When it dies off, all of a sudden now, the valve flap that it was holding on to can invert.

当其死亡时，瓣膜瓣突然翻转。

What you might be wondering is what stops the valve flaps from being pushed upward into the atria like an umbrella on a windy day.

您可能想知道的是，在大风天，是什么阻止了瓣膜像雨伞一样被向上推入心房。