Improved adverse postoperative outcomes with revised American College of Cardiology/American Heart Association guidelines for patients with cardiac stents.

IMPORTANCE

In 2007, the American College of Cardiology/American Heart Association guidelines were revised for patients with cardiac stents in need of subsequent surgery to recommend delaying elective noncardiac surgery by 365 days in patients with drug-eluting stents (DESs).

OBJECTIVE

To examine the effect of the guidelines on postoperative major adverse cardiac events (MACEs) in subsequent noncardiac surgery.

DESIGN, SETTING, AND PARTICIPANTS: Patients receiving a cardiac stent between fiscal years 2005 and 2010 were identified by International Classification of Diseases, Ninth Revision diagnosis codes in the Veterans Affairs Medical SAS data sets. The Veterans Affairs Surgical Quality Improvement Program data were used to identify subsequent operations in the 2 years following stenting. The preguideline period was defined as fiscal years 2005 through 2007 and the postguideline period was defined as fiscal years 2008 through 2010. Surgery patients admitted through the emergency department or transferred from another hospital were excluded from analyses. Overall, 16,634 elective noncardiac operations were identified (8034 [48.3%] in the preguideline period; 8600 [51.7%] in the postguideline period).

MAIN OUTCOMES AND MEASURES

Composite 30-day postoperative MACEs. We used χ² tests to examine differences in bivariate frequencies and used logistic models to examine adjusted associations with 2-year postoperative MACEs.

RESULTS

The median time to surgery was 364 days (interquartile range, 184-528 days). A total of 11,026 operations (66.3%) followed DES placement, and 5608 (33.7%) followed bare metal stent placement. After the guidelines' publication, surgery timing increased following DES placement from 323 to 404 days (P < .001) and decreased following bare metal stent placement from 402 to 309 days (P < .001). In addition, postoperative MACE rates decreased from 4.2% to 3.3% (P = .002). After adjusting for cardiac risk factors and procedure characteristics, there was an overall absolute risk reduction of 0.9% for MACEs (odds ratio = 0.74; 95% CI, 0.62-0.89). On further examination of trends across time, MACE rates with DES placement began to decrease prior to the guidelines' publication from 5.5% in 2005 to 4.3% in 2006 and remained stable through 2010. In contrast, MACE rates with bare metal stent placement increased from 4.3% in 2005 to 8.0% in 2007 but decreased to 4.8% following the guidelines' publication.

CONCLUSIONS AND RELEVANCE

After the guidelines' publication, noncardiac surgery was delayed in patients with DESs but not bare metal stents. With a 26% reduction in MACEs following the guidelines, it would appear that the guidelines did improve postoperative outcomes; however, when examined over time, it becomes evident that there are many more factors influencing management of patients with cardiac stents in need of subsequent surgery.