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 …

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 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.

第一心音聽起來像是“lub”或“啦”，通常由二尖瓣(M)和三尖瓣(T)處發出，發生在心縮期，是其開始的標誌。 音調低而時間長。 這是由於血液衝擊血管，及產生的渦流，還有房室瓣的突然關閉引起的。

第一心音 (S1)主要是由于二尖瓣和三尖瓣关闭时，瓣叶突然紧张产生振动而发出的声音，声似LUB（跟我一起念出来）。 S1标志着心室收缩 (收缩期)的开始。 第二心音 (S2)主要是由于主动脉瓣和肺动脉瓣关闭引起瓣膜振动所致，声似DUB。 S2标志心室舒张 (舒张期)的开始。 注意：虽然S1和S2都是由两种瓣膜振动产生的，但是瓣膜几乎是同时关闭，人耳很难听到其中的差别，所以我们一般听到的S1和S2都是两种瓣膜同时关闭合成的一个音。 下面这个音频就是正常心音的特 …

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 cycle.

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... Rishi ...

The lub dub sound is primarily created by the closing of heart valves during the cardiac cycle. The first sound, “lub,” occurs when the atrioventricular valves close at the beginning of ventricular contraction. The second sound, “dub,” happens when the semilunar valves close after blood is pumped out. How does blood flow relate to what ...

One of its most recognizable features is the distinctive sound it makes—often described as a “lub dub.” Understanding what makes the lub dub sound involves delving into the mechanics of how the heart functions, exploring its anatomy, and examining how these elements combine to produce this iconic auditory signal. Understanding Heart Anatomy

这些声音通常被描述为持续不断的“lub-dub，lub-dub”。 第一个“lub-dub”是二尖瓣和三尖瓣关闭的声音。 第二个“lub-dub”是主动脉瓣和肺动脉瓣随后关闭的声音。