Why the silence between the Dub and the next Lub? That pause is —the heart’s rest and recharge phase. During this silence, the ventricles are relaxing, filling passively with blood from the atria. No valves are snapping shut. It’s the quietest part of the cycle.
To understand how the lub-dub heart sounds are produced, let's review the heart's structure and function. The heart consists of four chambers: what produces the lub dub heart sounds
If the heart were merely a pump squeezing fluid, it would sound like a sponge being wrung out—a soft, squishing noise. Instead, the heart sounds like a drum. That is because the "lub-dub" is the sound of and reverberation caused by high-pressure valves slamming shut. Why the silence between the Dub and the next Lub