What is the recommended duration of dual antiplatelet therapy (DAPT) post stent placement?

Duration of Dual Antiplatelet Therapy Post Stent Placement

For acute coronary syndrome (ACS) patients, continue DAPT for a minimum of 12 months; for stable coronary artery disease patients with drug-eluting stents, the minimum duration is 6 months, with 3 months acceptable in high bleeding risk patients. 1, 2

Standard DAPT Duration by Clinical Presentation

Acute Coronary Syndrome (ACS)

• DAPT must be continued for at least 12 months after stent implantation, regardless of stent type (bare-metal or drug-eluting). 1, 2
• Both ACC/AHA (2016) and ESC (2017) guidelines align on this 12-month minimum for ACS patients. 3
• Use ticagrelor preferentially over clopidogrel for maintenance therapy (ACC Class IIa recommendation, ESC Class I recommendation). 3, 1
• Prasugrel is reasonable over clopidogrel in patients without high bleeding risk and no history of stroke or TIA. 1, 2

Stable Coronary Artery Disease

• The default DAPT duration is 6 months for drug-eluting stents. 3, 1
• ACC/AHA guidelines recommend 6 months after drug-eluting stent and 1 month after bare-metal stent. 3
• ESC guidelines recommend 6 months regardless of stent type. 3
• For high bleeding risk patients, 3 months of DAPT may be considered (ESC Class IIa, ACC/AHA Class IIb). 3, 2, 4

Aspirin Dosing Throughout DAPT

• Use low-dose aspirin 81 mg daily (range 75-100 mg) when combined with a P2Y12 inhibitor to minimize bleeding risk while maintaining antiplatelet efficacy. 1, 2

Extended DAPT Beyond 12 Months

When to Consider Extension

• For ACS patients who have tolerated DAPT without bleeding complications and are not at high bleeding risk, continuation beyond 12 months may be reasonable (Class IIb recommendation). 3, 1
• High thrombotic risk features favoring extension include: complex left main stenting, two-stent bifurcation technique, suboptimal stenting result, prior stent thrombosis, or multiple stents. 4

Risk-Benefit Profile of Extended DAPT

• Extended DAPT reduces stent thrombosis (OR 0.45; 95% CI: 0.24-0.74) and myocardial infarction (OR 0.67; 95% CI: 0.47-0.95). 1, 4
• However, extended DAPT increases major bleeding (OR 1.58; 95% CI: 1.20-2.09). 1, 4
• The absolute risk-benefit translates to 3 fewer stent thromboses and 6 fewer MIs but 5 more major bleeds per 1,000 patients treated per year. 1

Early Discontinuation Considerations

High Bleeding Risk Patients

• Discontinuation at 6 months may be reasonable in ACS patients who develop high bleeding risk, are at high risk of severe bleeding complications, or develop significant overt bleeding. 2
• For stable CAD patients with high bleeding risk, discontinuation at 3 months is acceptable. 2, 4
• Formal bleeding risk stratification should be performed at 3 months using validated criteria. 4

Noncardiac Surgery Timing

• ACC/AHA: Surgery must be delayed 1 month after bare-metal stents and 6 months after drug-eluting stents (Class I). 3
• ESC: Surgery should occur no sooner than 1 month irrespective of stent type (Class IIa), and no sooner than 6 months in case of recent MI or other high ischemic risk features (Class IIb). 3

P2Y12 Inhibitor Selection and Management

Preferred Agents in ACS

• Ticagrelor or prasugrel are preferred over clopidogrel in ACS patients (ACC Class IIa, ESC Class I). 3, 1
• Both prasugrel and ticagrelor show similar efficacy and safety in head-to-head comparisons. 3

Critical Contraindications

• Never use prasugrel in patients with prior stroke or TIA due to increased bleeding risk. 2
• Avoid prasugrel in patients at high bleeding risk. 1, 2

Perioperative Management for CABG

• Discontinue P2Y12 inhibitors before CABG: at least 3 days for ticagrelor, 5 days for clopidogrel, and 7 days for prasugrel. 2
• Resume P2Y12 inhibitor therapy after surgery to complete 12 months of DAPT in ACS patients. 2

Decision Algorithm at Key Time Points

At 3 Months Post-Stenting

• High bleeding risk patients with stable CAD who remain event-free can discontinue DAPT. 4
• ACS patients must continue to 12 months minimum regardless of bleeding risk, unless life-threatening bleeding occurs. 2, 4
• Patients with high thrombotic risk features (complex stenting, prior stent thrombosis, multiple stents) should continue DAPT beyond 3 months. 4

At 12 Months Post-Stenting

• Reassess both bleeding and ischemic risks. 2
• Low bleeding risk ACS patients with high thrombotic risk can consider extended DAPT. 1, 4
• Stable CAD patients without high thrombotic risk should discontinue DAPT. 4

Common Pitfalls to Avoid

• Do not prematurely discontinue DAPT within the first 12 months after ACS without compelling bleeding-related reasons. 2
• Avoid failing to reassess both bleeding and ischemic risks at regular intervals, particularly at 3 and 12 months. 2
• Do not continue DAPT beyond 12 months without formal risk stratification using validated scores (DAPT score, PRECISE-DAPT score). 3

Proton Pump Inhibitor Co-Administration

• ESC recommends proton pump inhibitors as Class I for all patients on DAPT. 3
• ACC/AHA recommends Class I for patients with history of gastrointestinal bleeding or those at increased risk. 3