How TAVI affects gut bacteria in people with severe aortic stenosis

Impact of Transcatheter Aortic Valve Implantation (TAVI) on the Gut Microbiota in Patients With Aortic Valve Stenosis

Observational Hippocration General Hospital · NCT07052071

This will test whether transcatheter aortic valve implantation (TAVI) changes the gut microbiota and related blood markers in people with severe aortic stenosis.

Quick facts

Study typeObservational
Enrollment40 (estimated)
SexAll
SponsorHippocration General Hospital Academic / other
Locations1 site (Athens)
Trial IDNCT07052071 on ClinicalTrials.gov

What this trial studies

This observational study will enroll 40 patients undergoing TAVI at Hippokration General Hospital in Athens and collect stool and blood samples before and several months after the procedure. Gut microbiota composition will be measured by 16S rRNA sequencing with the primary endpoint set at roughly two months post‑TAVI, and serum TMAO will be measured as a secondary marker. Clinical, echocardiographic and dietary questionnaire data will be collected to link haemodynamic changes and potential confounders to microbiome shifts. The design is longitudinal within-patient comparison rather than randomized or interventional.

Who should consider this trial

Good fit: Ideal candidates are adults with severe aortic stenosis who are scheduled for TAVI and who have not taken antibiotics, probiotics, systemic steroids, or similar medications in the month before enrollment.

Not a fit: Patients with recent antibiotic or probiotic use, inflammatory bowel disease, end‑stage liver or kidney disease, active infection, or ongoing cancer treatment are unlikely to benefit or be eligible for this study.

Why it matters

Potential benefit: If successful, the study could show that restoring valve function with TAVI favorably alters gut microbiota and metabolic markers, suggesting a reversible link between haemodynamics and intestinal ecology.

How similar studies have performed: Cardiac dysfunction has been associated with gut microbiome changes in prior research, but few studies have specifically examined microbiome shifts after TAVI, so this approach is relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Aortic stenosis suitable for TAVI

Exclusion Criteria:

Patients will be excluded if they present any condition or intervention that may independently affect gut microbiota composition. These include:

* Use of antibiotics, systemic corticosteroids, antivirals, probiotics, bile acid sequestrants, or new medications within one month prior to enrollment.
* History of inflammatory bowel disease.
* End-stage renal disease requiring dialysis.
* End-stage chronic liver disease.
* Acute infection. Patients with aortic stenosis due to rheumatic fever or infectious endocarditis will be excluded.
* Active cancer under treatment.
* Psychiatric illness impairing ability to consent.
* Substance or alcohol abuse.

Where this trial is running

Athens

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Aortic StenosisGut MicrobiomeGut MicrobiotaTAVI
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.