What are murmurs in heart sounds?

• A. Turbulent blood flow
• B. Closure of AV valves
• C. Opening snap
• D. An abnormal heart sound

Answer: (A)

Murmurs are sounds produced by turbulent blood flow within the heart or great vessels. When blood moves through a valve that’s narrowed (stenosis) or leaky (regurgitation), or when there’s unusually high flow, the smooth stream becomes chaotic and creates vibrations you can hear with a stethoscope. That turbulent flow is the defining feature of a murmur, which is why this option is the best description.

Closure of the atrioventricular valves creates the first heart sound, not a murmur. An opening snap is a specific extra sound associated with certain valve pathologies like mitral stenosis. Saying “an abnormal heart sound” is true in a broad sense but doesn’t capture the particular mechanism behind murmurs—that they arise from turbulent flow.