The deeper layers of the endocardiumduring acute inflammation may become infiltrated with young cells, with resultant softening and destruction of the intercellular substance.
When it is opened it is seen to have a much lighter colour than the other cavities, owing to the greater thickness of itsendocardium obscuring the red muscle beneath.
By extension of inflammation of the endocardium or pericardium the muscle of the heart may become involved.
In acute inflammation we find a thickening and a roughened appearance of the endocardium throughout the cavities of the heart.
The endocardium may be stained from the imbibition of blood.
The endocardium is often blotched to a greater or less extent by sanguineous imbibition.
