Usefulness of the CHADS₂ Score for Prognostic Stratification in Patients With Coronary Artery Disease Having Coronary Artery Bypass Grafting

Current risk model for long-term survival prediction in isolated coronary artery bypass graft surgery is complicated, whereas a simple useful model is still lacking. We aim to investigate if CHADS₂ score could predict long-term outcome for patients after coronary artery bypass graft surgery. From 2000 to 2007, we identified a study cohort consisting of patients who underwent coronary bypass surgery in the Taiwan National Health Insurance Research Database. After operation, all cases were followed to track the incidence of major adverse cardiovascular events and overall mortality. During a mean 5.1-year follow-up, 638 patients experienced major cardiovascular events. Six hundred twenty-five patients passed away at the end of follow-up, whereas 204 died of cardiovascular cause. Subjects with higher CHADS₂ scores had significantly higher 10-year overall mortality and cardiovascular death, as well as the incidence of major adverse cardiovascular events. After adjustment with co-morbid condition and prescribed medications, CHADS₂ was independently associated with increased risks of all-cause mortality (hazard ratio 1.36, 95% CI 1.29 to 1.44) and cardiovascular mortality (hazard ratio 1.37, 95% CI 1.24 to 1.52). In conclusion, CHADS₂ score provides a quick and useful tool in predicting long-term outcome for patients after coronary artery bypass surgery.