Condition category
Circulatory System
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status

Plain English Summary

Background and study aims
Coronary artery disease (CAD) and its consequences are the leading cause of death and disease in the Western world, leading to major healthcare and economic burdens. CAD is the thickening of the walls of the coronary arteries that supply blood to the heart, caused by the build-up of fatty deposits in these blood vessels. Percutaneous coronary intervention (PCI) is a routine and widely used treatment to reopen narrowed or blocked coronary arteries. PCI is usually performed by feeding a hollow wire (catheter) through the blood vessels to the site of the blockage, inflating a balloon at the tip of the catheter to stretch the artery wall vessel and then placing an expandable metal tube (stent) at the site of the blockage. The stent stays in the wall of the artery in order to keep the artery wall stretched and allow blood to flow freely through the artery. Tools that can take pictures of the inside of the coronary arteries, have contributed substantially to our understanding of the how best to place a stent. Optical coherence technology (OCT) is a method for taking pictures of the inside of the coronary arteries, which provides an image with much greater resolution than current alternatives (e.g. intravascular ultrasound). The definition of the OCT images is at least ten times greater than with ultrasound, which enables very detailed imaging of the artery wall, the fatty deposits and, once placed, the stent. To date, there have been no studies of the usefulness of OCT for improving stent placement and the effectiveness of PCI. In this study we wish to assess whether routine use of OCT to guide stent placement will lead to improved stent placement.

Who can participate?
Patients aged 30 to 90 who are undergoing PCI for the treatment of CAD or acute coronary syndrome

What does the study involve?
Participants are randomly allocated to undergo either angiographically guided or OCT-guided stent placement. Angiographically guided stent placement is the standard care pathway, where a type of X-ray is used to examine the blood vessels. OCT-guided stent placement involves taking pictures of the inside of the coronary arteries to guide decisions about the size and type of stent to use. All patients receive standard hospital follow up. 12 months after their procedure all patients complete a questionnaire.

What are the possible benefits and risks of participating?
Not provided at time of registration

Where is the study run from?
University of Bristol (UK)

When is the study starting and how long is it expected to run for?
March 2014 to May 2018

Who is funding the study?
National Institute for Health Research (UK)

Who is the main contact?
Lucy Culliford

Trial website

Contact information



Primary contact

Dr Lucy Culliford


Contact details

CTEU Bristol
Level 7 Zone A Queens Building
Bristol Royal Infirmary
Marlborough Street
United Kingdom
+44 (0)117 342 2526

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Optical Coherence Tomography to guIde stent placeMent durIng percutaneouS coronary intErvention: a randomised controlled trial



Study hypothesis

The aim of this study is to assess whether routine use of optical coherence technology (OCT) to guide stent placement will lead to improved stent placement and improved clinical outcomes at one year for people with coronary heart disease (CHD).

Ethics approval

West Midlands -Coventry and Warwick NRES committee, 25/02/2015, ref: 15/WM/0075E

Study design

Randomised; Interventional; Design type: Treatment

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use contact details to request a patient information sheet


Topic: Cardiovascular disease; Subtopic: Cardiovascular (all Subtopics); Disease: Cardiovascular


Following the consenting process the intervention begins in the Catheter laboratory:

1. Angiographically guided stent placement: This is the standard care pathway, the patient has their stent placed using standard treatment plan, once the clinician has stated that they have completed deployment the OCT catheter is taken past the stent(s,) this is known as a 'pullback', to visually record the inside of the lumen. The procedure ends. The patient has standard care and is discharged.
Duration is approximately 5 minutes longer than standard care.
2. OCT guided stent placement: After the standard angiogram and review of the lesions, the OCT catheter is used to visualise the inside of the lumen, the clinician uses the images to guide their decisions about size and type of stent used. The catheter is used again to check stent placement, the clinician makes any adjustments or corrections to the stent placement and if necessary another pullback is made to check the stent. Once the clinician is content, that the deployment is complete, a reference pullback occurs.

The procedure ends. The patient has standard care and is discharged. Duration is approximately 10 minutes longer than standard care. All patients receive standard hospital follow up. 12 months after their procedure all patients will receive a trial questionnaire.

Intervention type



Drug names

Primary outcome measure

To estimate the difference in minimal luminal area (MLA) immediately after the completion of PCI between the OCT-guided and the angiographically guided PCI groups. This outcome will be assessed by processing the digitally stored OCT images.

Secondary outcome measures

In the OCT-guided and angiographically guided groups:
1. To quantify and compare the prevalence of strut apposition, edge dissection and plaque prolapse. This will be determined from the images taken to assess the primary endpoint
2. To compare the nature and extent of additional interventions indicated from OCT images of the deployed stent, such as additional balloon dilations or further stenting
3. To quantify and compare the PCI procedure duration, the volume of contrast used and the X-ray dosage
4. To quantify and compare the number of major clinical events at 12 months follow-up

In OCT-guided group only:
Information about how the pre-deployment OCT images informed the choice of treatment strategy and stent

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)

Objectives no longer viable


Participant inclusion criteria

A participant may enter study if ALL of the following apply:
1. Adults of either sex aged 30 to 90 years who are undergoing EITHER,
1.1. Elective PCI for the treatment of CAD OR
1.2. Urgent PCI for the treatment of ACS
2. Patients who are willing and able to give written informed consent for participation in the study
3. Patients who are anticipated to have at least a 20 mm stent length in at least one lesion

Participant type


Age group




Target number of participants

Planned Sample Size: 128; UK Sample Size: 128

Participant exclusion criteria

A participant may not enter study if ANY of the following apply:
1. Patients unable to provide written informed consent.
2. Patient undergoing emergency PCI
3. Patients that have had previous PCI within the target vessel.
4. Women who are pregnant or breast feeding
5. Haemodynamic instability
6. Renal impairment (eGFR =50 ml/min)
7. Multivessel PCI (>2 vessels) during a single procedure
8. Left main stem disease
9. Estimated angiographic vessel calibre <2.5mm or >4.5mm
10. Additional significant disease (>50% stenosis) in same vessel proximal or distal to culprit lesion
11. Target vessels / lesions of excessive tortuosity
12. Patients participating in another interventional study

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Bristol Heart Institute
United Kingdom

Sponsor information


University Hospitals Bristol NHS Foundation Trust

Sponsor details

Research & Development
Upper Maudlin Street
United Kingdom

Sponsor type

Hospital/treatment centre



Funder type


Funder name

National Institute for Health Research

Alternative name(s)


Funding Body Type

government organisation

Funding Body Subtype

National government


United Kingdom

Results and Publications

Publication and dissemination plan

The findings will be disseminated by usual academic channels, i.e. presentation at international meetings, as well as by peer-reviewed publications and through patient organisations and newsletters to patients, where available. We intend to publish as soon as possible.

Intention to publish date

Participant level data

Available on request

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

04/06/2019: This trial formed part of the Bristol NIHR BRU. The proposed trial became redundant before it could be carried out because of software developments and the publication of other trials, primarily the DOCTORS trial. The researchers reviewed options for modifying the trial in November 2015, specifically an amended design based on a software upgrade that provides enhanced measurements. They decided not to pursue this re-designed trial because of the limited time remaining in the BRU award and the cost implications of the revised design. This summary was reported to the NIHR in their 2016 and 2017 reports. 21/05/2019: Internal review. 16/06/2016: Plain English summary added.