Microbiota-derived Trimethylamine N-oxide Predicts Cardiovascular Risk After STEMI

Trimethylamine N-oxide (TMAO), a metabolite derived from the gut microbiota, is proatherogenic and associated with cardiovascular events. However, the change in TMAO with secondary prevention therapies for ST-segment elevation acute myocardial infarction (STEMI) remains unclear. The purpose of this study was to investigate the sequential change in TMAO levels in response to the current secondary prevention therapies in patients with STEMI and the clinical impact of TMAO levels on cardiovascular events We included 112 STEMI patients and measured plasma TMAO levels at the onset of STEMI and 10 months later (chronic phase). After the chronic-phase assessment, patients were followed up for cardiovascular events. Plasma TMAO levels significantly increased from the acute phase to the chronic phase of STEMI (median: 5.63 to 6.76 μM, P = 0.048). During a median period of 5.4 years, 17 patients experienced events. The chronic-phase TMAO level independently predicted future cardiovascular events (adjusted hazard ratio for 0.1 increase in log chronic-phase TMAO level: 1.343, 95% confidence interval 1.122–1.636, P = 0.001), but the acute-phase TMAO level did not. This study demonstrated the clinical importance of the chronic-phase TMAO levels on future cardiovascular events in patients after STEMI.