Lub-dub Sound (Linux)

The first sound, , is a lower-pitched, slightly longer sound that marks the beginning of systole (the heart's contraction phase).

Distinguishing "Lub" from "Dub" is the first step in diagnosing heart murmurs. lub-dub sound

| Sound | Medical Term | What causes it? | Timing | |-------|--------------|----------------|--------| | (S1) | First heart sound | Mitral & Tricuspid valves closing | Start of systole (ventricles contract to pump blood out) | | Dub (S2) | Second heart sound | Aortic & Pulmonic valves closing | End of systole / start of diastole (ventricles relax to fill) | The first sound, , is a lower-pitched, slightly

: These include the aortic valve and pulmonary valve , which control blood exiting the heart to the lungs and the rest of the body. S1: The "Lub" The "Lub" (S1) The "Lub-Dub" sound is the

The "lub-dub" sound you hear through a stethoscope is the rhythmic signature of your heart's valves closing to keep blood flowing in one direction. 1. The "Lub" (S1)

The "Lub-Dub" sound is the acoustic signature of a functioning heart. Contrary to popular belief, these sounds are caused by blood hitting the heart walls. Instead, they are caused by the sudden closure of the heart valves, which creates vibrations that travel through the chest wall.