Non-Cardiac Surgery Soon after Cardiac Revascularization with Stents Decreasing among Veterans
BACKGROUND:
Percutaneous coronary intervention with cardiac stent implantation for treatment of coronary artery disease has increased dramatically over the past two decades. It also is estimated that approximately 5% to 15% of patients undergo a surgical procedure within two years of stent implantation, and reports of the complication of acute stent thrombosis after non-cardiac surgery have appeared, particularly when surgery occurred early after drug eluting stent (DES) implantation. In November 2007, American College of Cardiology/American Heart Association (ACC/AHA) guidelines were released that recommended delay of elective non-cardiac surgery for 12 months after cardiac revascularization with DES, compared with six weeks for bare metal stents (BMS). Using VA and Medicare data, this retrospective cohort study examined the incidence of non-cardiac surgery within 24 months after stent placement among 102,678 Veterans who received cardiac stents between 10/99 and 9/10 within the VA healthcare system.
FINDINGS:
- From 2000 to 2010, 126,773 stent procedures among Veterans in this study were followed by 25,977 (21%) non-cardiac surgeries within 24 months. Overall, 12% of Veterans in the BMS cohort had early surgery (less than 6 weeks) compared with 47% of Veterans in the DES cohort who had early surgery (less than 12 months).
- Rates of non-cardiac surgery within the first year after a DES placement have steadily declined (15% to 8%), suggesting that the ACC/AHA guidelines are being adopted into practice across the VA healthcare system.
- The authors note that nearly half of operations after a DES, including major procedures, were performed within the first 12 months. Thus, many Veterans are still undergoing high-risk non-cardiac procedures during the high-risk time period after cardiac stent placement. They suggest further research is needed to better define the "safe" period — and to determine whether adherence to recommendations regarding continued anti-platelet therapy among those undergoing early surgery mitigates the risk of early surgery.
LIMITATIONS:
- Medicare claims data on Veterans are available only through 2008, therefore, investigators could not fully assess the effect of guidelines on rates of surgeries conducted outside VA.
- Information on the type of stent used and subsequent surgeries was derived primarily from administrative data, so findings may be subject to misclassification bias.
AUTHOR/FUNDING INFORMATION:
This study was funded by HSR&D, and Dr. Maddox was supported by an HSR&D Career Development Award. Drs. Hawn, Graham, Richman, and Altom are part of HSR&D's Center for Surgical, Medical Acute care Research and Transitions, Birmingham, AL.
Hawn M, Graham L, Richman J, Itani K, Plomondon M, Altom L, Henderson W, Bryson C, and Maddox T. The Incidence and Timing of Non-Cardiac Surgery after Cardiac Stent Implantation. Journal of the American College of Surgeons February 15, 2012;e-pub ahead of print.
