DISEASES OF THE IIEAllT. — ENDOCARDITIS. 281 



These granulations are exceedingly frail. Not only does 

 their mutual contact during the closure of the valves splinter 

 and damage their soft tissues, but they speedily fall a prey to a 

 finely-granular, not fatty, metamorphosis of their entire sub- 

 stance ; this renders the vegetation so very brittle, that the 

 blood-current easily washes large and small bits of it away. 

 When this happens, a proportionate loss of substance, the 

 ^' endocarditic ulcer," is produced, which usually penetrates 

 clean throuo;h one lamella of the valve. The edo;es of the ulcer 

 are always irregularly raised ; they exhibit, so long as the endo- 

 carditis is on the increase, the primary stages of the process, 

 which extends to the neig-hbourino; connective tissue. A similar 

 extension occurs, though less frequently, at the base of the ulcer ; 



Fig. 87. 



Acute endocarditis. Section through one of the curtains of the 

 inflamed mitral valve, a. Upper, a', lower lamella of the 

 endocardium ; h. Intermediate layer, whose vessels are 

 congested; c. Efflorescence of upper lamella; d. Deposit 

 of fibrin; tV* 



the remaining lamella of the curtain becomes involved, and when 

 this yields the valve is perforated. Perforation of a valve is one 

 of the most dangerous accidents that can happen ; for the force 

 of the blood-current may easily dilate the original opening ; or 

 the curtain may bo detached on one or other side. In the 

 cuspid valves, it occasionally happens that the whole edge of the 

 curtain is detached together with the insertions of the nmsculi 

 papillares. The perforation, like the ulcer, is invariably fringed 

 with the inflammatory vegetations described above, which, in 

 consequence of the fibrinous deposit of which I am now about to 

 speak, may assume so great a size, that the opening in their 

 midst can hardly be detected. 



This rapid course of endocarditis in its most usual form never 

 issues in suppuration. This is anticipated hy the granular dis- 

 integration alluded to above — a sort of necrosis of the newly- 



