What is the recommended duration of Dual Antiplatelet Therapy (DAPT) for a patient with a 2.5 mm x 22 mm stent in the proximal to mid Left Anterior Descending (LAD) artery?

DAPT Duration for Proximal-Mid LAD Stenting

For a 2.5 mm x 22 mm stent in the proximal to mid LAD, you should prescribe dual antiplatelet therapy (DAPT) for a minimum of 6 months if this was placed for stable coronary artery disease, or 12 months if placed for acute coronary syndrome (ACS), with strong consideration for extending beyond 12 months given the high-risk location and stent characteristics. 1, 2

Clinical Context Determines Baseline Duration

For Stable Coronary Artery Disease

• The minimum recommended DAPT duration is 6 months for drug-eluting stents, regardless of stent type 1
• This represents a decrease from the previous 12-month recommendation based on newer-generation DES having lower thrombosis rates 1
• The standard regimen consists of aspirin 81 mg daily (range 75-100 mg) plus a P2Y12 inhibitor 1, 2

For Acute Coronary Syndrome

• DAPT must be continued for at least 12 months after stent placement in any ACS presentation (NSTEMI or STEMI) 1, 3
• For ACS patients, ticagrelor 90 mg twice daily or prasugrel 10 mg daily are preferred over clopidogrel 75 mg daily 1, 3
• Prasugrel should not be used if the patient has prior stroke or TIA 1

High-Risk Features Favoring Extended DAPT

Proximal LAD Location is Critical

• Proximal LAD stents are considered high-risk due to the large territory of myocardium at risk if stent thrombosis occurs 2, 4
• The proximal LAD supplies a substantial portion of the left ventricle, making thrombosis potentially catastrophic with mortality rates of 20-45% 2
• Stent thrombosis results in death or myocardial infarction in 64.4% of cases 2

Small Stent Diameter Increases Risk

• A 2.5 mm diameter stent is relatively small and may indicate a smaller vessel caliber, which is associated with higher thrombosis risk 1
• The 22 mm length is moderate but any stent length contributes to thrombotic risk 1

Consider Extended DAPT Beyond 12 Months If:

• The patient has tolerated DAPT without bleeding complications 1, 3
• The patient is not at high bleeding risk (PRECISE-DAPT score <25) 1, 5
• The patient has high ischemic risk features (DAPT score ≥2) 1, 2
• Extended DAPT (18-36 months) reduces stent thrombosis (OR 0.45) and MI (OR 0.67) but increases major bleeding (OR 1.58) 3
• The absolute benefit is approximately 3 fewer stent thromboses and 6 fewer MIs per 1000 patients per year, versus 5 more major bleeds 3

Risk Stratification Tools

Assess Bleeding Risk with PRECISE-DAPT Score

• Calculate the PRECISE-DAPT score using: age, creatinine clearance, hemoglobin, white blood cell count, and prior spontaneous bleeding 1, 5
• A score ≥25 indicates high bleeding risk and supports shorter DAPT duration (3-6 months) 1, 2
• A score <25 indicates the patient can tolerate standard or extended DAPT 1, 5
• The score can be calculated at www.precisedaptscore.com 1

Assess Ischemic Risk

• High ischemic risk features include: ACS presentation, diabetes, prior MI, multivessel disease, chronic kidney disease, or complex PCI (multiple/overlapping stents) 1, 2
• Patients with multiple overlapping stents in the LAD require prolonged or even lifelong DAPT if tolerated 1, 2

Specific Regimen Recommendations

Standard DAPT Regimen

• Aspirin 81 mg daily (range 75-100 mg) is the recommended dose for long-term therapy 1, 2
• Lower aspirin doses (75-162 mg) are preferred over higher doses due to fewer bleeding complications 2

P2Y12 Inhibitor Selection

• For stable CAD: Clopidogrel 75 mg daily is appropriate 2, 6
• For ACS: Ticagrelor 90 mg twice daily is preferred over clopidogrel 1, 3
• For ACS without stroke/TIA history and not at high bleeding risk: Prasugrel 10 mg daily may be chosen over clopidogrel 1, 3

Critical Management Considerations

Never Stop DAPT Without Cardiology Consultation

• Patients with coronary stents should not stop DAPT without consulting their cardiologist 2, 4
• Premature discontinuation, particularly in the first 6-12 months, is associated with catastrophic stent thrombosis 1, 4
• If elective noncardiac surgery is needed, it should be delayed at least 1 month after bare-metal stent and optimally 6 months after drug-eluting stent implantation 1

If High Bleeding Risk Develops

• Discontinuation of P2Y12 inhibitor after 6 months may be reasonable if high bleeding risk develops (e.g., need for oral anticoagulation, major surgery planned, significant overt bleeding) 1, 3
• Continue aspirin indefinitely even if P2Y12 inhibitor is stopped 1, 2
• Consider proton pump inhibitor for gastric protection in all patients on DAPT 1

Alternative Strategies After Initial DAPT

• For selected high ischemic risk patients without high bleeding risk, consider ticagrelor 90 mg twice daily monotherapy after 3 months of DAPT 2
• For patients with prior MI and high-risk characteristics, ticagrelor 60 mg twice daily plus aspirin may reduce ischemic events 2

Common Pitfalls to Avoid

• Do not assume all LAD stents carry equal risk—proximal location significantly increases the stakes 2, 4
• Do not use a one-size-fits-all approach—bleeding and ischemic risk must be individually assessed 1, 5
• Do not stop DAPT for diagnostic procedures like EGD—the bleeding risk is minimal compared to stent thrombosis risk 4
• Do not forget that very late stent thrombosis can occur even with newer-generation DES, particularly after DAPT discontinuation 1
• Do not use prasugrel in patients with prior stroke or TIA 1