What is lubb-dubb sound when listening to the heart?

Answer 1

It's the sound of the blood hitting the walls of the valves as they close. That is pretty much the most basic way to explain it.

The first heart sound a low pitched "lubb it is caused by vibration of the AV valves and surrounding fluid as the valves close at the begining of ventricular systole and the 2nd heart sound "dub" results from the closure of the aortic and pulmonary semilunar valves at the begining of ventricle diastole.

The lub-dub sound is caused by the opening and closing of valves in the heart.

The lub sound is caused by the shutting of the bicuspid/mitral valve and the tricuspid valve. This occurs when blood from the atrial chambers enter the ventricles.

The dub sound is caused by the shutting of the aortic valve and the pulmonary valve. This occurs when the blood from the ventricles are pumped out into the lungs and the rest of the body.

This cycle will then repeat itself hence the constant lub-dub lub-dub lub-dub etc

The answer to that question is actually quite simple. I don't know if what you are asking is why does it make a thumping sound?? But if that is the case then I can answer that question. The sound you hear is the heart producing blood and circulating it throughout the body.

Hope that helps....
The 'lub' is the S1 sound. It occurs due to normal closure of the mitral and tricuspid (atrioventricular) valves. With these valves closed, systole commences and blood is actively squeezed from the ventricles. The second sound is the 'dub' or S2 sound. It occurs as the aortic (to LV) and pulmonary (to RV) valves close to prevent backflow from the blood ejected from the ventricles and marks the beginning of diastole (or filling) of the heart.
The "lubb" sound is produced when the atrioventricular valves in the heart close. These valves are deep inside the heart and are between the upper (atrial) and lower (ventricular) chambers. The "dupp" sound is created when the semilunar valves (aortic and pulmonary) close.

These valves are at the top of the heart and lead to the arteries that carry blood to either the lungs or the body. The "lubb" is the first heart sound and softer. The "dupp" sound is shorter and louder than the "lubb" sound. This is because the cusps of the semilunar valves are more rigid than the atrioventricular valves (mitral and tricuspid).
The closing of the heart valves.
Blood pumping through.

Answer 2

The lubb sound is produced when the atrioventricular valves (AV) in the heart close. These valves are deep inside the heart and are between the upper (atrial) and lower (ventricular) chambers. The dubb sound is created when the sinoatrial valves(SA)close. These valves are at the top of the heart and lead to the arteries that carry blood to both the lungs or the body.

Answer 3

This lub - dub sound comes because of the periodic contraction and relaxation of auricles and ventricles. This cycle is also known as cardiac cycle, whose time period is 0.8 seconds for a normal human being.

Answer 4

its the sound of the diastolic and systolic movements. when the heart goes lubb, the heart is relaxing (diastolic movement) and dialating to let blood enter the heart chambers. The dubb sound is the sound of systolic movements, where the heart contracts and pushes blood out of the heart around the body.

Answer 5

The first heart sound heard is 'lub'. 'lub' sound is produced when the heart contracts during the closure of AV (atrioventricular) valves. On the other hand, 'dub' sound is produced as the heart relaxes during the closure of the SL (semilunar) valves.

Answer 6

The lub-dub sound made by the heart is caused by the closing of valves. The first sound, commonly heard as lub, is produced by the AV valves and the second sound, or dub, is caused by the semilunar valves.

Answer 7

The valve that allows blood in and out opens and closets between every heartbeat.

Answer 8

When the the valves between the atria and ventricles close, you get the first heart sound. When the aortic and pulmonary valves close, you get the second heart sound.