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.

In healthy adults, there are two normal heart sounds, often described as a lub and a dub that occur in sequence with each heartbeat. These are the first heart sound (S 1) and second heart sound (S 2), produced by the closing of the atrioventricular valves and …

In a healthy adult, the heart makes two sounds, commonly described as ‘lub’ and ‘dub.’. The third and fourth sounds may be heard in some healthy people, but can indicate impairment of the heart function. S1 and S2 are high-pitched and S3 and S4 are low-pitched sounds.

2023年2月17日 · In a healthy adult, the heart makes a “lub-dub” sound. This happens as blood flows through the heart chambers and cardiac muscles contract and relax during each cardiac …

This shutting of the atrioventricular valves creates the first sound of your heartbeat -- "Lub!" By this time, the heart's electrical signal has passed from the atria into the ventricles, so while the atria relax, the ventricles contract.

2022年8月10日 · The cardiac cycle features four sounds. It is much easier to hear the first two noises, “lub” and “dub,” which are high pitched. The third and fourth sounds are low pitched and often quieter.

The lub dub sound is crucial for assessing heart function. It indicates proper closure of heart valves, which is essential for maintaining effective blood circulation.

Ever wonder why the heart sounds the way that it does? Opening and closing of heart valves makes the heart rhythm come alive with its lub dub beats...

If you put a stethoscope over the chest, you’ll usually hear something that sounds like lub dub, lub dub, lub dub, which repeats over and over again, with each cardiac cycle, or heartbeat.

The first “lub-dub” is the sound of the mitral and tricuspid valves closing. The second “lub-dub” is the sound of the aortic and pulmonary valves closing soon after. But if there is a problem, a murmur may be added to this normal “lub-dub.”