Transcatheter aortic valve implantation reduces plasma concentrations of TMAO and indoxyl sulfate: A prospective, multicenter cohort study.

Background: Intestinal microbial metabolites, such as trimethylamine-N-oxide (TMAO) and indoxyl sulfate (IS), have been suggested as markers for the progression of aortic stenosis (AS). However, the impact of transcatheter aortic valve implantation (TAVI) on these intestinal bacterial metabolites has not been evaluated in a multicenter clinical study. The aim of this study was to determine the effect of TAVI on plasma levels of intestinal bacterial metabolites and to assess the predictive value of these metabolites for major adverse cardiovascular events (MACE) following TAVI. M: ETHODS: Consecutive patients with AS referred for TAVI were enrolled in this study. Blood samples were collected one day before TAVI and at hospital discharge. The concentrations of intestinal microbial metabolites were measured using ultra performance liquid chromatograph coupled with a mass spectrometer.

Results: Plasma levels of TMAO and IS decreased after TAVI, compared to baseline (p ≤ 0.004 for all). Among 128 patients included in the study, 21 patients (16.4%) developed MACE during the median follow-up time of 404 days. Baseline plasma IS level was higher in patients with MACE, compared to those without MACE (p = 0.001). Increased baseline IS level predicted MACE with 75.0% sensitivity and 74.3% specificity independent of other clinical variables (OR 14.264, 95% CI 3.442-59.117, p < 0.001) and decreased the chance of event-free survival (plog rank < 0.001).

Conclusions: Plasma concentrations of TMAO and IS decreased after TAVI, compared to baseline. Elevated plasma IS levels were associated with a 14-fold increase in the odds of post-TAVI MACE during a median follow-up period of 404 days.