356 DISEASES OF THE HEART. 



broken down into a finely-granular detritus, with a few fat-globules, 

 We can rarely get opportunity to observe myocarditis in this stage. 

 Much more commonly we find its results, in the form of irregular, rami- 

 fying collections, varying in size, of a reddish-white or white color, and 

 of a scar-like density, scattered through the muscular substance of the 

 heart. Sometimes this indurated tissue is spread over a large portion 

 of the heart-wall, and forms its sole component. Here the degener- 

 ated wall may yield to the pressure of the blood ; a protrusion may 

 form, and a true aneurism of the heart result, which is to be distin- 

 guished as chronic cardiac aneurism from that form described as acute 

 cardiac aneurism, in treating of endocarditis. Such sacs may attain 

 the size of a hazel-nut or even that of a hen's egg, or larger. The 

 scar-like walls usually grow thin from distention; they sometimes 

 ossify, and quite often their cavity contains masses of stratified fibrin, 

 such as we find in aneurism of arteries. The entire heart is generally 

 dilated as well as the aneurism, and, even when there is no aneurismal 

 pouch, numerous scars in the heart-wall will cause dilatation of the 

 organ. On the other hand, large scars in particular situations, as at 

 the approach to the aorta, may^ cause diminution of the capacity of the 

 heart (DittricKs true cardiac stricture). 



When endocarditis terminates in abscess, discoloration and soften- 

 ing prevails more and more in the muscle, until at last a collection of 

 yellow, purulent liquid, surrounded by softened and discolored muscu- 

 lar substance, is formed. Such an abscess rarely becomes incapsulated 

 and dries up ; perforation nearly always takes place, unless death occur 

 beforehand. If the perforation be into the pericardium, pericarditis 

 follows ; if into the cavity of the heart, the debris of its broken-down 

 tissue passes into the circulation, and numerous metastases are often 

 the consequence. The insertion of an aortic valve may be torn away 

 by the inward pointing of an abscess ; or communication between the 

 two sides of the heart may be set up ; even the entire cardiac wall 

 may suffer rupture. Tearing up of the muscular structure of the 

 heart by infiltration of the blood, which we have described in a pre- 

 vious chapter as acute cardiac aneurism, may, of course, occur with 

 equal or even greater ease in consequence of the pointing of such an 

 abscess to the interior. 



SYMPTOMS AND COUESE. Myocarditis is but seldom diagnosticated 

 with certainty during life. As a mild form of the disease complicates 

 almost every case of endocarditis, we seem warranted in the inference 

 that the substance of the heart is more seriously inflamed when the 

 region around it appears unduly sensitive (which it never is in pure en- 

 docarditis), still more so if there be great acceleration of the pulse, if 

 the pulse grow small, or, above all, if the heart's action become irreg 



