# The influence of acute and chronic coronary syndrome on the gut microbiome and downstream microbiome-derived metabolites—Microbiome in acute myocardial infarction—MIAMI-Trial

## TL;DR

This study explores how acute and chronic coronary syndrome affect the gut microbiome and its metabolites, finding that acute coronary syndrome increases butanoic acid-producing bacteria and serum butanoic acid levels.

## Contribution

The study identifies specific gut microbiome changes and metabolite shifts in acute coronary syndrome patients compared to chronic cases.

## Key findings

- ACS patients showed increased levels of Butyricicoccus and Butyricoccaceae during follow-up.
- Serum butanoic acid levels increased in ACS patients, while TMAO levels remained unchanged.
- No significant changes in microbiome alpha diversity were observed in either group.

## Abstract

Cardiovascular diseases (CVD) are the leading cause of morbidity and mortality in the industrialized world. The gut microbiome influences CVD, through atherogenic metabolites like trimethylamine N-oxide (TMAO) or protective effects through short-chain fatty acids (SCFA) production. The specific alterations in the gut microbiome and downstream metabolites in acute coronary syndrome (ACS) and chronic coronary syndrome (CCS) remain unclear. We enrolled ACS patients within 24 h of clinical presentation with a follow-up of 28 days, using CCS patients as controls. Gut microbiome composition, downstream metabolites, and cardiovascular function were assessed at both baseline and follow-up. Microbiome-derived metabolites were analyzed and gut microbiome samples were characterized by 16S rRNA gene analysis. We enrolled 40 patients, with 20 patients each in the ACS and CCS group. Alpha diversity of the microbiome did not differ throughout the follow-up. After ACS gut microbiome composition changed during the follow-up period with increased levels of Butyricicoccus and Butyricoccaceae, a pattern not observed in the CCS cohort. Downstream analysis of microbiome-derived metabolites SCFA revealed increased serum levels of butanoic acid, while TMAO levels remained unchanged. This small prospective observational non-randomized study, suggests that ACS may trigger an enrichment of butanoic acid-producing bacteria in the gut microbiome, accompanied by an increase in serum butanoic acid levels over 28 days. No significant changes in TMAO were observed. These insights could help develop approaches to reduce the burden of CVD. As a small pilot study, these findings require validation in larger ACS cohorts. Trial registration NCT, NCT05456802, Registered 30 June 2022, https://clinicaltrials.gov/study/NCT05122689