WithdrawnNCT04268160Updated Jun 30, 2021

GPx Activity in Subjects With Aortic Stenosis Undergoing TAVR

An observational study in Glutathione Peroxidase Activity, Aortic Stenosis and Transcatheter Aortic Valve Replacement, sponsored by University of Florida. Withdrawn at 1 site in United States. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2021-06-30.

Sponsored by University of Florida · Observational

Why this study was withdrawn

Funding issues and closed with the IRB

Study type: Observational
Model: Cohort
Time perspective: Prospective
Enrollment: 0
Ages: 18 Years and older
Sex: All

Study summary

The aim of this project is to investigate the association of glutathione peroxidase (GPx) and severe aortic stenosis (AS), as well as the impact of transcatheter aortic valve replacement (TAVR) on GPx activity post-procedure. The burden of oxidative stress will be determined by the measurement of GPx, superoxide dismutase (SOD) and lipoprotein A (Lp(a)). We hypothesize GPx activity is reduced in participants with severe AS vs control groups and GPx activity is to increase after TAVR is performed.

Conditions studied

Glutathione Peroxidase Activity
Aortic Stenosis
Transcatheter Aortic Valve Replacement

Browse trials for

Keywords

glutathione peroxidase, GPx, aortic stenosis, transcatheter aortic valve replacement, TAVR

In context

Aortic Valve Stenosis

985 studies on the registry are indexed under Aortic Valve Stenosis; 283 are open to participants now.

Browse Aortic Valve Stenosis studies →

Lead sponsor

University of Florida is the lead sponsor of 1,254 studies on the registry; 201 are open to participants now.

Of its 170 completed or terminated interventional studies of FDA-regulated products, 136 (80%) have results posted.

Counted across the registry records on this site, refreshed daily.

Who can participate

Ages eligible: 18 Years and older
Sexes eligible: All
Accepts healthy volunteers: Yes
Sampling method: Probability sample

Study population

Study participants with severe aortic stenosis undergoing TAVR. They will be matched with patients without aortic stenosis based on age, gender, race, and co-morbidities (including stroke, history of coronary artery disease, heart failure, diabetes, hypertension, and other valvular diseases).

Inclusion criteria

Age >18 years
Patients with severe AS including participants with low flow, low gradient severe AS and paradoxical severe AS
Patients meeting criteria for TAVR procedure

Exclusion criteria

Exclusion Criteria:

Previous aortic valve replacement (surgical or TAVR)
Participants undergoing chemotherapy
End stage liver disease/cirrhosis (liver produces GSH)

Study design

Observational model: Cohort
Time perspective: Prospective
Enrollment: 0 participants (actual)
Patient registry: No

Groups and cohorts

Patients with severe aortic stenosis undergoing TAVR
GPx activity levels will be measured on the day of TAVR procedure, the day of discharge, 1 month, and 6 months after the procedure
Diagnostic Test: Blood draw to measure GPx activity · Diagnostic Test: Blood draw to measure SOD activity · Diagnostic Test: Blood draw to measure Lp(a) levels
Patients without aortic stenosis
GPx activity levels will be measured on day of recruitment
Diagnostic Test: Blood draw to measure GPx activity · Diagnostic Test: Blood draw to measure SOD activity · Diagnostic Test: Blood draw to measure Lp(a) levels

Interventions

Diagnostic testBlood draw to measure GPx activity
Routine blood draw to measure levels of blood markers.
Diagnostic testBlood draw to measure SOD activity
Routine blood draw to measure levels of blood markers.
Diagnostic testBlood draw to measure Lp(a) levels
Routine blood draw to measure levels of blood markers.

