According to the valvular theory, the vibrations affected by the mitral and tricuspid valves closure in early systole produce the first heart sound (S1). S1 usually includes many frequency components.

根据瓣膜原理，第一心音(S1)是在心脏收缩期由二尖瓣和三尖瓣关闭时引起的振动产生的，含有多个频率分量。

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According to the valvular theory, the vibrations affected by the mitral and tricuspid valves closure in early systole produce the first heart sound (S1). S1 usually includes many frequency components.

根据瓣膜原理，第一心音(S1)是在心脏收缩期由二尖瓣和三尖瓣关闭时引起的振动产生的，含有多个频率分量。

youdao