Coronary Artery BypassNCT06800430
Graft Failure and Consequences of Coronary Artery Bypass Graft Surgery
An observational study of Coronary Artery Bypass and Graft Failure, run by University of Edinburgh at 1 site in United Kingdom.
Trial summary
Coronary artery bypass graft (CABG) surgery is the commonest type of heart operation performed. During this, arteries or veins (termed 'grafts') are used to supply blood around blockages within the blood vessels that supply the heart. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Coronary Artery Bypass, Graft Failure, Coronary Artery Bypass Graft
- What is being tested?
- Hybrid [18F]-GP1, [68Ga]-DOTATATE, [68Ga]-FAPI total-body positron emission tomography and coronary computed tomography coronary angiography
- Type of treatment
- Surgery or procedure
- How many people
- 70 participants
- Where
- 1 siteUnited Kingdom
- Study dates
- 28 Mar 2025to 6 Aug 2027
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: We will recruit two populations of patients following CABG surgery. Participants will be prospectively recruited following CABG surgery (cohort 1), or identification of clinically suspected saphenous vein graft failure (cohort 2). Recruitment will for both cohorts will be from a single, tertiary centre (Royal Infirmary of Edinburgh).
Who may be able to join
- Cohort 1: Patients undergoing CABG surgery
- Males and females over 18 years of age
- Patients undergoing CABG surgery for multivessel coronary artery disease, who receive at least one saphenous vein graft
- Cohort 2: Patients with symptomatic saphenous vein graft vasculopathy
- Males and females over 18 years of age
- Patients who underwent CABG surgery ≥ 5 years prior to recruitment for multivessel disease and received 2 or more saphenous vein grafts
- Referred for invasive coronary angiography due to recurrent symptoms and with a high suspicion of graft vasculopathy
Who cannot join
- Patients with a life expectancy of < 2 years
- Renal failure (estimated glomerular filtration rate <30 mL/min/1.73 m2)
- Patients on immunosuppressive therapies
- Females of child-bearing age who are pregnant or breastfeeding,
- Known allergy or contraindications to iodinated contrast or radiotracer
- Patients who are unable to tolerate the supine position
- Patients who are unable to provide informed consent
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
David E Newby, BSc (Hons) PhD BM DM DSc FRCP contact
United Kingdom1 site, 1 recruiting
- Recruiting
Royal Infirmary of Edinburgh
Edinburgh, Midlothian, EH16 4SA
Laura E Clark, MBChB BSc(Hons), +447717478087, laura.clark8@nhs.scot
Laura E Clark, MBChB BSC(Hons)
About this study
Official title: Vein Graft Failure and Cardiovascular Consequences of Coronary Artery Bypass Graft Surgery
Coronary artery bypass graft (CABG) surgery is the commonest type of heart operation performed. During this, arteries or veins (termed 'grafts') are used to supply blood around blockages within the blood vessels that supply the heart. Unfortunately, these grafts can sometimes fail, and patients can also experience complications like heart attacks and strokes, after surgery. It is known that vein grafts are more likely to narrow over time. Additionally, treating vein graft failure is very challenging, as repeat surgery is riskier and procedures to stent open the veins can also fail. However, it is not fully understood why these complications occur.
In this study, the investigators will use an imaging technique called a total-body Positron Emission Tomography (PET) scan. This uses special radioactive dyes (radiotracers) to look at what is happening inside vein grafts. With this technique, the investigators will also be able to see what is happening to the heart, brain and wider parts of the body after CABG surgery.
Read more
This study will aim to recruit 70 participants in total (maximum 150). 40 (maximum of 120) of these participants will have recently undergone CABG surgery and received ≥1 vein graft. The remaining 30 will have undergone CABG surgery ≥5 years ago and will have symptoms suggestive of vein graft failure.
