ClinicalTrials.gg
Sign In
Enrolling by invitationNCT06898541REDUCE CMDUpdated Dec 4, 2025

Coronary Sinus Reducer in Coronary Microvascular Disease

An interventional study of Coronary sinus reducer and Sham CSR procedure in Angina (Stable) and Coronary Microvascular Disease, sponsored by UMC Utrecht. Enrolling by invitation at 2 sites in Netherlands. Open to participants aged 40 Years and older. Per ClinicalTrials.gov, last updated 2025-12-04.

Sponsored by UMC Utrecht · Not applicable, Interventional, and Treatment

Phase
Not applicable
Study type
Interventional
Enrollment
50
Allocation
Randomized
Ages
40 Years and older
Sex
All
01

Study summary

Coronary microvascular dysfunction (CMD) is a common cause of treatment- resistant angina that lacks evidence-based treatment options. The coronary sinus reducer (CSR) is an hourglass-shaped stainless steel mesh, designed to create a controlled narrowing of the coronary sinus (CS). By augmenting CS pressure, CSR implantation was shown to improve myocardial perfusion, potentially providing a novel treatment for patients with CMD. REDUCE CMD is a placebo-controlled study of CSR in 50 patients with CMD. The main study endpoints are the change in coronary flow reserve from baseline to 6 months in the CSR-arm versus the placebo arm, and the difference in number of daily episodes of angina recorded on the ORBITA-app at 6 month follow-up in the CSR-arm versus the placebo arm.

02

Conditions studied

  • Angina (Stable)
  • Coronary Microvascular Disease

Keywords

  • Angina
  • Coronary microvascular disease
  • Coronary sinus reducer
03

In context

Angina, Stable

343 studies on the registry are indexed under Angina, Stable; 56 are open to participants now.

This study's planned enrollment of 50 is below the median of 150 across 230 interventional studies indexed under Angina, Stable.

Browse Angina, Stable studies →

Lead sponsor

UMC Utrecht is the lead sponsor of 364 studies on the registry; 82 are open to participants now.

Browse UMC Utrecht studies →

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

04

Who can participate

Ages eligible
40 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  1. Coronary microvascular dysfunction in the left anterior descending coronary artery (LAD) as expressed by abnormal absolute coronary flow reserve (CFR\<2.5) confirmed during the index study procedure using the continuous thermodilution technique and saline-induced coronary hyperaemia.
  2. Angina - Canadian Cardiovascular Society Class II-IV on at least two anti-anginals or maximally tolerated medical therapy if less than two.
  3. Patient understands the nature of the procedure and provides written for the study prior to enrolment.

Exclusion criteria

Exclusion criteria

  1. Age \< 18 years.
  2. Absence of symptoms reported on the ORBITA-app during the 2-week screening period.
  3. Presence of hemodynamically significant epicardial stenoses based on both non- hyperaemic pressure ratio (NHPR; iFR≤0.89, or RFR≤0.89, or dFR/dPR≤0.89) or fractional flow reserve (FFR≤0.80) assessments.
  4. Prior positive acetylcholine provocation test with respect to epicardial vasospasm following the COVADIS criteria.
  5. Mean right atrial pressure ≥15 mmHg
  6. Severe pulmonary hypertension.
  7. Coronary sinus anatomy not suitable for CSR implantation.
  8. Pregnancy or planned pregnancy within the next 12 months.
  9. Recent acute coronary syndrome (within 3 months).
  10. Recent revascularization with PCI (within 6 months).
  11. Severe arrhythmias, including chronic atrial fibrillation with persistent rapid ventricular response (>100bpm despite medication).
  12. Indication for cardiac resynchronization therapy.
  13. Severe left ventricular impairment ( \<35%).
  14. class IV or decompensated heart failure or hospitalization due to heart failure within 90 days before the index procedure.
  15. Recent implantation of a permanent pacemaker or defibrillator lead in the right ventricle or atrium (within 90 days before the index procedure).
  16. Presence of a pacemaker lead in the coronary sinus.
  17. Severe valvular heart disease.
  18. History of tricuspid valve replacement or repair.
  19. to short term dual antiplatelet therapy or lifelong aspirin treatment.
  20. Currently enrolled in another device or drug trial that has not completed the primary endpoint or that clinically interferes with the current study endpoints.
  21. Known inability to tolerate contrast medium.
  22. \<1 year.
Terms in these criteria, in plain language(6)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

LVEF (left ventricular ejection fraction)

The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.

NYHA class (heart failure)

The New York Heart Association’s four classes of how much heart failure limits physical activity.

I
No limits: ordinary activity causes no undue tiredness or breathlessness.
II
Slight limits: comfortable at rest, ordinary activity causes symptoms.
III
Marked limits: comfortable at rest, less than ordinary activity causes symptoms.
IV
Symptoms even at rest; any activity makes them worse.

Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.

Contraindication

A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

Life expectancy

The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.

05

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment
50 participants (estimated)

Study arms

  • Sham comparator
    Sham

    Patients in this arm undergo a sham CSR procedure.

    Other: Sham CSR procedure

  • Experimental
    CSR arm

    Patients in this arm undergo coronary sinus reducer implantation.

    Device: Coronary sinus reducer

Interventions

  • DeviceCoronary sinus reducer

    Implantation of a Coronary Sinus Reducer device

    Also known as: reducer

  • OtherSham CSR procedure

    Patients will undergo a complete sham CSR implantation procedure without actual deployment of the CSR.

    Also known as: Sham

06

What researchers measure

Primary outcomes

  1. Change in coronary flow reserve

    Change in coronary flow reserve from baseline to 6 months in the CSR-arm versus the placebo arm (measured by the continuous flow thermodilution technique using saline-induced coronary hyperaemia).

    Time frame: 6 months

  2. Angina episodes

    Difference in number of daily episodes of angina recorded on the ORBITA-app at 6 month follow-up in the CSR-arm versus the placebo arm.

    Time frame: 6 months

07

Study locations

2 sites
08

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Dec 4, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT06898541
Lead sponsor
UMC Utrecht
Collaborators
Radboud University Medical Center, Maasstad Hospital, Rotterdam, VieCuri, Venlo, the Netherlands
Responsible party
Tim P. van de Hoef (Principal Investigator, UMC Utrecht) — Principal investigator
First posted
Mar 27, 2025
Start date
Nov 20, 2025
Primary completion
May 1, 2028 (estimated)
Completion
Nov 1, 2028 (estimated)
Last update
Dec 4, 2025

Oversight

Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

Interested in this study?

Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.

No contact was published for this record. The registry link below has the sponsor’s details.

Follow this study

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

Sign in to follow

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

Angina, Stable →

Other studies from this sponsor

UMC Utrecht →

Start the discussion