Dual Antiplatelet Therapy (DAPT) for Drug-Eluting Stents
For patients with drug-eluting stents (DES), DAPT should be maintained for 6-12 months, with 6 months being the standard duration for stable coronary artery disease and 12 months for acute coronary syndrome patients. 1
Primary DAPT Recommendations
Standard Duration Based on Clinical Presentation:
Stable Coronary Artery Disease with DES:
Acute Coronary Syndrome (ACS) with DES:
Stent-Specific Considerations:
- Drug-eluting stents (DES): 6 months minimum DAPT for stable CAD 1
- Bare-metal stents (BMS): 1 month minimum DAPT 1
- BioFreedom DES: May require only 1 month of DAPT in high bleeding risk patients 2
Secondary DAPT Recommendations (Duration Modifications)
Extended DAPT Duration:
- For patients with low bleeding risk but high thrombotic risk, DAPT may be extended beyond the standard duration up to 30 months (Class IIb, Level A) 1, 2
- Extended DAPT (18-48 months) decreases myocardial infarction (OR: 0.67) and stent thrombosis (OR: 0.45) but increases major hemorrhage (OR: 1.58) 1
Shortened DAPT Duration:
- For patients with high bleeding risk and stable CAD who have received a DES, 3 months of DAPT may be considered (Class IIa, Level B) 1
- Recent evidence suggests that short DAPT ≤3 months followed by single antiplatelet therapy reduces bleeding without increasing stent thrombosis risk 3
Risk Assessment for DAPT Duration
Factors Increasing Ischemic Risk:
- Advanced age
- ACS presentation
- Multiple prior MIs
- Extensive CAD
- Diabetes mellitus
- Chronic kidney disease
- Previous stent thrombosis
- Left ventricular ejection fraction <40%
- Multiple stents/vessels treated
- Complex lesions (bifurcation, long stents)
Factors Increasing Bleeding Risk:
- Advanced age
- History of bleeding
- Chronic kidney disease
- Low body weight
- Female sex
- Anemia
- Chronic oral anticoagulation
- Chronic steroid or NSAID use
Special Clinical Scenarios
Patients Requiring Surgery:
- Non-cardiac surgery should be delayed at least 1 month after stent placement regardless of stent type, and preferably 6 months in case of recent MI 1
- For patients requiring surgery during DAPT period:
Patients on Oral Anticoagulants:
- Patients requiring triple therapy (DAPT plus anticoagulation) have significantly increased bleeding risk 2
- Consider dual therapy with a P2Y12 inhibitor (preferably clopidogrel) plus an oral anticoagulant with omission of aspirin in select patients 2
Practical Considerations
- Never prematurely discontinue DAPT without consulting the patient's cardiologist, as this significantly increases stent thrombosis risk (HR=161 in some studies) 2
- Aspirin therapy should almost always be continued indefinitely in patients with CAD, even after DAPT completion 2
- Newer-generation DES have lower rates of stent thrombosis, which has influenced the trend toward shorter DAPT durations 1, 2
Common Pitfalls and Caveats
- Avoid premature DAPT discontinuation, especially within the first months after PCI, as this dramatically increases stent thrombosis risk 1, 2
- Recognize that recommendations are based on newer-generation DES, which have better safety profiles than first-generation stents 2
- Balance between thrombotic and bleeding risks must be carefully assessed for each patient 2, 1
- When determining DAPT duration, consider that extended therapy reduces ischemic events but increases bleeding complications 1
- For patients requiring temporary interruption of P2Y12 inhibitors, the 5-day window before surgery is a compromise between platelet half-life (10 days) and thrombosis risk 2