When a doctor listens to the heart of a person with a heart murmur, they may hear a whooshing, swishing, humming, or rasping sound. This is due to rapid, turbulent blood flow through the heart.

Heart murmurs are extra, unusual sounds heard during a heartbeat — but why do they happen? When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works.

S1 is the first heart sound that doctors can hear using a stethoscope. The vibrations that occur when the mitral and tricuspid valves in the heart close produce the S1 sound. There are two common ...