Graft Patency and Clinical Outcomes Following Coronary Artery Bypass Grafting with Instrumented Radial Arteries

This study has two aims: 1. To evaluate the patency of instrumented radial arteries used for CABG, compared to non-instrumented radial arteries. 2. To evaluate the clinical outcomes of patients undergoing CABG with an instrumented radial artery, compared to those without an instrumented radial artery. Initially, patients will be recruited from the hospitals cardiac surgery database. Patients in the database who underwent surgery between January 2015 and December 2019 will be reviewed. Only those patients who had coronary artery bypass grafting with bilateral radial arteries will be included. For eligible patients, baseline data will be collected retrospectively from the hospital medical records and the hospital cardiac surgery database. Further data may be retrieved from other medical practitioners involved in their care. Information collected includes medical history, investigation results, pre-operative data, operation records, post operative data and longer term outcomes (see below for specific outcome data). Following review of the medical records, patients will be telephoned to seek clarification and further information as required. This will be a one off phone call, and will include facilitating completion of a Seattle Angina Questionnaire (short form, SAQ-7). The second part of the study, known as "patency follow up", involves conducting CT-coronary angiograms on a specific subset of patients. These patients are those who have an instrumented radial artery used as a coronary artery bypass graft. During the above "clinical follow up" phone call, patients will be assessed as to whether they are eligible for the "patency follow up" arm of the study. Eligible patients (see inclusion and exclusion criteria elsewhere in this document) will undergo a CT-coronary angiogram to evaluate the patency of the coronary artery bypass grafts. If eligible and willing to participate, patients will expect to undergo the CT-coronary angiogram within approximately 6-weeks. This scan will occur in Heidelberg, Victoria at I-MED Warringal and it is expected that the participant would require to be present for 1.5 - 2 hours duration.