ObjectivesTo characterise the variation in access to and outcomes of cardiac surgery for people in England.MethodsWe included people >18 years of age with a hospital admission for ischaemic heart disease (IHD) and heart valve disease (HVD) between 2010 and 2019. Within these populations, we identified patients who had coronary artery bypass graft (CABG) and/or valve surgery, respectively. We fitted logistic regression models to examine the effects of age, sex, ethnicity and socio-economic deprivation on having access to surgery and in-hospital mortality, 1-year mortality and hospital readmission.ResultsWe included 292,140 people, of whom 28% were women, 11% were from an ethnic minority and 17% were from the most deprived areas. Across all types of surgery, 1 in 5 patients are readmitted to hospital within 1 year, rising to almost 1 in 4 for valve surgery patients. Women, Black people and people living in the most deprived areas were less likely to have access to surgery (CABG: 59%, 32%, 35% less likely; valve: 31%, 33%, 39% less likely, respectively) and more likely to die within 1 year of surgery (CABG: 24%, 85%, 18% more likely, respectively; valve: 19% (women) and 10% (people from most deprived areas) more likely).ConclusionFemale sex, Black ethnicity, and economic deprivation are independently associated with limited access to cardiac surgery and higher post-surgery mortality. Actions are required to address these inequalities.WHAT IS ALREADY KNOWN ON THIS TOPICThere has been a marked improvement in short term (in hospital) outcomes of people having cardiac surgery. It is not clear if this translates to improvement in mid- and long-term outcomes and how these differ by demographic and socio-economic factors.WHAT THIS STUDY ADDSAcross all types of cardiac surgery, 1 in 5 patients are readmitted to hospital within 1 year of surgery, rising to almost 1 in 4 for valve surgery patients.While in hospital mortality has decreased markedly since 2010 (by 20%), 1 year mortality and hospital readmission remained largely unchanged.Women, people of Black ethnicity and people from the most socially deprived areas were less likely to be offered cardiac surgery and more likely to die and be readmitted to hospital in the year after surgery.HOW THIS STUDY MIGHT AFFECT RESEARCH, PRACTICE OR POLICYTargeted interventions are required across the cardiovascular medicine pathway to improve mid- and long-term outcome in patients having cardiac surgery, addressing inequalities.