/study / lectures / Preop Eval
DAPT Timing — BMS vs DES
TEXTPreop Eval · 9 min read
Stop the antiplatelet too early and you risk stent thrombosis; stop it too late and you bleed. ACC 2016 guidelines give the timing.
After this lesson you can
3 min read8 sections- Decide DAPT continuation/hold for non-cardiac surgery.
- Recall stent-type-specific minimum durations.
- Bridge high-risk patients.
- Manage bleeding during continued DAPT.
Why DAPT exists — stent biology
Drug-eluting stent (DES, older sirolimus/paclitaxel generation) deliberately suppresses endothelialization to prevent neointimal hyperplasia may take 12 months.
Newer-generation DES (everolimus/zotarolimus, biodegradable polymer): much faster endothelial coverage 3-6 months.
Until the stent is endothelialized, the metal struts are thrombogenic and the only thing keeping them open is dual antiplatelet therapy.
BMS vs DES — minimum durations
DES (older 1st-gen, e.g. Cypher, Taxus — mostly gone): 12 months.
Newer DES (Xience, Resolute, Synergy): 6 months optimal, 3 months acceptable if surgery clinically necessary.
Bioabsorbable scaffolds (rare): individualized — confer with cardiology.
Aspirin continued through surgery in all cases; P2Y12 inhibitor is the variable to time.
ACC 2016 update — formal recommendations
Class IIb: 3 months acceptable for newer DES if surgery benefits outweigh thrombosis risk.
Class III (harm): elective surgery within 30 days of BMS or 3 months of DES.
Always-continue aspirin perioperatively unless surgery is in a closed space (intracranial, posterior eye, TURP, spinal cord).
Premature DAPT cessation in the high-risk window has 30% mortality from stent thrombosis — this is a guideline-driven decision, not a surgeon-preference call.
Aspirin continuation — POISE-2 nuance
81 mg continues through almost all surgeries in secondary-prevention patients (post-stent, post-MI, established CAD).POISE-2 (NEJM 2014, 10,010 patients) found: no benefit and a small absolute bleeding increase from aspirin initiation in PRIMARY prevention.
Important: POISE-2 did NOT enroll stent patients in their high-risk window — don't extrapolate to them.
- intracranial surgery
- posterior chamber eye
- TURP
- spinal cord surgery
- prostate
ENT, orthopedic, abdominal, vascular, cardiac surgery: continue.
Discuss with surgeon and document.
P2Y12 inhibitor hold times
Prasugrel (Effient): 7 days — most potent, longest hold.
Ticagrelor (Brilinta): 5 days — reversible binding, shorter effective hold.
Ticlopidine (Ticlid, rare now): 14 days.
Cangrelor (IV, hospital-only): half-life <10 min — stop 1-6 hr pre-incision.
Restart oral P2Y12 postop when hemostasis confirmed — typically 24-48 hr.
Communication with prescribing cardiologist mandatory for any hold within the high-risk window.
Document the discussion + signed risk-benefit acknowledgement in chart.
Cangrelor bridging — high-risk DES patients
- IV P2Y12
- half-life <10 min
- full antiplatelet effect within minutes of starting and gone within 1 hr of stopping
0.75 mcg/kg/min IVcontinue until 1-6 hr pre-incisionresume cangrelor postop until oral P2Y12 restarted and absorbed.ICU-level monitoring; pricey.
Cardiology + anesthesia + surgery joint decision.
Urgent surgery with active P2Y12 — bleeding plan
Expectation: increased oozing throughout.
Available rescue: platelet transfusion 1 unit/10 kg + DDAVP 0.3 mcg/kg IV (mild platelet enhancement) + TXA 1 g if surgical-site fibrinolysis.
Reality: platelets transfused while P2Y12 still circulating get inactivated too — partial rescue only.
For clopidogrel + ticagrelor, full restoration requires drug clearance.
For prasugrel + ticlopidine, platelet transfusion is even less effective.
Limit hold to the surgical minimum and restart immediately postop once hemostasis confirmed.
Periprocedural decision algorithm
If yes delay.
If no step 4: assess bleeding risk of the surgery (low/intermediate/high) and consequences of stent thrombosis.
Low-bleed surgery (cataracts, dental): continue DAPT.
Intermediate (most general surgery): hold P2Y12, continue ASA.
High-bleed closed-space (intracranial): hold both, accept stent risk after acknowledgement.
Always: have a postoperative restart plan and execute it as soon as hemostasis allows.
⚠ Common pitfalls
- Stopping DAPT early in DES patients — stent thrombosis = high mortality.
- Continuing both agents for any cardiac patient — bleeding risk increases.
- Forgetting that platelets transfusion is the rescue for DAPT bleed.
- Bridging DAPT with heparin alone — no evidence of protection from stent thrombosis.
💎 Clinical pearls
- BMS: 30 day minimum DAPT; DES (newer): 3-6 month minimum.
- If urgent surgery within window: consult cardiology, ASA continuation, plan for transfusion.
- ASA alone (without ADP/P2Y12) can continue for most surgeries.
- Reversal in bleeding: platelets + DDAVP (for ASA); cangrelor bridge if available.
Recap
- BMS: 30 day minimum DAPT; DES (newer): 3-6 month minimum.
- If urgent surgery within window: consult cardiology, ASA continuation, plan for transfusion.
- ASA alone (without ADP/P2Y12) can continue for most surgeries.
- Reversal in bleeding: platelets + DDAVP (for ASA); cangrelor bridge if available.
Mark each section done to complete the module.