Conservative Non-Invasive Versus Routine Invasive Management in Coronary Artery Bypass Surgery Patients with Non ST Elevation Elevation Acute Coronary Syndrome

Background: Most coronary artery bypass grafts (CABG) are diseased or blocked within 10 years of surgery meaning CABG survivors have an ever increasing risk of recurrent angina, heart attack and death. Given the large number of CABG survivors in the United Kingdom (UK), and the complexities of their clinical management, their heart health problems and related treatment are an increasing challenge in the UK National Health Service (NHS) and worldwide. There is considerable controversy in the NHS and internationally about how to best manage patients with prior CABG and unstable angina / non-ST elevation acute coronary syndromes (NSTE-ACS). This is because there is no robust evidence to inform treatment practices or clinical guidelines since, historically, these patients have been excluded from randomised trials. This is the rationale for our study. Aims: Our overall aim is to undertake a clinical trial of conservative non-invasive management with optimal drug therapy versus routine invasive management in NSTE-ACS patients with prior CABG during routine clinical care in NHS hospitals across the UK. Our trial is a proof-of-concept study of feasibility, safety, potential efficacy and health economics. Hypothesis: A routine invasive approach in NSTE-ACS patients with prior CABG will not be superior to a conservative non-invasive approach with optimal medical therapy. Design: The pilot study will involve 60 patients recruited in large urban hospitals (Western Infirmary, Glasgow Royal Infirmary) and district general hospitals (Royal Alexandra Hospital, Royal Blackburn Hospital (RBH)) to reflect usual practice in the UK. One of these hospitals (RBH) has an on-site cardiac catheterization laboratory, whereas the other hospitals refer patients who have been triaged for invasive management to the regional cardiothoracic centre (the Golden Jubilee National Hospital). In this proof of concept study, the investigators aim to gather information about screening, recruitment, ran