Calcific Aortic Valve DiseaseSwiss-GUT-TAVINCT07565077
Impact of TAVI on the Gut Microbiota and Its Metabolites
An observational study of Calcific Aortic Valve Disease and Inflammation, run by Insel Gruppe AG, University Hospital Bern at 1 site in Switzerland.
Trial summary
Aortic stenosis is a common heart valve disease in older adults. It occurs when the aortic valve becomes narrowed, making it harder for blood to flow from the heart to the rest of the body. Without treatment, this condition can lead to serious complications and reduced survival. Read more about this study
- Who is it for?
- Any age
- Conditions the study is for
- Calcific Aortic Valve Disease, Inflammation, Dysbiosis
- How many people
- 40 participants
- Where
- 1 siteSwitzerland
- Study dates
- 1 Mar 2024to 28 Feb 2029
- Phase
- Observational
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages Any age
- All sexes
- No healthy volunteers
- Child, Adult, Older adult
Study population: Adult patients with severe aortic valve disease referred for transcatheter aortic valve implantation (TAVI) at a single tertiary care center. Patients are enrolled prospectively and undergo evaluation of gut microbiota composition and metabolomic profiles before and after TAVI.
Who may be able to join
- • 18 years or older
- Hospitalized for TAVI or investigations before TAVI for significant aortic valve disease
- Severe CAS is defined as: high flow gradient with normal CO (mean gradient ≥40mmHg, Vmax≥4m/s, valve area ≤ 1cm² or ≤0,6cm/m²) or low flow low gradient (mean gradient<40mmHg, Vmax <4m/s, valve area ≤ 1cm² or ≤0,6cm/m², stroke volume < 35ml/m², LVEF<40%) confirmed by low dose dobutamine echo or high calcium score (> 1200 in women and > 2000 in men), paradoxical low-gradient CAS: LVEF > 55%, Vmax< 4m/s, mean gradient < 40mmHg, area < 1cm²)
- Combined aortic stenosis and aortic regurgitation, considered as severe valvular heart disease with a need for TAVI.
- Written informed consent
Who cannot join
- - Treatment interfering with the composition of the intestinal microbiota: local or systemic corticosteroids within the last 3 months, antibiotics within the last 3 months, antiretrovirals, bile acid chelators (questran and colesevelam), HIV-targeted antiretroviral therapies, selective serotonin reuptake inhibitor-type antidepressants
- Clinical criteria: history of cholecystectomy, documented chronic liver disease in the patient, failure to fast on the day of the blood test, inflammatory bowel disease
- Valve in valve TAVI.
- LVEF < 20%
- Patients requiring emergency intervention (myocardial infarction, acute aortic or mitral regurgitation, cardiogenic shock).
- AS of rheumatic origin, infective endocarditis.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Impact of Transcatheter Aortic Valve Implantation on the Composition and Function of the Gut Microbiota
Aortic stenosis is a common heart valve disease in older adults. It occurs when the aortic valve becomes narrowed, making it harder for blood to flow from the heart to the rest of the body. Without treatment, this condition can lead to serious complications and reduced survival. A widely used treatment is transcatheter aortic valve implantation (TAVI), a minimally invasive procedure that replaces the diseased valve and improves blood flow.
Recent research suggests that heart diseases, including aortic stenosis, may affect the gut (intestinal) environment. The gut contains trillions of microorganisms (called the gut microbiota) that play an important role in digestion, immunity, and overall health. In patients with heart conditions, reduced blood flow may impair the intestinal barrier and alter the balance of these microorganisms. This imbalance may contribute to inflammation and other complications.
Read more
This study aims to better understand how aortic stenosis and its treatment with TAVI influence the gut microbiota and intestinal health. Researchers will measure specific substances produced by gut bacteria (called metabolites) in blood and stool samples. These include bile acids, trimethylamine N-oxide (TMAO), tryptophan-related compounds, and short-chain fatty acids.
Samples will be collected before and three months after the TAVI procedure. In addition, genetic analysis of stool samples will be performed to identify and compare the types of bacteria present before and after treatment.
The goal is to determine whether improving heart function with TAVI can restore a healthier gut environment. This may help identify new ways to improve outcomes and reduce complications in patients with aortic stenosis.
- Conditions
- Calcific Aortic Valve Disease, Inflammation, Dysbiosis, TAVI
- Keywords
- Gut microbiota, Metabolomics
- Medical subject headings
- Inflammation, Dysbiosis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Patients with aortic stenosis undergoing TAVI | Patients with severe aortic stenosis undergoing transcatheter aortic valve implantation (TAVI) as part of routine clinical care. Assessments of gut microbiota composition and metabolomic profiles are performed before the procedure and at 3-month follow-up. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in gut microbiota-derived metabolite levels before and after TAVI
Quantitative assessment of key gut microbiota-derived metabolites-including bile acids (cholic, chenodeoxycholic, deoxycholic, and lithocholic acid measured via LC-MS in µmol/L), trimethylamine N-oxide (TMAO measured via LC-MS in µmol/L), tryptophan metabolites (measured via LC-MS in µmol/L), and short-chain fatty acids (SCFAs measured via GC-MS in µmol/g) in blood and stool samples, measured before and after transcatheter aortic valve implantation (TAVI).
Measured: Baseline (pre-TAVI) and 3 months post-TAVI
Secondary outcomes (5)
Change in gut microbiota diversity after TAVI
Assessment of gut microbiota diversity using 16S rRNA sequencing, including alpha diversity (measured by Shannon and Simpson indices on a scale of 0-10) and beta diversity (measured by Bray-Curtis dissimilarity index score from 0-1), in stool samples collected before and after TAVI.
