What does my participation involve?
- Introduction
You may be invited to this research project because you have been scheduled for a type of surgical procedure called Coronary Artery Bypass Graft (CABG) surgery. Bypass surgery of the heart is a procedure to restore normal blood flow past an obstructed (blocked) artery to the heart. A vein or an artery can be used as part of this procedure.
This research project is testing a new treatment for CABG surgery. The new treatment is called Total Arterial Revascularisation.
Participants will be randomised to receive or not receive Total Arterial Revascularisation.
2 What is the purpose of this research?
Coronary artery disease affects 4 million Australians each year and occurs in patients who often have other medical conditions. Coronary artery disease involves narrowing the inside of the blood vessels (coronary arteries) that supply blood to your heart. The surgical treatment is Coronary Artery Bypass Graft surgery (CABG). During this surgery, a graft (hollow tube) is used to ‘bypass’ the blockage in a coronary artery, thus improving the blood supply to the heart tissues.
There are two main types of grafts – arterial and venous. Arterial grafts are when an artery is taken from another part of the body and used to bypass the blockage in the heart. Venous grafts are when a vein is taken from another part of the body and used to bypass the blockage. Both the use of arteries and grafts are commonly used in CABG worldwide.
One of the complications of CABG is the failure of bypass grafts (i.e. over time, the artery or vein graft does not remain open (patent)). Failure of grafts can lead to reduced blood flow to the heart tissue. It is not known whether arterial or venous grafts differ in how long they remain patent. This is what this study is aiming to find out. This multi-centre randomised trial proposes the exclusive use of arterial grafts (total arterial revascularisation, TAR) in one group versus using one or more vein grafts with additional arterial grafts in the second group. We will measure the grafts using a specialized CT scan to detect differences between the two groups.
This trial will be carried out at 17 centres across Australia.
This research has been initiated by the study doctor, Professor Alistair Royse.
This research has been funded by the Medical Research Future Fund (MRFF) Grant.
This research is being conducted by The Department of Surgery, University of Melbourne and sponsored in Australia by Melbourne Health.
3 What does participation in this research involve?
You will be participating in a randomised controlled research project. Sometimes we do not know which treatment is best for treating a condition. To find out, we need to compare different treatments. We put people into groups and give each group a different treatment. The results are compared to see if one is better. To ensure the groups are the same, each participant is put into a group by chance (random).
Currently, there are two different surgical techniques used in CABG surgery – one uses only arteries as grafts (“Total Arterial”, “TA”). In contrast, the other uses a combination of arteries and veins for grafts (“Non-Total Arterial”, “Non-TAR”). Both these surgical techniques are seen as ‘standard of care’ – ie both techniques are accepted surgical techniques for CABG surgery. They are considered ‘equipoise’ – that is, no increased risk is associated with using one or other graft type.
Participants will be randomised (1:1 allocation) to receive or not receive total arterial revascularisation (TAR) during CABG surgery. The surgeon will use only arterial grafts in patients randomised to the TAR group. In patients randomised to the Non-TAR group. The surgeon will use a combination of arterial and vein grafts. All preoperative, intraoperative, and postoperative management, investigations or operative reconstructive techniques are according to the surgeon and institutional practice, except for the randomised allocation.
This research project has been designed to ensure the researchers interpret the results fairly and appropriately and prevent study doctors or participants from jumping to conclusions.
There are no additional costs associated with participating in this research project, nor will you be paid. All medication, tests and medical care required as part of the research project will be provided free of charge.
Your local doctor should be advised of your decision to participate in this research project. If you have a local doctor, we strongly recommend informing them of your participation in this research project.
4 What do I have to do?
If you agree to participate in the study, the research personnel will collect some baseline data. This will include reviewing your preoperative information by a researcher (a chart review), followed by a 10-minute clinical assessment. This assessment will include recording your vital signs (blood pressure, heart rate etc.) and listening to your chest. Follow-up assessments will be face-to-face (in person) while you are in hospital. Subsequent follow-up assessments will be by telephone, video call or in person.
During this trial, you will be asked to take part in the following activities:
- Verbal Surveys performed by the researcher and you:
- Postoperative Quality Recovery Survey (PostoPQRS)– This is performed preoperatively and then again at six postoperative time points (day 1, 3-5, 30 days, 3 months, six months and two years). The PostopQRS consists of a 5-minute verbal survey, which will be conducted by researchers face-to-face whilst you’re in hospital, and via telephone once you have been discharged. These surveys will coincide with clinical assessments where possible.
- Functional Difficulties Questionnaire and Lawton and Brody Instrument Activities of Daily Living Surveys – These surveys are performed preoperatively, and then at six months postoperatively.
- EQ-5D-5L Survey – This survey is performed preoperatively, and then at two postoperative time points (3 months and six months)
These surveys are verbal questionnaires where a researcher will ask you a set of standard questions, either face to face whilst you are in hospital or attending a scheduled postoperative visit, or on the telephone once you have been discharged. It will take approximately 5-10 minutes to complete all the questions, depending on whether one or all surveys are performed. A researcher will ask you questions about how you can perform daily living activities and how you view your comfort, quality of life, and overall recovery. The researcher will record your answers.
- Clinical follow-up to assess the outcome will be at six monthly intervals (ie at 6, 12, 18 and 24 months post-surgery). This involves you attending a face-to-face consultation, which will take approximately 15 minutes and involve a brief standard recording of your vitals and physical assessment. These will coincide with any scheduled postoperative visits that you will have with your surgeon.
- Computer Tomography Coronary angiography (CTCA) assessments will be done at 3 and 24 months. – This involves attending a local medical imaging centre to undergo a 15-minute scan (Computer Tomography, or CT scan) of the blood supply to your heart. We will aim to coincide these assessments with any other trial activities to minimise inconvenience to you. The CTCA scan involves inserting a small cannula into a vein in your hand or arm, injecting some contrast (or dye) into the vein, and then imaging this dye as it flows through your heart using the CT machine. The CT is a non-invasive scan (or picture) where you lie down on the CT bed, have the dye injected and remain lying as the scan is performed.
5 Other relevant information about the research project
A total of 1000 participants will be recruited for this study in Australia.
6 What happens when the research project ends?
Participants will be provided with a summary of the results when the research project is completed. This will be by the study webpage (TotalArterial.org) and communication of study findings via email/standard postage. Study findings will also be published in scientific journals and presented at conferences.