What researchers measure

Primary outcomes

Level of GPx in blood samples
Glutathione peroxidase activity levels measured from whole blood in U/L units in participants with severe aortic stenosis after transcatheter valve replacement compared with the matched population
Time frame: Baseline up to 6 months

Study locations

1 site

University of Florida
Jacksonville, Florida 32209, United States

References and documents

Publications

Redfors, B. A. (2017). Biomarkers in Aortic Stenosis: A systematic Review. Structural Heart. The Journal of the Heart Team, 1-13.
Otto CM. Aortic stenosis and hyperlipidemia: establishing a cause-effect relationship. Am Heart J. 2004 May;147(5):761-3. doi: 10.1016/j.ahj.2003.12.014. No abstract available. PubMed 15131528 ↗
Memet C, Gerede DM, Ozenci M, Akbulut IM, Acibuca A, Kilickap M, Erol C. Evaluation of the Role of Oxidative Stress in Degenerative Aortic Stenosis. J Heart Valve Dis. 2015 Jul;24(4):445-50. PubMed 26897814 ↗
Nimse, S. B. (2015). Free radicals, natural antioxidants, and their reaction mechanism. Royal Society of Chemistry, 27986-28006.
Blankenberg S, Rupprecht HJ, Bickel C, Torzewski M, Hafner G, Tiret L, Smieja M, Cambien F, Meyer J, Lackner KJ; AtheroGene Investigators. Glutathione peroxidase 1 activity and cardiovascular events in patients with coronary artery disease. N Engl J Med. 2003 Oct 23;349(17):1605-13. doi: 10.1056/NEJMoa030535. PubMed 14573732 ↗
Bolzan AD, Bianchi MS, Bianchi NO. Superoxide dismutase, catalase and glutathione peroxidase activities in human blood: influence of sex, age and cigarette smoking. Clin Biochem. 1997 Aug;30(6):449-54. doi: 10.1016/s0009-9120(97)00047-7. PubMed 9316738 ↗
Zheng KH, Tsimikas S, Pawade T, Kroon J, Jenkins WSA, Doris MK, White AC, Timmers NKLM, Hjortnaes J, Rogers MA, Aikawa E, Arsenault BJ, Witztum JL, Newby DE, Koschinsky ML, Fayad ZA, Stroes ESG, Boekholdt SM, Dweck MR. Lipoprotein(a) and Oxidized Phospholipids Promote Valve Calcification in Patients With Aortic Stenosis. J Am Coll Cardiol. 2019 May 7;73(17):2150-2162. doi: 10.1016/j.jacc.2019.01.070. PubMed 31047003 ↗
Arsenault BJ, Boekholdt SM, Dube MP, Rheaume E, Wareham NJ, Khaw KT, Sandhu MS, Tardif JC. Lipoprotein(a) levels, genotype, and incident aortic valve stenosis: a prospective Mendelian randomization study and replication in a case-control cohort. Circ Cardiovasc Genet. 2014 Jun;7(3):304-10. doi: 10.1161/CIRCGENETICS.113.000400. Epub 2014 Apr 5. PubMed 24704946 ↗
Mahmaljy H, Tawney A, Young M. Transcatheter Aortic Valve Replacement. 2023 Jul 24. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from http://www.ncbi.nlm.nih.gov/books/NBK431075/ PubMed 28613729 ↗

Individual participant data

Plan to share: No

Updates

Tracking since Sep 25, 2026

No changes since tracking began. The registry record was last updated on Jun 30, 2021, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗

Registry details

Key details

Study ID: NCT04268160
Lead sponsor: University of Florida
Responsible party: Sponsor
First posted: Feb 13, 2020
Start date: Nov 2020 (estimated)
Primary completion: Jun 15, 2021
Completion: Jun 15, 2021
Last update: Jun 30, 2021

Study contacts

Chinelo Udemgba, MD

principal investigator · University of Florida

Oversight

Data monitoring committee: No
FDA-regulated drug: No
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is withdrawn, as verified in Jun 2021. You cannot join it, but the record below documents what was studied.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Other studies in this condition

Aortic Valve Stenosis→

Other studies from this sponsor

University of Florida

Start the discussion