He thinks his heart is going to stop because he can't possibly know how this has happened.

他认为他的心脏要停止跳动了，因为他不可能知道这是怎么发生的。

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Blood clots can kill if they move to the heart and lungs and stop needed oxygen from reaching those important organs.

VOA: special.2009.07.14

Then you could stop worrying and put your heart at rest.

VOA: special.2010.07.18

But today, at the annual Scientific Sessions of the American Heart Association and in the medical journal Lancet, researchers announced that Tricor failed to stop heart attacks and prevent deaths in a five-year study of almost 10, 000 diabetics.

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In 1996, Acorn founder Cliff Alferness got the idea that something as simple as putting a sleeve over the heart could stop the heart's deterioration.

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They also found mercury, which would have been used stop the heart from decomposing.

BBC: Richard the Lionheart's mummified heart analysed