.

The fourth heart sound (S4) is defined as a sound produced by atrial contraction in late diastole, best heard with the bell of a stethoscope, and is associated with decreased ventricular compliance, often …

Dec 13, 2025 · Learn when S4 heart sounds are normal. This guide explains causes, diagnosis, and when to seek medical attention for this extra heart sound.

The other important filling sound that may be heard at the apex is the fourth heart sound. It occurs in late diastole, when atrial contraction causes rapid blood flow into the ventricle.

Aug 4, 2025 · This sound is produced by the forceful contraction of the atria pushing blood into a stiff or non-compliant ventricle. Unlike S3, an S4 heart sound is rarely considered physiological, especially …