Effect of Fecal Microbiota Transplantation on Arterial Stiffness in Alcohol-Related Liver Cirrhosis: A Prospective Pilot Study

BACKGROUND: Alcohol-related liver disease is frequently associated with systemic vascular dysfunction and increased arterial stiffness. This may contribute to adverse clinical outcomes. Modulation of the gut microbiota through fecal microbiota transplantation (FMT) has emerged as a potential therapeutic strategy in liver cirrhosis, but its influence on vascular stiffness in humans remains insufficiently characterized. METHODS: This prospective study evaluated arterial stiffness in patients with alcohol-related liver cirrhosis undergoing FMT. A control group received standard care. Vascular stiffness was assessed non-invasively using an oscillometric arteriograph based on pulse wave analysis. Measurements were performed at baseline and at one and three months after FMT under standardized conditions. The main indices assessed included aortic pulse wave velocity, augmentation index, ejection duration and return time. Direct microbiome sequencing and metabolomic profiling were not performed. RESULTS: At baseline, the study and control groups had comparable vascular stiffness profiles. Only minor differences in selected hemodynamic parameters were observed. At one month after intervention, no statistically significant differences in arterial stiffness indices were observed between groups. Longitudinal analysis within the FMT group also showed no significant changes in direct markers of arterial stiffness across the three-month follow-up period. A non-significant tendency toward reduced ejection duration was noted. CONCLUSIONS: In patients with advanced alcohol-related liver cirrhosis, FMT did not produce measurable short-term improvements in arterial stiffness. These findings suggest that short-term vascular effects of microbiota modulation may be difficult to detect in patients with advanced alcohol-related liver cirrhosis. Larger studies including earlier-stage patients, longer follow-up and direct microbiome and metabolomic assessment are needed to clarify potential vascular effects of FMT.