Repeat coronary revascularization after coronary artery bypass surgery in older adults: the Society of Thoracic Surgeons' national experience, 1991-2007.

BACKGROUND: A major advantage of coronary artery bypass graft surgery (CABG) relative to percutaneous coronary intervention is its durability, yet there is a paucity of information on rates and predictors of repeat coronary revascularization after CABG in the modern era. METHODS AND
RESULTS: We included patients ≥65 years from the Society of Thoracic Surgeons' National Adult Cardiac Surgery Database who were undergoing first-time isolated CABG from 1991 to 2007 (n=723 134, median age 73 years). After linking to Medicare claims data, long-term outcomes of CABG (up to 18 years after surgery) were examined by use of cumulative incidence curves. Multivariable Cox proportional hazard analysis was used to identify factors associated with 1- and 5-year repeat revascularization trends and variability. We found that the overall 18-year survival rate was 20%. Cumulative incidences of any repeat revascularization (percutaneous coronary intervention or CABG, yet most often percutaneous coronary intervention) were 2%, 7%, 13%, and 16% at 1, 5, 10, and 18 years after surgery, respectively. The rates of repeat CABG procedures were quite low for all time points (0.1%, 0.6%, 1.3%, and 1.7%, respectively). Female sex, disease severity represented by a history of percutaneous coronary intervention, preoperative dialysis, and partial revascularization were strongly associated with a higher revascularization rate, whereas advanced age, left main disease, and smoking were associated with a lower rate. There was approximately a 2-fold variation in repeat revascularization rates across centers at 1 year (interquartile range 1.7-3.6%) and 5 years (interquartile range 6.7-12.0%).
CONCLUSIONS: Repeat revascularization is performed infrequently among older patients who undergo CABG; however, these rates vary substantially by patient subgroups and among providers.