Amar J, Lelouvier B, Servant F, et al. - Since there exists an interplay between bacterial translocation and myocardial infarction (MI), researchers performed a quantitative (by 16S quantitative polymerase chain reaction) as well as qualitative (by 16S metagenomic sequencing) assessment of blood bacterial DNA in patients admitted for MI in this case control study, and determined the impact of blood LDL cholesterol level on this link. They compared 103 patients at high cardiovascular risk but free of coronary disease vs 99 patients who had an MI. Admissions for MI demonstrated significant rise in blood bacterial 16S ribosomal DNA concentration, which was independent of post-MI left ventricular function and was more pronounced in patients with low-density lipoprotein cholesterol ≥ 1 g/L. The onset of MI was accompanied by a significant alteration of the differences in the proportion of numerous bacterial taxa in blood, therefore, a blood microbiota signature of MI was defined. At least 6 of the bacterial taxa whose proportions were reduced in patients with MI were recognized to incorporate species capable of metabolizing cholesterol. A negative correlation was identified between LDL cholesterol level and the prognosis at the acute onset of MI and mortality; the mechanism underlying this correlation should be better understood using these findings.