There are several theories, but by far the most popular one is the Muscle Pump Theory.

有几种理论，但目前最流行的是肌肉运动的理论。

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Whereas conventional motor-powered pumps tend to get clogged, the artificial muscle pump has larger internal orifices, Walters said.

鉴于传统的电机驱动的泵往往堵塞，人造肌肉泵具有较大的内孔，沃尔特斯说。

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Hypertrophic cardiomyopathy (HCM). This is a disease in which the heart muscle (myocardium) becomes abnormally thick, making it harder for the heart to pump blood.

肥厚性心肌病(HCM)：患了此病，病人心脏的肌肉(心肌)会变得异常肥厚而无法向心脏输血。

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While watching a jellyfish at Boston's New England Aquarium, he was struck by how the creature used a muscle to pump its way through water, a mechanism similar to a beating heart.

WSJ: Jellyfish Hints at Fix for Damaged Hearts

Further laboratory tests showed that this defect disrupts the calcium pump in heart muscle cells.

BBC: Gene link to inherited heart disease

As the weakening heart tries to pump harder, the muscle gets bigger, but becomes deformed.

FORBES: Heart Failing? Put A Sock On It