Endotoxin attacks the cardiovascular system: black death at the tollgate.

Bacteria have attacked the cardiovascular system since time immemorial. The propensity for pathogenic bacteria to effect cardiovascular collapse and death has shaped human history. Black Death, caused by Yersinia pestis, killed tens of millions in China, the Middle East, and decimated onethird of the European population in the 14th century. More recently, fatalities from toxic Escherchia coli and the sinister threat of bio-weapons serve as poignant reminders of the dangers of severe bacterial infections. The propinquity of bacteria as part of the normal flora poses an ever-present threat. Bacteria colonize humans in symbiotic and commensal relationships that are neither beneficial nor detrimental. However, disruption of normal barriers (e.g., skin or gastrointestinal tract) permits bacteria to invade into the bloodstream (bacteremia) and release toxins (endotoxemia). Severe infections induce systemic inflammatory responses (sepsis) that predispose to multiorgan failure, hypotension (septic shock), and death.