The outer layer of this pouch is the fibrous pericardium and it helps keep the heart in place within the chest cavity.

心包的外层是纤维心包，其作用是把心脏固定在胸腔之内。

In chronic pericarditis, immune cells start to recruit fibroblasts which create lots of fibrin - a protein that makes the serous pericardium stiffer - a bit more like the fibrous pericardium.

在慢性心包炎中，免疫细胞募集成纤维细胞分泌大量纤维蛋白，使浆膜心包硬化，与纤维心包性质相似。

The tough outer layer, or fibrous pericardium, is made of dense connective tissue and helps protect the heart while anchoring it to some of the surrounding structures, so it doesn't like bounce all over the place while beating.

坚韧的外层，或纤维心包，由致密的结缔组织组成，有助于保护心脏，同时将其锚定在周围的一些结构上，所以它不喜欢跳动时到处反弹。