Clinical trial NCT06898541: Coronary Sinus Reducer in Coronary Microvascular Disease
Official title: Impact of the Coronary Sinus Reducer on Coronary Flow Reserve and Symptoms in Patients With Coronary Microvascular Disease
Study type: INTERVENTIONAL
Overall status: NOT_YET_RECRUITING
Phase: NA
Conditions: Angina (Stable)
Coronary Microvascular Disease
Keywords: Angina
Coronary microvascular disease
Coronary sinus reducer
Lead sponsor: UMC Utrecht
Sponsor class: OTHER
Collaborators: name: Radboud University Medical Center
name: Amsterdam UMC
name: Amphia Hospital
First posted: 2025-03-27
Enrollment: 50
Sex: ALL
Minimum age (years): 40
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief 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.


Eligibility criteria: Inclusion Criteria:

1. Coronary microvascular dysfunction 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 hyperemia.
2. No hemodynamically significant epicardial stenoses based on both non-hyperemic pressure ratio (NHPR; iFR\&gt;0.89, or RFR\&gt;0.89, or dFR\&gt;0.89) and fractional flow reserve (FFR\&gt;0.80) assessments.
3. Angina - Canadian Cardiovascular Society Class II-IV on maximal medical therapy.
4. Negative acetylcholine provocation testing with respect to epicardial or microvascular vasospasm (as such, patients with equivocal acetylcholine provocation test results are not eligible for enrolment).
5. Patient understands the nature of the procedure and provides written informed consent prior to enrolment.
6. Patient is willing to comply with specified follow-up evaluation.

Exclusion Criteria:

1. Age ≤ 40 years.
2. Pregnancy.
3. Recent acute coronary syndrome (within 3 months).
4. Recent revascularization with PCI (within 6 months).
5. Severe arrhythmias, including chronic atrial fibrillation.
6. Severe left ventricular impairment (left ventricular ejection fraction \&lt;25%).
7. Permanent pacemaker or defibrillator leads in the right ventricle or atrium.
8. Indication for cardiac resynchronization therapy.
9. Severe valvular heart disease.
10. History of tricuspid valve replacement or repair.
11. Mean right atrial pressure ≥15 mm Hg.
12. Known allergy to stainless steel or nickel.
13. Anomalous or abnormal CS anatomy (e.g., tortuosity, aberrant branch, persistent left superior vena cava).
14. CS diameter at the site of planned implantation greater than 13mm or less than 9.5mm as measured on the venogram.
15. Currently enrolled in another investigational device or drug trial that has not completed the primary endpoint or that clinically interferes with the current study endpoints.
16. Life expectancy \<1 year.

Primary outcomes:
measure: Change in coronary flow reserve
timeFrame: 6 months
measure: Angina episodes
timeFrame: 6 months
Secondary outcomes:
Other outcomes:
Locations:
Study officials:
References: