RecruitingOBSERVATIONAL

Graft Failure and Consequences of Coronary Artery Bypass Graft Surgery

This study is investigating why heart bypass grafts, which are used to fix blocked heart arteries, sometimes stop working. Bypass surgery is a common heart operation, but unfortunately, these grafts can fail, potentially leading to heart attacks or strokes. We know that certain grafts (vein grafts) can narrow over time, and treating this narrowing can be tricky. This study aims to understand the reasons behind these complications. Researchers will use special body scans and blood tests to look closely at what happens inside the grafts, as well as the heart, brain, and other body parts, after bypass surgery. This will help us learn more about preventing these issues in the future.

At a glance

Status

Recruiting

Sponsor

University of Edinburgh

Enrolment target

Start

28 Mar 2025

Estimated completion

06 Aug 2027

Coronary Artery Bypass Graft Failure Coronary Artery Bypass Graft Coronary Artery Bypass Graft Surgery (CABG)

What is this study about?

When people have heart bypass surgery (also known as CABG surgery), surgeons use healthy blood vessels (called 'grafts') from other parts of the body to create new paths for blood to flow around blocked arteries in the heart. This helps the heart get the blood and oxygen it needs. It's a very common operation that saves lives.

However, sometimes these grafts, especially those made from veins, can narrow or fail over time. When this happens, it can lead to serious problems like heart attacks or strokes. Unfortunately, it's often difficult to treat failed grafts, as repeat surgery can be risky, and trying to open them with stents doesn't always work. At the moment, we don't fully understand why these grafts sometimes fail or why these complications happen.

This study hopes to shed light on these important questions. Researchers will use advanced imaging techniques—special whole-body scans called PET-CT scans—along with blood tests, to get a clear picture of what's happening inside the grafts, the heart, the brain, and the rest of the body after bypass surgery. By understanding the causes of graft failure and other complications, the goal is to ultimately improve care and outcomes for people who have had, or will have, bypass surgery.

Key takeaways

This study investigates why heart bypass grafts sometimes fail.
It uses special scans and blood tests to understand heart health after surgery.
Two groups of patients are being recruited: recent bypass patients and those with older grafts showing symptoms.
Participation involves PET-CT scans, heart ultrasounds, and blood tests.
The findings aim to improve future outcomes for bypass surgery patients.

Who may be eligible?

This study is looking for two main groups of people. The first group includes adults aged 18 and over who are about to have heart bypass surgery where at least one vein graft will be used. This will help researchers see what happens to the grafts shortly after surgery.

The second group includes adults aged 18 and over who had heart bypass surgery at least five years ago, received two or more vein grafts, and are currently experiencing symptoms that suggest their grafts might be having problems. These symptoms have led their doctors to refer them for further heart scans.

There are also some reasons why you might not be able to join the study. For example, if you have a very serious kidney problem, are taking medicines that suppress your immune system, are pregnant or breastfeeding, or have certain allergies or medical conditions that make scans unsafe for you. You also need to be able to lie flat for the scans and be able to understand and agree to take part.

Quick self-check

Are you 18 years or older?
Have you recently had, or are you about to have, heart bypass surgery with a vein graft?
Or, did you have bypass surgery at least 5 years ago, with vein grafts, and are you now experiencing heart-related symptoms?
Are you able to lie flat for scans?
Are you not pregnant or breastfeeding?
Do you not have very severe kidney disease or take immune-suppressing medicines?

This is a guide only — the research team will confirm whether you can take part.

What does participation involve?

If you decide to join this study, it will last for a total of 36 months, which is three years. During this time, you'll have specific appointments and tests.

These will include a special full-body scan called a PET-CT scan, which uses a small amount of a safe tracing substance to help researchers see what's happening inside your body. You'll also have an ultrasound scan of your heart, called an echocardiogram, which uses sound waves to create pictures of your heart.

In addition, we'll ask for a blood sample, which is about four tablespoons (60 mL) of blood. Some of this blood will be tested straight away, and any unused blood will be stored for future essential research studies that have been approved by an ethics committee. You'll also have a general check-up with the study team.

Potential risks and benefits

Participating in this study might not directly benefit your health immediately, but the information we gather could greatly help improve understanding and care for future bypass surgery patients. Potential risks are generally low. The PET-CT scan involves a small amount of radiation, similar to other medical scans, and there's a minor risk associated with the blood draw, like bruising. You will also need to be able to comfortably lie still for the scans. Remember, you can choose to leave the study at any time, for any reason, without it affecting your usual medical care.

Locations (1)

Royal Infirmary of Edinburgh
Edinburgh, United Kingdom· Recruiting

Common questions

What is a heart bypass graft?

It's a healthy blood vessel taken from another part of your body and used to create a new path for blood to flow around blocked arteries in your heart.

What is a PET-CT scan?

It's a special type of scan that combines two imaging techniques to create detailed pictures inside your body, helping doctors see how organs are working.

Will I have to take any new medications?

No, this study does not involve taking any new medications. We are observing what happens, not testing a new drug.

How long will the study last for me?

The study itself lasts 36 months, and you'll have specific appointments and tests during that time, though you won't be in clinic for 36 months straight.

Can I stop participating if I change my mind?

Yes, you are free to withdraw from the study at any time, for any reason, without it affecting your medical care.

How to find out more

Laura E Clark, BSc, MBChB, MRCS(Ed)

lclark15@ed.ac.uk +447717478087 Official trial record

Always speak to your GP or specialist before deciding to take part in a study.