Think of afterload as a hose with a nozzle.

可以将后视为带有喷嘴的软管。

If the nozzle is opened wide, afterload will decrease because there will be less resistance to flow.

如果喷嘴打开，则后减少，因为流阻较小。

This arterial pressure that represents the amount of resistance the ventricle has to overcome to eject blood is called the afterload.

心室必须克服以排出血液的阻力的脉压力称为后。

When afterload is high, the heart has to work harder to pump blood.

当后很高时，心脏必须更加努力来泵血。

In other words, increased afterload results in increased end-systolic volume and less blood leaving the heart, or decreased stroke volume.

换言之，后增加导致收缩末期容积增加，离开心脏的血液减少，或每博输出量减少。

If the nozzle is almost closed, afterload will increase because there will be a lot of resistance to the flow of blood through the hose.

如果喷嘴几乎关闭，则后增加，因为对通过软管的血液流产生很大的阻力。

In this situation, the left ventricle is healthy but simply can't effectively pump blood in a system with such high afterload - in other words, under conditions with such high systemic pressures.

这种情况下，左心室完好，但由于后过重，不能有效泵血至全身；换言之，即在全身性高血压的情况下。

Therefore, we can see that when afterload is high, the heart would have a harder time pumping blood and would lead to an increase in the blood remaining in the ventricles, or an increased end-systolic volume.

因此，我们可以看到，当后很高时，心脏将很难泵血，导致心室中剩余血液增加或收缩末期容积增加。