Senescence in Myocardial Infarction

The goal of this observational study is to compare the levels of aged-cell proteins in participants who have coronary artery bypass graft (CABG) surgery after a recent heart attack or to treat more stable heart disease. The main questions it aims to answer are: 1. To identify if there is an increased in aged-cell proteins in participants who have had a myocardial infarction and are having CABG surgery, compared to participants who are having CABG surgery for more stable heart disease. 2. To establish if levels of these aged-cell proteins can predict outcomes for these patients, and if they correlate with other markers of heart disease. The investigators will do this by taking blood samples and a sample of normally discarded heart tissue from each group of participants. This might help inform who is at the highest risk of developing heart disease and how patients recover from a heart attack.