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.

Active, not recruiting

Under way, not looking for participants. Everyone needed has enrolled. The study is still running.

Official record

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Trial summary

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
Are there results?: Not yet: the study is under way

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.

Switzerland1 site

Inselspital, Department of Cardiology
Bern, 3010

Other trials in Switzerland

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.

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 groups in NCT07565077
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.

1 Mar 202428 Feb 2029

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.
More trials run by Insel Gruppe AG, University Hospital BernThe sponsor's other registered studies.
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)

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 33204525
Li 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 34352088
Candellier 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 36967106
Rajamannan 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 19023094
Chong 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 34811445
Chong-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 39797472
Chong-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

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See locations

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Target Value Study to Evaluate the Safety and Efficacy of the Taurus NXT® Transcatheter Aortic Valve System for the Treatment of Severe Calcific Aortic Stenosis
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Rare Disease Patient Registry & Natural History Study - Coordination of Rare Diseases at Sanford
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RecruitingPhase 2
Vericiguat for the Inhibition of Calcific Aortic Valve Stenosis Progression
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Active, not recruiting
DurAVR™ THV EU-EFS
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All Calcific Aortic Valve Disease trials

Study at a glance

From the registry record, last updated by the sponsor on 8 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: Impact of Transcatheter Aortic Valve Implantation on the Composition and Function of the Gut Microbiota
ClinicalTrials.gov ID: NCT07565077
Acronym / sponsor ID: Swiss-GUT-TAVI / 2023-02339
Conditions: Calcific Aortic Valve Disease, Inflammation, Dysbiosis, TAVI
Keywords: Gut microbiota, Metabolomics
Study type: Observational
Recruitment status: Active, not recruiting
Enrolment: 40 participants (actual)
Lead sponsor: Insel Gruppe AG, University Hospital BernUniversity, hospital or other
Collaborators: Tours university
Study start: 1 Mar 2024 (actual)
Primary completion: 28 Feb 2026 (actual)
Study completion: 28 Feb 2029 (estimated)
First posted: 4 May 2026 (actual)
Results: Not posted in the source record

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Study design

Observational model: Cohort
Time perspective: Prospective
Number of arms: 1

Arm	Type	Receives
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.

Who may qualify

Sex: All
Healthy volunteers: Not accepted
Age groups: 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.

Key inclusion criteria (5 listed)

• 18 years or older

Key exclusion criteria (6 listed)

- 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).

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Primary outcome

Change in gut microbiota-derived metabolite levels before and after TAVI
Time frame: Baseline (pre-TAVI) and 3 months post-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).

5 secondary outcomes

Change in gut microbiota diversity after TAVI
Time frame: Baseline and 3 months post-TAVI
Change in gut microbiota taxonomic composition after TAVI
Time frame: Baseline and 3 months post-TAVI
Sex-specific differences in gut microbiota changes following TAVI
Time frame: Baseline and 3 months post-TAVI
Association between gut microbiota changes and systemic biomarkers
Time frame: Baseline and 3 months post-TAVI
Prognostic value of gut microbiota and metabolite changes after TAVI
Time frame: From baseline to 3 months post-TAVI (and clinical follow-up, if applicable)

Results and safety

This study is still under way. Results are not available in the source record yet.

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 8 May 2026.
Background: PubMed 33204525Liao 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.
Background: PubMed 34352088Li 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.
Background: PubMed 36967106Candellier 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.
Background: PubMed 19023094Rajamannan 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.
Background: PubMed 34811445Chong 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.
Background: PubMed 39797472Chong-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.
Background: PubMed 41618437Chong-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.
Individual participant dataSharing planned: 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.

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Active, not recruitingObservational study
Intravascular Lithotripsy in High Risk Calcified Iliac Anatomy for Transfemoral TAVR
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Active, not recruiting
Target Value Study to Evaluate the Safety and Efficacy of the Taurus NXT® Transcatheter Aortic Valve System for the Treatment of Severe Calcific Aortic Stenosis
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Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

The record lists no contact. Use the official record to reach the sponsor.

1 site in 1 country: see every site and its status.

Questions about this trial

What is this clinical trial studying?

An observational study of Calcific Aortic Valve Disease and Inflammation, run by Insel Gruppe AG, University Hospital Bern at 1 site in Switzerland.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 5 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: under way, not looking for participants, as of the sponsor's last update on 8 May 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Switzerland. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Change in gut microbiota-derived metabolite levels before and after TAVI (time frame: Baseline (pre-TAVI) and 3 months post-TAVI). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT07565077, which also lists 7 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 8 May 2026.