乌鸦传媒

Noncardiac surgery soon after getting a stent carries higher risks for patients who were sickest when they received their stent -- those with myocardial infarction (MI) as the indication rather than a less serious blockage, a study showed.

The postoperative major adverse cardiovascular event (MACE) rate was compared with 2.7% among those stented for unstable angina and 2.6% for those with indications other than acute coronary syndrome (ACS, P<0.001), , of California's Stanford University, and colleagues found.

When surgery occurred within 3 months of stenting, the MI indication group was 5.25-fold more likely to have a major cardiovascular event as a complication than those who had received a stent for non-ACS reasons, after adjustment for other factors.

"This risk decreased over time, although it remained significantly higher at 12 to 24 months from percutaneous coronary intervention (OR 1.95; 95% CI 1.58-2.40)," the researchers reported online Dec. 30 in JAMA Surgery.

"Delaying surgery up to 6 months following percutaneous coronary intervention may be most important for patients with stents placed for MI irrespective of stent type," they concluded.

Unstable angina and other non-ACS reasons for stenting history had a similar impact on MACE risk when surgery was performed within 3 months or 12 to 24 months later. Stent type was not significantly associated with MACE regardless of indication.

The group had previously shown that history of MI in the prior 6 months was one of the strongest predictors of MACE after noncardiac surgery in stented patients, with the timing of that surgery being a weaker predictor.

The new analysis by indication for stenting used the same retrospective data from 26,661 patients (median age 68, 98.4% male, 88.1% white) who underwent 41,815 surgical procedures within 24 months following coronary stent placement at VA hospitals from 2000 through 2010.

"While the literature is far from clear as to the time needed to be receiving dual antiplatelet therapy following drug-eluting stent placement, recent guidelines have suggested that treating patients with drug-eluting stents with dual antiplatelet therapy for a full 12 months is best prior to proceeding with elective noncardiac surgery," , of the University of Virginia, in Charlottesville, noted in an accompanying editorial.

"Based on the present study, it is clear that when preparing a patient for surgery (especially respiratory or vascular surgery), obtaining a history of the indication for coronary stent placement is critical and delaying nonemergent surgery on those who had an MI as their indication for coronary stenting for a full 6 months is likely prudent," he concluded.