Myocardial depression in sepsis

Myocardial failure is uniformly fatal when associated with post-traumatic sepsis and multisystem failure. Controversy exists as to whether endotoxin has a direct effect on the myocardium. A nonanoxic isolated arterially perfused rabbit interventricular septum was used in this study to evaluate the effects of endotoxin, live E. coli, and endotoxin/septic shock plasma on myocardial function and ultrastructure. Purified E. coli endotoxin and live E. coli bacteria did not have a significant direct effect on rabbit cardiac muscle function or ultrastructure. Perfusion of the rabbit septum with plasma from rabbits exsanguinated following a 2-hour septic or endotoxin shock insult, however, caused significant (p less than 0.02) myocardial depression when compared with control septa perfused with normal rabbit plasma. Septa perfused with shock plasma demonstrated ultrastructural alterations of mitochondria that were not noted in control preparations.