Guidelines recommend delaying noncardiac surgery in patients after coronary stent
procedures for 1 year after drug-eluting stents (DES) and for 6 weeks after bare metal
stents (BMS). The evidence underlying these recommendations is limited and conflicting.
To determine risk factors for adverse cardiac events in patients undergoing noncardiac
surgery following coronary stent implantation.
A national, retrospective cohort study of 41,989 Veterans Affairs (VA) and non-VA
operations occurring in the 24 months after a coronary stent implantation between
2000 and 2010. Nonlinear generalized additive models examined the association between
timing of surgery and stent type with major adverse cardiac events (MACE) adjusting
for patient, surgery, and cardiac risk factors. A nested case-control study assessed
the association between perioperative antiplatelet cessation and MACE.
A composite 30-day MACE rate of all-cause mortality, myocardial infarction, and cardiac
revascularization.
Within 24 months of 124,844 coronary stent implantations (47.6% DES, 52.4% BMS), 28,029
patients (22.5%; 95% CI, 22.2%-22.7%) underwent noncardiac operations resulting in
1980 MACE (4.7%; 95% CI, 4.5%-4.9%). Time between stent and surgery was associated
with MACE (<6 weeks, 11.6%; 6 weeks to <6 months, 6.4%; 6-12 months, 4.2%; >12-24
months, 3.5%; P < .001). MACE rate by stent type was 5.1% for BMS and 4.3% for DES
(P < .001). After adjustment, the 3 factors most strongly associated with MACE were
nonelective surgical admission (adjusted odds ratio [AOR], 4.77; 95% CI, 4.07-5.59),
history of myocardial infarction in the 6 months preceding surgery (AOR, 2.63; 95%
CI, 2.32-2.98), and revised cardiac risk index greater than 2 (AOR, 2.13; 95% CI,
1.85-2.44). Of the 12 variables in the model, timing of surgery ranked fifth in explanatory
importance measured by partial effects analysis. Stent type ranked last, and DES was
not significantly associated with MACE (AOR, 0.91; 95% CI, 0.83-1.01). After both
BMS and DES placement, the risk of MACE was stable at 6 months. A case-control analysis
of 284 matched pairs found no association between antiplatelet cessation and MACE
(OR, 0.86; 95% CI, 0.57-1.29).
Among patients undergoing noncardiac surgery within 2 years of coronary stent placement,
MACE were associated with emergency surgery and advanced cardiac disease but not stent
type or timing of surgery beyond 6 months after stent implantation. Guideline emphasis
on stent type and surgical timing for both DES and BMS should be reevaluated.