Skip to main content
OpenTrials
Recruiting

NCT Number: NCT07386418

Study of Lesion-Specific Invasive Haemodynamic Angina Thresholds

ORBITA-SOLAR is an invasive physiological cardiac catheterisation study that aims to determine whether different coronary stenoses have different angina thresholds. The angina threshold is defined as the amount of coronary flow reduction required to reproduce symptoms. Sixty patients with symptoms of stable angina and 2 coronary artery stenoses amenable to percutaneous coronary intervention (PCI) will be recruited. This study will use intra-coronary balloon inflation during supine exercise on an ergometer to measure the fractional flow reserve (FFR) and non-hyperemic pressure ratio (NHPR) that relates to angina onset, in real time, at the location of each stenosis.

Recruiting

Interested in participating?

Request Info

Key information

Conditions

Angina (Stable) Angina Pectoris Angina, Stable Arterial Occlusive Diseases Arteriosclerosis Cardiovascular Diseases Chest Pain Coronary Artery Disease Coronary Artery Disease(CAD) Coronary Disease Heart Diseases Ischaemic Heart Disease (IHD) Myocardial Ischemia Neurologic Manifestations Pain Pathological Conditions, Signs and Symptoms Signs and Symptoms Vascular Diseases

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Mid and South Essex NHS Foundation Trust, Basildon, United Kingdom

Loading trial locations.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Eligibility for PCI due to angina or angina-equivalent symptoms on exertion
  • 2 severe epicardial stenoses in a major coronary artery, defined as:
  • ≥70% stenosis in a coronary artery with ≥2.5mm diameter, on invasive coronary angiography (ICA)
  • Severe stenosis in a vessel with ≥2.5mm diameter, on CTCA
  • Evidence of ischaemia on an invasive or non-invasive test, including:
  • Physiological test during invasive coronary angiography (ICA)
  • Dobutamine stress echocardiography (DSE)
  • Stress perfusion cardiac magnetic resonance (CMR)
  • Myocardial perfusion scintigraphy (MPS)
  • Fractional flow reserve computed-tomography (FFR-CT)

Exclusion criteria

  • Age <18 years
  • Acute coronary syndrome within 3 months
  • Previous coronary artery bypass graft
  • Significant left main stem disease
  • Single lesion amenable to PCI
  • Chronic total occlusion of the target artery
  • Moderate to severe valve disease
  • LVEF ≤40%, contraindication to PCI or drug-eluting stents
  • PCI performed with drug-eluting balloons without stenting
  • Contraindication to antiplatelet therapy
  • Contraindication to adenosine
  • Physical inability to exercise with an ergometer
  • Femoral artery access
  • Pregnancy
  • Inability to consent

Treatment and study plan

Percutaneous Coronary Intervention (PCI)

Procedure

Clinically indicated PCI for the management of stable angina

Measurement of the angina threshold

Diagnostic Test

Following stenting, the order in which to perform the angina threshold assessment at the location of each stent will be randomised. A non-compliant balloon with gradually be inflated over a pressure wire within the deployed stent to re-introduce stenosis. Simultaneously, the participant will exercise on a supine ergometer. At the point when angina is reproduced, the patient will rest and further balloon inflation will stop. Physiological measurements using the pressure wire will be taken with the inflated balloon in situ. This will represent the invasive physiological angina threshold. The balloon will then be deflated and removed. These steps will be repeated at the location of the second stent.

Primary outcomes

  1. Intra-individual difference in FFR and NHPR angina thresholds

    Time frame: Intra-procedural

    Difference in invasively measured physiological angina thresholds at the site of the 2 stents within each participant, stratified by vascular territory and lesion location along a vessel.

Secondary outcomes

  1. Correlation of the angina threshold with other invasive physiological assessments

    Time frame: Intra-procedural

    Including coronary artery disease pattern (focal, diffuse or mixed), presence of microvascular disease (IMR and CFR), extent of collateral flow (CFI), and pre- and post-PCI ischaemia (FFR and RFR)

  2. Correlation of the angina threshold with anatomical characteristics assessed with computed tomography coronary angiography (CTCA)

    Time frame: 14 days

    Including proportion of myocardial mass subtended (%), coronary artery territory (LAD, LCx, RCA), and lesion location along a vessel (proximal, mid, distal)

  3. Correlation of the angina threshold with anatomical characteristics assessed with quantitative coronary angiography (QCA)

    Time frame: 14 days

    Including lesion length (mm), minimum lumen diameter, (mm) percent diameter stenosis (%), and reference vessel diameter (mm)

  4. Correlation of the angina threshold with anatomical characteristics assessed with intravascular imaging

    Time frame: Intra-procedural

    Including lesion length (mm), pre-PCI minimum lumen area (mm2), post-PCI minimum stent area (mm2), reference vessel cross-sectional area (mm2), plaque characteristics (lipid, fibrotic, calcific)

  5. Correlation of the angina threshold with features on a stress perfusion cardiac magnetic resonance imaging (CMR) scan

    Time frame: 14 days

    Including myocardial perfusion reserve (MPR), number of segments of infarcted myocardium, and percentage mural infarct depth (%)

  6. Correlation of the angina threshold with baseline symptoms, quality of life and pain perception

    Time frame: 14 days

    Assessed with the ORBITA-app and validated questionnaires (SAQ, EQ5D5L)

Study contacts

Contact information is provided by the study sponsor or research team.

Kayla Chiew, MBBS MRCP

CONTACT

[email protected]

020 7594 5735

Rasha Al-Lamee, MBBS PhD MRCP

CONTACT

[email protected]

020 7594 5735

Sponsors and collaborators

Lead sponsor

Imperial College London

Other

Collaborators

  • Chelsea and Westminster NHS Foundation Trust
  • Guy's and St Thomas' NHS Foundation Trust
  • Imperial College Healthcare NHS Trust
  • Liverpool Heart and Chest Hospital NHS Foundation Trust
  • Mid and South Essex NHS Foundation Trust
  • Royal Free Hospital NHS Foundation Trust
  • St George's University Hospitals NHS Foundation Trust
  • University Hospitals Dorset NHS Foundation Trust

Registry information

Acronym: ORBITA-SOLAR

Important dates

Study start
2026
Primary completion
2028
Study completion
2028
First posted
Feb 4, 2026
Registry last updated
Jun 26, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.