The study will last a total of 36 months and will involve participants undertaking the following assessments:
- Total-body Positron Emission Tomography and Computed Tomography (PET-CT) scan
- Ultrasound scan of the heart (echocardiogram)
- A blood test - up to four tablespoons (60 mL) of blood will be taken for immediate testing and the remainder will be stored for future ethically approved studies.
Read the detailed description
This is an observational cohort study investigating the role of inflammation, thrombosis and fibrosis in saphenous vein graft failure following CABG surgery. The presence and distribution of these processes will be examined in one cohort overtime (immediately following surgery and at 1 year-follow up) and at one time-point in a second cohort with clinically suspected vein graft failure.
Participants in both cohorts will undergo clinical review (including blood sampling), transthoracic echocardiogram and combined total-body positron emission tomography computed tomography (PET-CT) imaging, with CT coronary angiography.
- Conditions
- Coronary Artery Bypass, Graft Failure, Coronary Artery Bypass Graft, Coronary Artery Bypass Graft Surgery (CABG)
- Being tested
- Hybrid [18F]-GP1, [68Ga]-DOTATATE, [68Ga]-FAPI total-body positron emission tomography and coronary computed tomography coronary angiography
- Keywords
- CABG, graft failure, coronary artery bypass, cardiovascular, heart surgery, cardiac surgery, coronary artery bypass graft, cardiovascular disease, heart disease, positron emission tomography
- Medical subject headings
- Cardiovascular Diseases, Heart Diseases
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Hybrid [18F]-GP1, [68Ga]-DOTATATE, [68Ga]-FAPI total-body positron emission tomography and coronary computed tomography coronary angiographyRadiation
Patients undergo hybrid [18F]-GP1, [68Ga]-FAPI and [68Ga]-DOTATATE total body PET-CT imaging (Biograph Vision Quadra, Siemens) and contrast-enhanced electrocardiogram gated CT coronary angiogram (CTCA), within 28 days (+/- 28 days) of their CABG surgery and again at 12 month follow-up.
Hybrid [18F]-GP1, [68Ga]-DOTATATE, [68Ga]-FAPI total-body positron emission tomography and coronary computed tomography coronary angiographyRadiation
Patients undergo hybrid [18F]-GP1, [68Ga]-FAPI and [68Ga]-DOTATATE total body PET-CT imaging (Biograph Vision Quadra, Siemens) and contrast-enhanced electrocardiogram gated CT coronary angiogram (CTCA), prior to their clinical invasive coronary angiography.
| Study group | Role | What they receive |
|---|---|---|
| Cohort 1: Patients undergoing CABG surgery | 40 patients (maximum 120) undergoing CABG surgery with multi-vessel disease and at least one saphenous vein graft. Receives: Radiation: Hybrid [18F]-GP1, [68Ga]-DOTATATE, [68Ga]-FAPI total-body positron emission tomography and coronary computed tomography coronary angiography | |
| Cohort 2: Patients with symptomatic saphenous vein graft vasculopathy | 30 patients with prior CABG surgery (at least 5 years previously) with multi-vessel disease and two or more saphenous vein grafts, who have been referred for invasive coronary angiography due to symptoms and with a high suspicion of graft vasculopathy. Receives: Radiation: Hybrid [18F]-GP1, [68Ga]-DOTATATE, [68Ga]-FAPI total-body positron emission tomography and coronary computed tomography coronary angiography |
What is being measured
The primary outcome is the main question the study is designed to answer.
Platelet activation
The degree and location of platelet activation within saphenous vein grafts, measured using standard uptake values and tissue-to-background ratios of [18F]-GP1.
Measured: 3 years
Fibroblast activation
The degree and location of fibroblast activation within saphenous vein grafts, measured using standard uptake values and tissue-to-background ratios of [68Ga]-FAPI.
Measured: 3 years
Macrophage activation
The degree and location of macrophage activation within saphenous vein grafts, measured using standard uptake values and tissue-to-background ratios of [68Ga]-DOTATATE.
