The incidence and timing of noncardiac surgery after cardiac stent implantation

Background: In November 2007, national guidelines were released recommending delay of elective noncardiac surgery after cardiac revascularization with drug eluting stents (DES) for 12 months compared with 6 weeks after implantation of bare metal stents (BMS). Study Design: To determine the incidence of noncardiac surgery within 24 months after stent placement, national VA data on cardiac stent implantation were merged with data from the VA National Surgery Office and Medicare. Using chi-square tests and log-rank analyses, we measured the incidence of noncardiac surgery after BMS and DES in relation to guideline release and surgical characteristics. Results: From 2000 to 2010, 126,773 stent procedures were followed by 25,977 (20.5%) noncardiac operations within 24 months. Overall, 11.8% of the BMS surgery cohort had early surgery (less than 6 weeks) compared with 46.7% of the DES surgery cohort, which had early surgery (less than 12 months). The incidence of surgery differed significantly by stent type (BMS 24.1% vs DES 17.5%, p < 0.001) and in relation to guideline release (pre- 24.6% vs postguideline 13.1%, p < 0.001). Higher complexity operations (work relative value units) were more likely to occur in the early period for both BMS (p < 0.0001) and DES (p < 0.003). After guideline release, the incidence of surgery within 12 months decreased from 16.7% to 10.0% (p < 0.0001). Conclusions: We found evidence that guidelines recommending delaying surgery appear to be effective in decreasing the incidence of early surgery; however, early surgery is still a frequent occurrence. Additional research is needed to better define the risk of cardiac and bleeding complications in patients undergoing subsequent noncardiac surgery, as well as the optimal time for surgery and method of antiplatelet management.