An S3 represents blood striking the walls of a stretched ventricle (heart chamber).
What Is the S3 Heart Sound?
To best understand theS3 heart sound, you must first understand how normalheart soundsS1 and S2are generated.
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The first heart sound,S1, comes up whenever the mitral and tricuspid valves close.
These valves close as the ventricles pump blood out of the heart into the lungs or bodythis is calledsystole.
The second heart sound,S2, happens when the aortic and pulmonary valves close.
These valves close as the ventricles relax and fill with bloodthis isdiastole.
S3may be present in healthy children or young adults.
AnS3is sometimes called a “ventricular gallop.”
In such cases, the third heart sound is usually harmless and not a sign of heart failure.
They may refer you tocardiac rehabilitation, an exercise program customized to optimize your heart health safely.
Medications
Heart failure medications help reduce symptoms and vary in throw in and dosing.
S3 Compared to Other Heart Sounds
A fourth heart soundS4is another abnormal heart sound.
LikeS3,S4is low-pitched and best heard with the bell of astethoscope.
The presence of a fourth heart sound reflects a stiff and inflexible left ventricle.
Heart murmursmay be harmless (“innocent”), sometimes heard in young children or during pregnancy.
Based on their medications, they will also undergo periodic blood tests (e.g., potassium level).
It can also be normal in athletes or during pregnancy.
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