Outcomes of Coronary Artery Bypass Grafting in Patients With Previous Mediastinal Radiation

Studies have shown that patients with radiation therapy-associated coronary artery disease tend to have worse outcomes with percutaneous revascularization. Previous irradiation has been linked with future internal mammary artery graft disease. Studies investigating the outcomes of coronary artery bypass surgery (CABG) among patients with previous radiation are limited. The Nationwide Readmission Database for the years 2016 to 2019 was queried for hospitalizations with CABG and history of mediastinal radiation. Complex samples multivariable logistic and linear regression models were used to determine the association between the history of mediastinal radiation and in-hospital mortality, 90 days all-cause unplanned readmission rates, and acute coronary syndrome readmission rates. A total of 533,702 hospitalizations (2,070 in the irradiation history group and 531,632 in the control group) were included in this analysis. Patients with radiation therapy history were less likely to have traditional coronary artery disease risk factors and more likely to have associated valvular disease. Patients with a history of irradiation had similar in-hospital mortality and 90-day readmission risk at the expense of higher hospitalizations costs (β coefficient: $2,764; p = 0.005). They had a higher likelihood of readmission with acute coronary syndrome within 90 days (adjusted odds ratio 1.67, p = 0.02). In a conclusion, a history of mediastinal irradiation is not associated with increased rates of short-term mortality or increased all-cause readmission risk after CABG. However, it may be associated with increased acute coronary syndrome readmission rates.