Beta-blockers to improve coronary blood flow and resistance in people with angina and no blocked coronary arteries

Effect of Beta-blockers on Coronary Flow and Resistance in Patients With ANOCA: a Randomised, Placebo-controlled, Mechanistic Study

Phase 4 Interventional VZW Cardiovascular Research Center Aalst · NCT06864234

This trial will see if a beta-blocker (metoprolol) helps people with angina but no obstructive coronary arteries by improving coronary blood flow and lowering small-vessel resistance compared with a placebo.

Quick facts

PhasePhase 4
Study typeInterventional
Enrollment46 (estimated)
Ages18 Years and up
SexAll
SponsorVZW Cardiovascular Research Center Aalst Academic / other
Locations1 site (Aalst, Flanders)
Trial IDNCT06864234 on ClinicalTrials.gov

What this trial studies

Adults undergoing diagnostic coronary angiography who are found to have angina with no obstructive coronary arteries (ANOCA) will receive either metoprolol or a saline placebo and will have specialized intracoronary thermodilution measurements of absolute coronary flow and microvascular resistance before and after treatment. The main comparisons are changes in absolute coronary flow and microvascular resistance between the beta-blocker and placebo groups. Key eligibility requirements include FFR >0.80, no diameter stenosis >50%, TIMI 3 flow, and stable hemodynamics. Patients with heart failure symptoms, severe valvular disease, prior CABG, very low heart rate or blood pressure, or LVEF <40% are excluded.

Who should consider this trial

Good fit: Adults having diagnostic coronary angiography for angina who are found to have ANOCA (FFR >0.80, no stenosis >50%, TIMI 3 flow), with stable hemodynamics, heart rate ≥60 bpm, systolic blood pressure ≥100 mmHg, and LVEF ≥40% are ideal candidates.

Not a fit: Patients with clinical heart failure, severe valvular disease needing intervention, prior CABG, tortuous coronary anatomy, heart rate <60 bpm, systolic BP <100 mmHg, LVEF <40%, or inability to consent are excluded and unlikely to benefit from this protocol.

Why it matters

Potential benefit: If successful, this could show that an inexpensive, widely available beta-blocker improves coronary circulation in ANOCA and help guide treatment decisions to reduce symptoms.

How similar studies have performed: Guidelines and prior studies support beta-blocker use for symptomatic microvascular dysfunction, but direct evidence that beta-blockers improve absolute coronary flow and microvascular resistance is limited and has produced mixed results.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Patients undergoing diagnostic coronary angiography for suspected angina pectoris who are found to have ANOCA i.e. an FFR \>0.80 and no diameter stenosis \>50%
* Normal, TIMI 3 flow at angiography
* Stable haemodynamics

Exclusion Criteria:

* Clinical signs or symptoms of congestive heart failure
* Severe valvular heart disease requiring either surgical or percutaneous intervention
* History of coronary artery bypass grafting
* Tortuous coronary anatomy in which wire manipulation could be complex
* Heart rate \<60 beats per minute
* Systolic blood pressure \<100 mmHg
* Unable to give consent
* LVEF\<40%

Where this trial is running

Aalst, Flanders

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Coronary Arterial DiseaseAnginaMicrovascular Circulationanginacoronary artery diseaseabsolute coronary flowcontinuous intracoronary thermodilutionBeta-blockers
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.