This document discusses recommendations for continuing dual antiplatelet therapy (aspirin and clopidogrel) in the perioperative period for patients who have received coronary stents and will undergo surgery. It recommends continuing this medication for 6 weeks for patients with bare metal stents and 12 months for those with drug-eluting stents. Discontinuing clopidogrel alone while maintaining aspirin may be relatively safe for drug-eluting stent patients in the short term. The risk of stent thrombosis is greatest during and immediately after surgery.

1. Dr. Ihab Suliman

2. Ingrowth of tissue may cause bare-metal stents to
become obstructed, resulting in the need for a second
procedure. Drug-eluting stents inhibit this
process, but uncovered struts may be prone to
thrombosis after discontinuation of antiplatelet
therapy.

3. Perioperative coronary stent thrombosis is a

catastrophic complicationthat can occur in
patients receiving both bare-metal and drug-
elutingstents.
Noncardiac surgery appears to increase the

risk that recently-placed stents
thrombose, especially when surgery
is performed early after stenting, and
particularly if dual antiplatelet therapy is
discontinued.

5. In patients with a bare metal coronary stent

who require surgery within 6 weeks of stent
placement, we recommend continuing aspirin
and clopidogrel in the perioperative period
(Grade 1C);
In patients with a drug-eluting coronary

stent who require surgery within 12 months
of stent placement, we recommend
continuing aspirin and clopidogrel in the
perioperative period (Grade 1C).

6. The optimal duration of clopidogrel required

to prevent late DES thrombosis is unknown.
an observational study showed reduced risk

of death or MI when clopidogrel was
continued up to 2 years after DES
implantation

7. • Continue dual antiplatelet therapy during
and after surgery
• Discontinue clopidogrel but quot;bridgequot; the
patient to surgery using a short-acting
antiplatelet agent with a glycoprotein IIb/IIIa
inhibitor or an antithrombin, and restart
clopidogrel as soon as possible after surgery
• Discontinue clopidogrel before surgery and
restart it as soon as possible after surgery

8. some clinicians quot;bridgequot; the patient to

surgery using a short-acting antiplatelet agent or
an anticoagulant. Because stent thrombosis is
primarily a platelet-mediated
phenomenon, platelet inhibitors might be a more
logical choice if such a strategy is pursued.
Furthermore, the cessation of heparin in a patient
not on aspirin or other antiplatelet agents has
been shown to cause platelet activation and a
rebound phenomenon which may actually
increase the likelihood of perioperative stent
thrombosis compared to if no heparin bridging
had been performed.

9. However, it must be emphasized that

admitting a patient to a hospital before
surgery to bridge them to surgery does not
offer complete protection because the
greatest risk of stent thrombosis is actually
during or after surgery.

10. We systematically searched Medline for

reported cases of late stent thrombosis and
very late stent thrombosis published between
January 2001 and July 2008. We restricted our
search to Academic Research Consortium–
defined definite cases. We identified 161
cases of late stent thrombosis or very late
stent thrombosis from 84 articles (

11. 79 from case reports, 61 from registries, and 21

from randomized clinical trials). Patients had a
mean age of 58.4±13.4 years, and 88% were
male. A total of 19 cases occurred in
patients who were receiving dual antiplatelet
therapy at the time of the event. If patients
stopped both antiplatelet agents
simultaneously, the median time to event was 7
days. If patients had previouslystopped a
thienopyridine with no ill effect and
subsequently stopped acetylsalicylic acid, the
median time to event was also 7 days from the
time of acetylsalicylic acid cessation.

12. If the thienopyridine was stopped but

acetylsalicylic acid was maintained, the
median time to event was 122 days. Among
the 48 patients who stopped both agents, 36
cases (75%) occurred within 10 days. Among
the 94 patients who discontinued a
thienopyridine but continued acetylsalicylic
acid, only 6 cases (6%) occurred within 10
days.

13. If acetylsalicylic acid therapy is

maintained, short-term discontinuation of a
thienopyridine may be relatively safe in
patients with drug-eluting stents.

14. The real-world use of the CYPHER stent is safer than

was shown in clinical trials.
According to the MATRIX Registry, which is

sponsored by Cordis, CYPHER's manufacturer, rates
of stent thrombosis at one year were lower than
clinical trials reported.
Most patients in the MATRIX Registry, up to 80%,

have chronic conditions such as diabetes that would
have disqualified them from clinical trials, and
therefore received stents off-label. MATRIX
investigators also found that many patients had
trouble maintaining the clopidogrel regimen and that
one-third were no longer taking the drug as
recommended at one year.

15. Found that off-label use of sirolimus-eluting

stents led to low two-year rates of
complications and thrombosis.
Of 1,521 patients, 34% had diabetes, 45% had

prior percutaneous coronary
intervention, 21% had prior coronary artery
bypass grafting, 33% had prior MI and 46%
had acute cardiac syndrome at baseline.

16. Two years after stenting, rates of cardiac

death, non-cardiac death, MI, target lesion
revascularization and target vessel
revascularization were 1.1%, 1.7%, 4%, 9% and
12%, respectively.