Measured: 3 years
Secondary outcomes (1)
Systemic cardiovascular disease
The secondary endpoints will include the presence of systemic thrombotic, fibrotic or inflammatory cardiovascular disease, assessed through biomarker and CT imaging analyses.
Measured: 3 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted30 Jan 2025
- Study start28 Mar 2025
- Primary completion28 Mar 2027 (estimated)
- Study completion6 Aug 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Coronary Artery BypassStudies of the same condition, open and under way.
- More trials run by University of EdinburghThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 70 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Edinburgh
- Sponsor type
- University, hospital or other
- Collaborators
- NHS Lothian
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06800430
- Sponsor's protocol ID
- AC24158
- Other IDs
- SS/CH/09/002
- Status last verified
- Apr 2026
- First submitted
- 22 Jan 2025
- Last updated
- 20 Apr 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 20 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Vein Graft Failure and Cardiovascular Consequences of Coronary Artery Bypass Graft Surgery
- ClinicalTrials.gov ID
- NCT06800430
- Acronym / sponsor ID
- AC24158
- Conditions
- Coronary Artery Bypass, Graft Failure, Coronary Artery Bypass Graft, Coronary Artery Bypass Graft Surgery (CABG)
- Keywords
- CABG, graft failure, coronary artery bypass, cardiovascular, heart surgery, cardiac surgery, coronary artery bypass graft, cardiovascular disease
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 70 participants (estimated)
- Lead sponsor
- University of EdinburghUniversity, hospital or other
- Collaborators
- NHS Lothian
- Study start
- 28 Mar 2025 (actual)
- Primary completion
- 28 Mar 2027 (estimated)
- Study completion
- 6 Aug 2027 (estimated)
- First posted
- 30 Jan 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Coronary artery bypass graft (CABG) surgery is the commonest type of heart operation performed. During this, arteries or veins (termed 'grafts') are used to supply blood around blockages within the blood vessels that supply the heart. Unfortunately, these grafts can sometimes fail, and patients can also experience complications like heart attacks and strokes, after surgery. It is known that vein grafts are more likely to narrow over time. Additionally, treating vein graft failure is very challenging, as repeat surgery is riskier and procedures to stent open the veins can also fail. However, it is not fully understood why these complications occur.
In this study, the investigators will use an imaging technique called a total-body Positron Emission Tomography (PET) scan. This uses special radioactive dyes (radiotracers) to look at what is happening inside vein grafts. With this technique, the investigators will also be able to see what is happening to the heart, brain and wider parts of the body after CABG surgery.
This study will aim to recruit 70 participants in total (maximum 150). 40 (maximum of 120) of these participants will have recently undergone CABG surgery and received ≥1 vein graft. The remaining 30 will have undergone CABG surgery ≥5 years ago and will have symptoms suggestive of vein graft failure.
The study will last a total of 36 months and will involve participants undertaking the following assessments:
- Total-body Positron Emission Tomography and Computed Tomography (PET-CT) scan
- Ultrasound scan of the heart (echocardiogram)
- A blood test - up to four tablespoons (60 mL) of blood will be taken for immediate testing and the remainder will be stored for future ethically approved studies.
Detailed description
This is an observational cohort study investigating the role of inflammation, thrombosis and fibrosis in saphenous vein graft failure following CABG surgery. The presence and distribution of these processes will be examined in one cohort overtime (immediately following surgery and at 1 year-follow up) and at one time-point in a second cohort with clinically suspected vein graft failure.
