What is the recommended duration of antithrombotic therapy after percutaneous coronary intervention (PCI) based on stent type, clinical presentation, and bleeding risk?

Duration of Anticoagulation After PCI

For patients undergoing PCI, anticoagulation during the procedure is mandatory but should be discontinued immediately post-procedure; the question of "duration" applies to antiplatelet therapy (DAPT), not anticoagulation, which follows distinct timelines based on clinical presentation and bleeding risk. 1

Procedural Anticoagulation (Intraprocedural Only)

• Unfractionated heparin (UFH) is recommended as routine anticoagulation during all PCI procedures. 1
• Enoxaparin should be considered as an alternative to UFH during PCI. 1
• Bivalirudin may be considered for procedural anticoagulation. 1
• All procedural anticoagulation is discontinued immediately after PCI completion—there is no extended "duration" of anticoagulation unless the patient has a separate indication (atrial fibrillation, mechanical valve, venous thromboembolism). 1

Dual Antiplatelet Therapy (DAPT) Duration: The Core Question

For Acute Coronary Syndrome (ACS) Patients

The default DAPT duration is 12 months regardless of stent type (bare-metal or drug-eluting). 1, 2, 3

• Aspirin 75–100 mg daily plus a P2Y12 inhibitor (ticagrelor 90 mg twice daily, prasugrel 10 mg daily, or clopidogrel 75 mg daily) for 12 months is mandatory. 1, 2, 3
• After 12 months, discontinue the P2Y12 inhibitor and continue aspirin indefinitely. 2, 3
• High bleeding-risk ACS patients may shorten DAPT to 6 months, then transition to aspirin monotherapy. 1, 2, 3
• Very high bleeding-risk patients require a minimum of 1 month of DAPT; stopping earlier is not supported even in life-threatening scenarios unless the bleeding source cannot be controlled. 2, 3

For Stable Coronary Artery Disease (Stable CAD)

The default DAPT duration is 6 months for drug-eluting stents and 1 month for bare-metal stents. 1, 2, 3

• Low ischemic/thrombotic risk with low bleeding risk: 3–6 months of DAPT, then aspirin monotherapy. 1
• Low ischemic/thrombotic risk with high bleeding risk: 0–3 months of DAPT (aspirin may be stopped immediately post-PCI in very high bleeding-risk cases), then single antiplatelet therapy. 1
• High ischemic/thrombotic risk with low bleeding risk: 1–6 months of DAPT, then aspirin monotherapy. 1

Extended DAPT Beyond 12 Months

In ACS patients who complete 12 months of DAPT without bleeding complications and remain at low bleeding risk, extending therapy beyond 12 months may be considered. 1, 2, 3

• Prolonged DAPT reduces myocardial infarction (6 fewer MIs per 1000 patients/year) and stent thrombosis (3 fewer events per 1000 patients/year) but increases major bleeding (5 more bleeds per 1000 patients/year). 1
• Post hoc analyses suggest weak evidence of increased mortality with prolonged DAPT, making the risk-benefit ratio unfavorable for most patients. 1
• High ischemic-risk features that may justify extension include prior MI, complex PCI (bifurcation with two stents, total stent length >60 mm), left main disease, diabetes, renal failure, and prior stent thrombosis. 1, 2

Special Population: Patients Requiring Oral Anticoagulation (OAC)

Triple therapy (aspirin + P2Y12 inhibitor + OAC) increases bleeding risk 2–3-fold and must be minimized. 1, 2, 3

Triple Therapy Duration Algorithm

• For ACS patients: Triple therapy for 1 month minimum, up to 6 months maximum based on ischemic risk. 1, 2
• For stable CAD patients: Triple therapy for 1 month, then transition to dual therapy (OAC + clopidogrel). 1, 2
• At 12 months post-PCI, discontinue clopidogrel and continue OAC alone. 1, 2

Key Modifications for OAC Patients

• Clopidogrel is the only P2Y12 inhibitor recommended; ticagrelor and prasugrel are contraindicated due to excessive bleeding risk. 1, 2, 3
• A NOAC should be preferred over warfarin based on lower bleeding rates in RE-DUAL, PIONEER, and ENTRUST-AF-PCI trials. 1
• If warfarin is used, target INR 2.0–2.5 (lower end of therapeutic range) and maintain time in therapeutic range >65%. 1
• Aspirin should be low-dose (≤100 mg daily). 1
• Proton pump inhibitors (PPIs) are mandatory to reduce gastrointestinal bleeding. 1

Bleeding Risk vs. Ischemic Risk Assessment

High Bleeding Risk Features

• History of prior bleeding, oral anticoagulant therapy, female sex, advanced age, low body weight, chronic kidney disease, diabetes, anemia, chronic steroid or NSAID use. 1

High Ischemic/Thrombotic Risk Features

• ACS presentation, multiple prior MIs, extensive coronary disease, diabetes, chronic kidney disease, left ventricular ejection fraction <40%, first-generation DES, stent undersizing/underdeployment, small stent diameter, greater stent length, bifurcation stents, in-stent restenosis. 1

Critical Pitfalls to Avoid

• Never base DAPT duration on stent type alone; clinical presentation (ACS vs. stable CAD) and bleeding risk are the primary determinants. 2, 3
• Do not use bare-metal stents to justify shorter DAPT—newer-generation drug-eluting stents are safer than BMS even with abbreviated DAPT. 2
• Never stop both aspirin and the P2Y12 inhibitor simultaneously except in uncontrolled life-threatening bleeding; stopping both dramatically increases stent thrombosis mortality (20–40%). 2, 3
• Mandatory reassessment at 12 months is required for all patients; failure to actively decide whether to continue or stop DAPT is a critical error. 2, 3
• Do not use ticagrelor or prasugrel in patients requiring oral anticoagulation—clopidogrel is the only acceptable P2Y12 inhibitor in this setting. 1, 2, 3
• Prasugrel must be discontinued immediately if a patient develops stroke or TIA. 3

P2Y12 Inhibitor Selection

• For ACS: Ticagrelor (180 mg loading, 90 mg twice daily) is preferred over clopidogrel. 1, 2, 3
• Prasugrel (60 mg loading, 10 mg daily) is acceptable in P2Y12-naïve ACS patients undergoing PCI without prior stroke/TIA. 1, 2, 3
• For stable CAD: Clopidogrel 75 mg daily is the default. 2, 3
• For patients on OAC: Clopidogrel only. 1, 2, 3

Surgical Timing Considerations

• Elective non-cardiac surgery should be delayed until at least 3 months after DES implantation (or 1 month after BMS) when postponement is acceptable. 3
• For urgent cardiac surgery, discontinue ticagrelor at least 3 days prior, clopidogrel at least 5 days prior, and prasugrel at least 7 days prior. 1
• In ACS patients undergoing CABG, resume the P2Y12 inhibitor post-operatively to complete 12 months of total DAPT from the index ACS event. 1, 3