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A healthy valve opens fully and closes completely. However, if a valve is damaged, the "lub-dub" changes.

The second sound, the (medically known as S2 ), is shorter, sharper, and higher-pitched.

.bpm-control display: flex; align-items: center; justify-content: space-between; margin-top: 1rem; gap: 1rem; background: #00000044; padding: 0.5rem 1rem; border-radius: 60px;

I'll assume you're asking for a related to a "lub dub valves" concept — likely a cardiac simulation, medical training tool, or interactive visualization of heart valves producing the "lub-dub" sound.