Measured: Baseline and 3 months post-TAVI
Change in gut microbiota taxonomic composition after TAVI
Analysis of the relative abundance (measured as a percentage of total sequences (%)) and distribution of bacterial families in stool microbiota using 16S rRNA sequencing before and after TAVI.
Measured: Baseline and 3 months post-TAVI
Sex-specific differences in gut microbiota changes following TAVI
Comparison of gut microbiota diversity (Shannon Index score) and composition (relative abundance percentage (%)) between male and female patients before and after TAVI.
Measured: Baseline and 3 months post-TAVI
Association between gut microbiota changes and systemic biomarkers
Evaluation of the statistical correlation (Pearson or Spearman coefficient r) between changes in gut microbiota composition (relative abundance %) and metabolite levels (µmol/L) with systemic markers of inflammation (including IL-6, IL-10, and TNF-α concentration in pg/mL measured via the Meso Scale Discovery [MSD] electrochemiluminescence platform), and cardiovascular function (NT-proBNP in pg/mL).
Measured: Baseline and 3 months post-TAVI
Prognostic value of gut microbiota and metabolite changes after TAVI
Assessment of the statistical correlation (Hazard Ratio or Correlation Coefficient r) between changes in gut microbiota composition (relative abundance %) and metabolite levels (µmol/L) with clinical outcomes, including incidence of heart failure, hemolysis, mortality, and prosthetic valve dysfunction.
Measured: From baseline to 3 months post-TAVI (and clinical follow-up, if applicable)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted4 May 2026
- Study start1 Mar 2024
- Primary completion28 Feb 2026
- Study completion28 Feb 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (7)Papers the sponsor has linked to this study.
- Other trials for Calcific Aortic Valve DiseaseStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 40 participants (actual)
Sponsor and investigators
- Lead sponsor
- Insel Gruppe AG, University Hospital Bern
- Sponsor type
- University, hospital or other
- Collaborators
- Tours university
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07565077
- Sponsor's protocol ID
- 2023-02339
- Other IDs
- 2023
- Acronym
- Swiss-GUT-TAVI
- Status last verified
- May 2026
- First submitted
- 27 Apr 2026
- Last updated
- 8 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided: The plan for sharing individual participant data is currently under evaluation. Data sharing will be considered in compliance with institutional guidelines, ethical approvals, and applicable data protection regulations.
Publications
Liao Y, Liu C, Xiong T, Zhao M, Zheng W, Feng Y, Li Y, Ou Y, Zhao Z, Peng Y, Wei J, Li Q, Meng W, Liu X, Chen M. Metabolic Modulation and Potential Biomarkers of the Prognosis Identification for Severe Aortic Stenosis after TAVR by a Metabolomics Study. Cardiol Res Pract. 2020 Oct 28;2020:3946913. doi: 10.1155/2020/3946913. eCollection 2020.
PubMed 33204525Li J, Zeng Q, Xiong Z, Xian G, Liu Z, Zhan Q, Lai W, Ao L, Meng X, Ren H, Xu D. Trimethylamine N-oxide induces osteogenic responses in human aortic valve interstitial cells in vitro and aggravates aortic valve lesions in mice. Cardiovasc Res. 2022 Jun 29;118(8):2018-2030. doi: 10.1093/cvr/cvab243.
PubMed 34352088Candellier A, Issa N, Grissi M, Brouette T, Avondo C, Gomila C, Blot G, Gubler B, Touati G, Bennis Y, Caus T, Brazier M, Choukroun G, Tribouilloy C, Kamel S, Boudot C, Henaut L; Stop-As Investigators. Indoxyl-sulfate activation of the AhR- NF-kappaB pathway promotes interleukin-6 secretion and the subsequent osteogenic differentiation of human valvular interstitial cells from the aortic valve. J Mol Cell Cardiol. 2023 Jun;179:18-29. doi: 10.1016/j.yjmcc.2023.03.011. Epub 2023 Mar 24.
PubMed 36967106Rajamannan NM. Calcific aortic stenosis: lessons learned from experimental and clinical studies. Arterioscler Thromb Vasc Biol. 2009 Feb;29(2):162-8. doi: 10.1161/ATVBAHA.107.156752. Epub 2008 Nov 20.
PubMed 19023094Chong Nguyen C, Duboc D, Rainteau D, Sokol H, Humbert L, Seksik P, Bellino A, Abdoul H, Bouazza N, Treluyer JM, Saadi M, Wahbi K, Soliman H, Coffin B, Bado A, Le Gall M, Varenne O, Duboc H. Circulating bile acids concentration is predictive of coronary artery disease in human. Sci Rep. 2021 Nov 22;11(1):22661. doi: 10.1038/s41598-021-02144-y.
PubMed 34811445Chong-Nguyen C, Yilmaz B, Coles B, Sokol H, MacPherson A, Siepe M, Reineke D, Mosbahi S, Tomii D, Nakase M, Atighetchi S, Ferro C, Wingert C, Grani C, Pilgrim T, Windecker S, Blasco H, Dupuy C, Emond P, Banz Y, Losmanova T, Doring Y, Siontis GCM. A scoping review evaluating the current state of gut microbiota and its metabolites in valvular heart disease physiopathology. Eur J Clin Invest. 2025 Jun;55(6):e14381. doi: 10.1111/eci.14381. Epub 2025 Jan 10.
PubMed 39797472Chong-Nguyen C, Fuentes Artiles R, Pilgrim T, Yilmaz B, Doring Y. The gut-heart axis in coronary artery disease: a scoping and narrative review of sex-based microbial and metabolic disparities. Biol Sex Differ. 2026 Jan 30;17(1):24. doi: 10.1186/s13293-026-00824-w.
PubMed 41618437