that's called the cardiac conduction system.

就是所谓的心脏传导系统
It consists of several important points.

它包括了几个重要的点
The first is called the sinoatrial node or SA node

第一个点称为窦房结或SA结
and it's in the right atrium.

它位于右心房
The next point is the atrial ventricular node

第二个点是房室结
which sits on a fibrous substance called the septum

位于纤维间隔中
which separates the atria from the ventricles.

即将心室与心房分开的房室隔
The heart is kind of tilted to one side,

心脏是向一侧倾斜的
it's not straight up and down,

并不是垂直上下的
so the atria are up here and the ventricles are down here,

心房在上方心室在下方
there's a septum in between and that's where this AV node sits.

中间是房室隔那就是房室结的所在
It turns out that this septum is electrically insulating

房室结是绝缘的