iThoughts

Drug eluting stents (DES) were developed to reduce re-stenosis rates associated with bare stents (BMS)
Types of stent

Restenosis rate remained unacceptably high ~ 15%
Dual anti platelet therapy for 6/52 usually before cover with aspirin is sufficient.
Stent thrombosis (1%) carries huge morbidity/mortality and commonly occurs in the first month post insertion. This risk increases 30 fold if clopidogrel is stopped in this period
Late (>1/12) and very late (>12/12) thrombosis is rare
The risk of thrombosis is drastically reduced if surgery is performed > 6 weeks after insertion

Coated with rapamycin or paclitaxel which inhibit smooth muscle proliferation with lower restenosis rates (~ 2%)
Late thrombosis is a commoner problem and may carry lifelong risk if clopidogrel is stopped
The risk of thrombosis is continued up to and likely beyond 12 months

Non-cardiac surgery and most invasive procedures increase the risk of thrombosis, especially when it is performed before endothelial re-growth is established
Risk of stent thrombosis

If surgery cannot be delayed a balance must be struck between thrombosis prophylaxis and surgical bleeding
The location of the stent is important
Risks of surgical bleeding is increased with dual anti-platelet therapy (DAPT). By how much is unclear.
For high risk procedures (eg spinal/neurosurgery) the risk/benefit suggest stopping plavix
Bridging therapy

Tirofiban for 4 days pre-op (having stopped plavix the day before this) and then loaded with plavix post-op. If bleeding is a concern, the Tirofiban can be resumed and plavix reloading delayed.