What is lub-dub sound in heart?

Listen to the Lub-Dub This sound comes from the valves shutting on the blood inside the heart. The first sound (the lub) happens when the mitral and tricuspid valves close. The next sound (the dub) happens when the aortic and pulmonary valves close after the blood has been squeezed out of the heart.

How is lub-dub created?

The heart tone “lub,” or S1, is caused by the closure of the mitral and tricuspid atrioventricular (AV) valves at the beginning of ventricular systole. The heart tone “dub,” or S2 ( a combination of A2 and P2), is caused by the closure of the aortic valve and pulmonary valve at the end of ventricular systole.

What happens during LUBB DUPP?

Normal heart sounds are called S1 and S2. They are the “lubb-dupp” sounds that are thought of as the heartbeat. These sounds are produced when the heart valves close.

Which is longer lub or dub?

The first heart sound (lub) is caused by sudden closure of bicuspid and tricuspid valves and is longer than the second heart sound (dup) which is caused by closure of semilunar valves.

What causes the first heart sound?

The first heart sound (S1) represents closure of the atrioventricular (mitral and tricuspid) valves as the ventricular pressures exceed atrial pressures at the beginning of systole (point a). S1 is normally a single sound because mitral and tricuspid valve closure occurs almost simultaneously.

What caused the second heart sound?

The second heart sound (S2) represents closure of the semilunar (aortic and pulmonary) valves (point d). S2 is normally split because the aortic valve (A2) closes before the pulmonary valve (P2). The closing pressure (the diastolic arterial pressure) on the left is 80 mmHg as compared to only 10 mmHg on the right.

What makes the first LUBB and second DUPP heart sounds?

These heart sounds are commonly described as “lubb-dupp”. The “lubb” occurs as the atrioventricular valves are closing at the beginning of the contraction of the ventricles or systole. The dupp sound occurs as the semilunar valves are closing at the end of systole.

What is a 3rd heart sound?

The third heart sound (S3) is a low-frequency, brief vibration occurring in early diastole at the end of the rapid diastolic filling period of the right or left ventricle (Figure 24.1) Synonymous terms include: ventricular gallop, early diastolic gallop, ventricular filling sound, and protodiastolic gallop.

Is S1 a lub or dub?

Identify: S1 – The first heart sound (lub) can be heard the loudest at the mitral area. This sound represents the closure of the mitral and tricuspid valves and is a low pitched, dull sound at the beginning of ventricular systole. S2 – The second heart sound (dub).