II. Management: Guidelines
-
Aspirin or P2Y12 Inhibitor (e.g. Clopidogrel)
- Aspirin 81 mg dose appears sufficient in most cases
- Post-CABG, Aspirin 325 mg daily may be used for the first year
- Initial dosing in Myocardial Infarction is 324 mg
- Cerebrovascular Disease
- See Antiplatelet Therapy in CVA and TIA
- Initial Transient Ischemic Attack (TIA)
- Initial Ischemic Cerebrovascular Accident (CVA)
- Cardiovascular Disease
- Aspirin 81 mg dose appears sufficient in most cases
-
Aspirin 81 mg and P2Y12 Inhibitor (Clopidogrel 75 mg, Ticagrelor 90 mg twice daily or Prasugrel 10 mg daily)
- See Antiplatelet Therapy in CVA and TIA
- ST Segment elevation Acute Coronary Syndrome
- Recurrent Acute Coronary Syndrome
- Post-coronary stenting (with P2Y12 Inhibitor duration based on type of stent)
- See below for duration, and P2Y12 Inhibitor selection
- Established cardiovascular disease (or high risk) without indication for coronary stenting
- Dual therapy lowers MI and CVA risk but does not lower mortality and does increase bleeding risk
- Indications and duration per local expert opinion (consult cardiology)
- Squizzato (2017) Cochrane Database Syst Rev (12):CD005158 +PMID:29240976 [PubMed]
-
Aspirin and Extended release Dipyridamole
- See Antiplatelet Therapy in CVA and TIA
- Recurrent Transient Ischemic Attack (TIA)
- Recurrent Ischemic Cerebrovascular Accident (CVA)
-
Aspirin, P2Y12 Inhibitor (e.g. Clopidogrel) and Anticoagulant (Warfarin or DOAC)
- Triple antithrombotic therapy may at times be indicated
- Baseline Atrial Fibrillation or Mechanical Heart Valve with recent coronary stent placement
- Avoid triple antithrombotic therapy if at all possible (high bleeding risk)
- Serious bleeding in 2% within the first month and 12% in the first year
- In some cases Direct Oral Anticoagulants (DOACs, esp. Eliquis) are used in place of Warfarin
- In stable heart disease, triple therapy for 3 months after bare stent and 6 months after DES
- Then Anticoagulant and Clopidogrel for up to 12 months total
- Then Aspirin or Clopidogrel longterm
- (2017) Presc Lett 24(4): 22
- Often Aspirin may be discontinued while on P2Y12 Inhibitor (e.g. Clopidogrel) and Anticoagulant (Warfarin or DOAC)
- Consider triple therapy with Aspirin for first month after stenting, then stop Aspirin
- Dual therapy has half of the bleeding risk of triple therapy without significant increased CAD event risk
- Consider in those after elective coronary stent placement or multiple bleeding risks
- Aspirin may then be restarted when Clopidogrel is discontinued
- (2019) Presc Lett 26(5)
- Dewilde (2013) Lancet 381(9872): 1107-15 [PubMed]
- Triple antithrombotic therapy may at times be indicated
III. Protocol: Selection of P2Y12 Inhibitor (Platelet ADP Receptor Antagonist)
-
Clopidogrel 75 mg orally daily
- Clopidogrel was the first P2Y12 Inhibitor
- Historically used most often (and is only $5/month in 2025)
- Clopidogrel has lower efficacy in first week (slower onset) after coronary stenting than orher P2Y12 Inhibitors
- However, similar outcomes to other P2Y12 Inhibitors after first week
- Consider switching to Clopidogrel after the first month on other P2Y12 Inhibitor
- Rezaei (2017) Int J Cardiol 235:61-66 [PubMed]
- Sibbing (2017) Lancet 390(10104):1747-57 [PubMed]
-
Ticagrelor 90 mg twice daily
- Preferred for faster onset after coronary stenting and fewer adverse cardiovascular events
- Most expensive P2Y12 Inhibitor ($460/month in 2025)
-
Prasugrel 10 mg daily
- As with Ticagrelor, faster onset and higher efficacy than Clopidogrel
- Higher bleeding risk than other P2Y12 Inhibitors (esp. age >75 years, weight <60 kg)
- References
- (2025) Presc Lett 32(4): 21
IV. Protocol: Durations of post-coronary stenting Dual Antiplatelet Therapy (e.g. Aspirin 81 AND Clopidogrel)
- Duration: 1 month of Dual Antiplatelet Therapy (DAPT)
- Bare metal stent
- Duration: 3 months of Dual Antiplatelet Therapy (DAPT), followed by 9 months of Clopidogrel (or Ticagrelor) alone, then Aspirin alone
- HIgh risk of bleeding (e.g. Gastrointestinal Bleeding, Intracranial Bleeding, advanced age) AND
