II. Precautions
-
Aspirin is lifelong therapy for known cardiovascular disease (secondary prevention)
- Should not be interrupted for surgery following stroke, Acute Coronary Syndrome, or coronary revascularization
- This is regardless of time since vascular event or procedure
- See risks below regarding stopping Aspirin in the perioperative period
-
Clopidogrel (Plavix) in combination with Aspirin
- Should be continued at least until endothelialization of the stent or lesion can reasonably be expected
- For Drug-eluting Stents this duration is for a minimum of 1 year
- May extend 2-3 years especially in high risk patients (see below)
III. Physiology: Antiplatelet agents and bleeding risk
IV. Physiology: Stent and coronary lesion endothelialization
- Stents and coronary lesions act as unstable Plaque until fully covered by a cellular layer
- Bare metal stents are completely covered by smooth muscle within 6 weeks and by endothelium within 3 months
- Drug eluting stents require 1-3 years for endothelialization
- Stent thrombosis is a catastrophic event (up to 45% mortality)
V. Physiology: Antiplatelet agent cessation and thrombosis risk
- Aspirin cessation: 3.1 Odds Ratio of cardiac complication (peak at 10 days)
-
Aspirin cessation after coronary stent: 90 Odds Ratio
- Even 2 years after Drug-eluting Stent placement, Aspirin cessation may result in stent stenosis
- Clopidogrel cessation after drug eluting stent: Up to 57 Odds Ratio in first 18 months
- Risk of stent closure increases in the perioperative period due to increased platelet aggregation activity
VI. Evaluation: Surgical Bleeding Risk
- Low surgical bleeding risk (transfusion not required)
- Minor otolaryngology surgery
- Minor orthopedic surgery
- Endoscopy without biopsy
- Anterior chamber eye surgery
- Dentistry
- Intermediate surgical bleeding risk (transfusion may be required)
- Visceral surgery
- Vascular surgery
- Major otolaryngology surgery
- Major orthopedic surgery
- Endoscopy with biopsy
- High surgical bleeding risk (transfusion required)
- Cardiac surgery
- Surgery with massive bleeding (e.g. transurethral Prostatectomy)
- Surgery in a closed space
- Intracranial surgery
- Major spinal surgery
- Bone Intramedullary canal procedures
- Posterior eye chamber
VII. Evaluation: Cardiac Risk for perioperative events in known coronary disease
- Low Cardiac Risk
- Bare metal stents, Angioplasty, or CABG >3 months prior
- Acute Coronary Syndrome >6 months prior
- Drug-eluting Stent >12 months prior
- Intermediate Cardiac Risk
- Bare metal stents, Angioplasty, or CABG 6 weeks to 3 months prior
- Acute Coronary Syndrome 6 weeks to 6 months prior
- High Risk Drug-eluting Stent >12 months prior
- Stent in dominant, proximal, ostial or bifurcated position or
- High risk patient with advanced age, Diabetes Mellitus, low ejection fraction or Renal Failure
- High Cardiac Risk
- Bare metal stents, Angioplasty, or CABG, Acute Coronary Syndrome <6 weeks prior (<3 months if complications)
- Drug-eluting Stent <12 months prior (longer if high risk drug eluting stent)
VIII. Protocol: ACC/AHA Guidelines 2016
- No known cardiovascular disease (primary prevention)
- If significant risk of cardiovascular event (Revised Cardiac Risk Index)
- Follow guidelines for secondary prevention as below
- Stop Aspirin 7-10 days prior to surgery
- Restarting Aspirin
- If significant risk of cardiovascular event (Revised Cardiac Risk Index)
- Known cardiovascular disease (secondary prevention)
- Aspirin
- Continue without stopping through perioperative period
- Only stop Aspirin if high risk of bleeding (see above)
- Platelet ADP Receptor Antagonist (e.g. Clopidogrel, dual Antiplatelet Therapy)
- Continue Aspirin perioperatively if possible while off Platelet ADP Receptor Antagonist
- Elective surgery
- Postpone surgery for 30 days after bare metal stent, 6 months after Drug-eluting Stent
- Postpone surgery for 1 year after Acute Coronary Syndrome
- Hold Platelet ADP Receptor Antagonist perioperatively
- Important surgery to be done as soon as possible (risk of delay)
- Postpone surgery for >3 months after Drug-eluting Stent (or use dual antiplatelets periop)
- Postpone surgery for 1 year after Acute Coronary Syndrome (or use dual antiplatelets periop)
- Hold Platelet ADP Receptor Antagonist perioperatively
- Urgent or emergent surgery
- Continue dual antiplatelet agents unless major bleeding risk (e.g. active bleeding, intracranial surgery)
- Aspirin
- References
