ENDOCARDITIS. 



345 



heart is especially liable to this disease during foetal life. On the other 

 nand, in extra-uterine life, it is almost as exclusively the left heart in 

 which we find endocarditis. Inflammation hardly ever affects the 

 whole lining of the organ, but confines itself rather to patches of vary- 

 ing size. As we have already remarked, however, it is from the valves, 

 and especially from the parts of them already alluded to, that the in- 

 flammation is apt to proceed. 



It has been customary to mention reddening and injection of the 

 endocardium as the first sign of endocarditis. Mokitansky, however, 

 observes, that it is only possible in rare instances to obtain a view of 

 an endocarditis in this stage, and warns against confounding the red- 

 ness of injection with the infiltration of the endocardium which takes 

 place after death. Foerster points out that this reddening by injection,, 

 which we find surrounding points which have already undergone fur- 

 ther derangement of texture, may be distinguished from the reddening 

 of post-mortem imbibition, as the latter is darker and merely involves 

 the superficial coats, while the reddening from injection exists in the 

 deeper layers only, in which, by means of the microscope, we may see 

 the capillaries filled with blood to bursting. 



Very soon we find a puffiness and swelling of the endocardium, as 

 its external layer thickens and enlarges. Virchow describes this in- 

 crease in volume as " consisting of a homogeneous, translucent, toler- 

 ably clear ground-substance, in which so many cells are imbedded, that 

 it might seem, at first sight, as though it were an accumulation of 

 growing epithelium." 



Besides this diffuse swelling of the endocardium, reddish or grayish- 

 red delicate villi often develop as the disease advances, which give the 

 endocardium a fine, granulated aspect, and which, sometimes, rapidly 

 grow into tolerably thick, coarsely granular papillse and warts. These 

 are very hard and firm at their base, while their round, bulbous, free ex- 

 tremities appear soft and gelatinous. At the base we find perfectly- 

 formed connective tissue, while the apex is still filled up by elements 

 which have not as yet organized into connective tissue. These excres- 

 cences, known as valvular vegetations, are outgrowths from the endocar- 

 dium, from proliferation of its connective tissue. Upon the auriculo- 

 ventricular valves, these excrescences often form a border of varying 

 width, close to the free edge of the valve, and spread hence, particu- 

 larly upon the chordae tendineae. On the semilunar valves, they 

 generally proceed from the noduli Morganii. We must beware of 

 mistaking the fibrinous deposits, which are apt to form upon the rough 

 and uneven surfaces of the valves, and almost always cover them, 

 for the vegetations themselves. 



This swelling of the endocardium, which is afterward converted 