- Stable Ischemic Heart Disease after Drug-eluting Stent
- Duration: 6 months of Dual Antiplatelet Therapy (DAPT), then Aspirin daily
- Standard duration of DAPT for Stable Ischemic Heart Disease after Drug-eluting Stent (as of 2016)
- Follow with 6 months of Clopidogrel (or Ticagrelor) alone, then Aspirin alone
- Duration: 12 months of Dual Antiplatelet Therapy (DAPT), then Aspirin daily
- Acute Coronary Syndrome event (regardless of stenting)
- Duration: 18 months of Dual Antiplatelet Therapy (DAPT), then Aspirin daily
- DAPT Score (Dual-Antiplatelet Therapy Decision Rule) of 2 or greater
- References
- (2022) Presc Lett 29(2): 12
- Levine (2016) J Am Coll Cardiol +PMID:27036918 [PubMed]
- Yeh (2016) JAMA 315(16):1735-9 [PubMed]
V. Protocol: Post-Myocardial Infarction
- Aspirin 81 mg orally daily indefinitely
-
P2Y12 Inhibitor (e.g. Clopidogrel) added to Aspirin routinely following ST Elevation MI
- P2Y12 Inhibitor options (Ticagrelor, Prasugrel, Clopidogrel)
- Duration following ST Elevation MI (typically 12 months)
- See Platelet ADP Receptor Antagonist (e.g. Clopidogrel)
- Continue for at least 14 days and consider one year of therapy in all post-STEMI cases
- Stenting-related durations
- Bare metal stents require minimum of 1 month of P2Y12 Inhibitor (e.g. Clopidogrel)
- Drug-eluting Stents require minimum of >6-12 months (depending on stent-type)
- See Angioplasty
- Possible benefit of Ticagrelor, Prasugrel over Clopidogrel, but at higher bleeding risk and 30x cost
- However, Clopidogrel may offer similar efficacy after the first week post-stenting
VI. Precautions: Perioperative Stent Implications
- See Angioplasty
- Balloon Angioplasty
- Time since surgery <14 days: Delay non-urgent or elective surgery
- Time since surgery >14 days: Proceed to surgery with Aspirin
-
Bare-Metal Stent
- Time since surgery <30-45 days: Delay non-urgent or elective surgery
- Time since surgery >45-90 days: Proceed to surgery with Aspirin
-
Drug-eluting Stent
- Time since surgery <365 days: Delay non-urgent or elective surgery
- Time since surgery >365 days: Proceed to surgery with Aspirin
- Minimum dual antiplatelet time for stents
- Dual Antiplatelet Therapy should be continued for one year with all drug eluting stents
- Deviation from the one year minimum is for serious extenuating circumstances
- All deviations from the one year minimum should be discussed with cardiology
- Balloon Angioplasty: >2 weeks
- Bare metal stents: >1 month
- Sirolimus (Rapamune) eluting stents: >3 months
- All other Drug-eluting Stents: >6-12 months
- Dual Antiplatelet Therapy should be continued for one year with all drug eluting stents
VII. Management: Gastrointestinal Prophylaxis
-
Proton Pump Inhibitors are often used for Peptic Ulcer prevention while on combined anti-Platelet agents
- Ranitidine has been used more commonly for GI prophylaxis
- Potential Cytochrome P450 2C19 Drug Interaction with Proton Pump Inhibitors
-
Cytochrome P450 2C19 Drug Interaction with Proton Pump Inhibitors
- Potential to predispose to more post-stenting events
- Cogent study (see Bhatt below) left open that this interaction may be important
- Studies have not observed an increase in number of cardiovascular events
VIII. Protocol: Perioperative P2Y12 Inhibitor (e.g. Clopidogrel)
- Precautions
- See perioperative stenting implications above
- Mortality doubles in Acute Coronary Syndrome patients in first 90 days after stopping Clopidogrel
- Consider tapering off by taking every other day for 2-3 weeks
- Conitinue Aspirin 162 after stopping Clopidogrel
- Ho (2008) JAMA 299(5):532-9 [PubMed]
- Timing of stopping Clopidogrel (if no contraindications)
- Stop 7 days before surgery (delay surgery if too soon after cardiovascular event)
IX. Protocol: Perioperative Aspirin
- Precautions
- Protocol
- Consult with surgeon regarding whether Aspirin may be continued
- Low dose Aspirin can be continued in the perioperative period for most surgeries
- Surgical bleeding risk increases with Aspirin by 20%
- However, no increase in severe bleeding for most surgeries (except intracranial surgery or Prostatectomy)
- References