Participants in both cohorts will undergo clinical review (including blood sampling), transthoracic echocardiogram and combined total-body positron emission tomography computed tomography (PET-CT) imaging, with CT coronary angiography.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Cohort 1: Patients undergoing CABG surgery | – | Radiation: Hybrid [18F]-GP1, [68Ga]-DOTATATE, [68Ga]-FAPI total-body positron emission tomography and coronary computed tomography coronary angiography40 patients (maximum 120) undergoing CABG surgery with multi-vessel disease and at least one saphenous vein graft. |
| Cohort 2: Patients with symptomatic saphenous vein graft vasculopathy | – | Radiation: Hybrid [18F]-GP1, [68Ga]-DOTATATE, [68Ga]-FAPI total-body positron emission tomography and coronary computed tomography coronary angiography30 patients with prior CABG surgery (at least 5 years previously) with multi-vessel disease and two or more saphenous vein grafts, who have been referred for invasive coronary angiography due to symptoms and with a high suspicion of graft vasculopathy. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- We will recruit two populations of patients following CABG surgery. Participants will be prospectively recruited following CABG surgery (cohort 1), or identification of clinically suspected saphenous vein graft failure (cohort 2). Recruitment will for both cohorts will be from a single, tertiary centre (Royal Infirmary of Edinburgh).
Key inclusion criteria (7 listed)
- Cohort 1: Patients undergoing CABG surgery
- Males and females over 18 years of age
- Patients undergoing CABG surgery for multivessel coronary artery disease, who receive at least one saphenous vein graft
- Cohort 2: Patients with symptomatic saphenous vein graft vasculopathy
- Males and females over 18 years of age
Key exclusion criteria (7 listed)
- Patients with a life expectancy of < 2 years
- Renal failure (estimated glomerular filtration rate <30 mL/min/1.73 m2)
- Patients on immunosuppressive therapies
- Females of child-bearing age who are pregnant or breastfeeding,
- Known allergy or contraindications to iodinated contrast or radiotracer
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Hybrid [18F]-GP1, [68Ga]-DOTATATE, [68Ga]-FAPI total-body positron emission tomography and coronary computed tomography coronary angiographyPatients undergo hybrid [18F]-GP1, [68Ga]-FAPI and [68Ga]-DOTATATE total body PET-CT imaging (Biograph Vision Quadra, Siemens) and contrast-enhanced electrocardiogram gated CT coronary angiogram (CTCA), within 28 days (+/- 28 days) of their CABG surgery and again at 12 month follow-up. | Radiation | Cohort 1: Patients undergoing CABG surgery |
| Hybrid [18F]-GP1, [68Ga]-DOTATATE, [68Ga]-FAPI total-body positron emission tomography and coronary computed tomography coronary angiographyPatients undergo hybrid [18F]-GP1, [68Ga]-FAPI and [68Ga]-DOTATATE total body PET-CT imaging (Biograph Vision Quadra, Siemens) and contrast-enhanced electrocardiogram gated CT coronary angiogram (CTCA), prior to their clinical invasive coronary angiography. | Radiation | Cohort 2: Patients with symptomatic saphenous vein graft vasculopathy |
Primary outcome
Platelet activation
Time frame: 3 years
The degree and location of platelet activation within saphenous vein grafts, measured using standard uptake values and tissue-to-background ratios of [18F]-GP1.
Fibroblast activation
Time frame: 3 years
The degree and location of fibroblast activation within saphenous vein grafts, measured using standard uptake values and tissue-to-background ratios of [68Ga]-FAPI.
Macrophage activation
Time frame: 3 years
The degree and location of macrophage activation within saphenous vein grafts, measured using standard uptake values and tissue-to-background ratios of [68Ga]-DOTATATE.
1 secondary outcome
Systemic cardiovascular disease
Time frame: 3 years
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 20 Apr 2026.
- Individual participant dataSharing planned: No
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Coronary Artery Bypass Graft (CABG)
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
David E Newby, BSc (Hons) PhD BM DM DSc FRCP contact
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Coronary Artery Bypass and Graft Failure, run by University of Edinburgh at 1 site in United Kingdom.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 20 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Laura E Clark, BSc, MBChB, MRCS(Ed) (+447717478087, lclark15@ed.ac.uk), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Platelet activation (time frame: 3 years). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 20 Apr 2026.