EXPERIMENTAL ENDOCARDITIS DUE TO STREPTOCOCCUS VIRIDANS

Abstract

There are two distinct main aspects to the consideration of subacute bacterial endocarditis: (1) the mode of infection of the cardiac valves and (2) the factors involved in the continuance of the growth on the valve. The second aspect was the subject of the present investigation. We felt that it might prove to be of practical value to discover why infection due to a relatively nonvirulent organism persists on the cardiac valves. To this end the behavior of Streptococcus viridans was noted in various types of serum and whole blood, and the fate of the bacterium was investigated when placed in the blood stream, on a cardiac valve and in certain other tissues of the normal living dog. Horder,¹Schottmüller²and Libman and Celler³first observed the morphologic characteristics of Str. viridans and noted its relative nonvirulence. Since their observations innumerable studies have been made of the