I'm gonna start with the left atrium.

我将要从左心房开始。

It then propagates out through both atria, including bachmann's bundle in the left atrium, and contracts both atria.

然后它传导到两个心房，包括通过Bachmann氏束到达左心房，并且导致两个心房的收缩。

Now, sometimes, individuals might have an atrial septal defect, a small opening between the right and left atrium.

同时，某些人患有房间隔缺损的，即右心房与左心房之间有一个小的缺口。

Finally, Marfan syndrome is a risk factor for mitral valve prolapse, where the mitral valve pouches into the left atrium during systole.

最后，马方综合征也是二尖瓣脱垂的一个危险因素，即二尖瓣在收缩期时突向左心房。

After entering the left atrium, the blood goes through the second atrioventricular valve called the mitral valve into the left ventricle.

进入左心房后，血液穿过第二个房室瓣膜，称为二尖瓣，进入左心室。

The oxygen-rich blood moves into a venule and then, eventually, into a pulmonary vein that dumps the blood into the left atrium.

富含氧气的血液汇入小静脉，最终进入肺静脉；肺静脉将血液排入左心房。

It can go up into the left atrium.

它可以进入左心房。

Once again, blood starts to back up in the left atrium, pulmonary veins, and pulmonary capillaries, ultimately leading to pulmonary hypertension and pulmonary edema.

血液又一次在左心房、肺静脉、肺毛细血管淤积，最终导致肺高压和肺水肿。

These pulmonary veins deliver the oxygenated blood to the left atrium.

这些肺静脉将含氧血液输送到左心房。

In these individuals, it's possible for a blood clot to go from the right atrium to the left atrium, bypassing the lungs completely.

在这些人中，栓子可能从右心房直接进入左心房，而不需要通过肺循环了。

This is the valve that separates the left atrium and the left ventricle.

这是分隔左心房和左心室的瓣膜。

Pulmonary blood vessels shrink pumping more blood through the pulmonary veins into the left atrium.

肺血管收缩，将更多的血液通过肺静脉泵入左心房。

In left atrial enlargement, depolarization of the left atrium lasts longer than normal.

左房扩大时，左房去极化持续时间比正常长。

Then fresh oxygenated blood comes from the lungs to the left atrium, goes to the left ventricle and is pumped through the aorta to the body.

然后新鲜的有氧血从肺部到左心房，再到左心室，后随主动脉泵入全身。

This trip from the right ventricle of the heart, through the pulmonary artery to the lungs, and back to the left atrium of the heart is called the pulmonary circulation.

血液从心脏右心室，经过肺动脉到肺，再由肺静脉回到心脏左心房的行程，被称为肺循环。

P wave is the summation of 2 smaller waves resulting from depolarization of the right atrium followed by that of the left atrium.

P波是右心房去极化，然后左心房去极化产生的2个较小波的总和。

So the thing that just happened here, where a wave of blood was pumped from the right ventricle to the lungs and then followed the lowest pressure back to the left atrium?

所以刚才发生的事情，一波血液从右心室泵入肺部，然后跟随最低压力回到左心房应该叫什么呢？

On the left side, blood's now pumped from the left ventricle out to the pulmonary artery to the lungs, and then comes back to the left atrium and left ventricle and restarts.

对于左边来说，血液现在从左心室泵到了肺动脉进入肺，最后回到左心房，再进入左心室，然后重复这一循环。

In right atrial enlargement, depolarization of the right atrium lasts longer than normal and its waveform extends to the end of that of the left atrium.

右心房扩大时，右心房除极持续时间比正常长，波形延伸至左心房末端。

From the lungs, freshly oxygenated blood flows back into the left atrium and passively passes through the mitral or bicuspid valve to fill the left ventricle.

新鲜的含氧血液从肺部流回左心房，被动地通过二尖瓣（bicuspid valve）注入左心室。