Investigation of bacterial translocation in chronic ischemic heart failure in the rat.

Abstract

Increased markers of systemic inflammation had been found in patients with acute heart failure. These and other findings led to the hypothesis of an increased rate of bacterial translocation in severe or acute heart failure, leading to systemic inflammation. The present study examined if bacterial translocation occurs under physiological conditions in rats and if its rate and spectrum changes in chronic compensated ischemic heart failure. Myocardial infarction (MI) was induced by proximal ligation of the left anterior descending coronary artery or a sham operation was performed. Rats were followed up for six months and mesenteric lymph nodes of the surviving animals with large MI were excised and bacterial translocation was quantified by cultivating viable bacteria. Induction of a large MI led to a significant cardiac remodelling, elevated levels of atrial natriuretic peptide, and pulmonary oedema. There was no difference in the spectrum or in the rate of bacterial translocation compared with controls, neither comparing all cultured bacteria nor predefined subgroups (e.g., intestinal bacteria). Bacterial translocation is a physiological process with no gradual increase in chronic compensated heart failure in rats.