Which heart sound is most closely associated with heart failure?

• A. S3 heart sound
• B. S4 heart sound
• C. Murmur
• D. None of the above

Answer: (A)

S3 is most closely linked to heart failure because it reflects rapid, passive filling of a volume-overloaded ventricle during early diastole. In heart failure, especially with systolic dysfunction, the ventricle is dilated and filling pressures are elevated, so the sudden deceleration of blood as the ventricle accepts a large volume produces this extra, low-pitched sound just after S2. It’s typically heard best at the apex with the patient in the left lateral position using the bell. This sign signals increased filling pressures and congestive states, which is why it’s the hallmark finding associated with heart failure. By contrast, S4 indicates a stiff, hypertrophied ventricle from long-standing hypertension or other causes, a murmur points to valvular disease or abnormal flow rather than the classic heart failure picture, and none of the above would not be correct.