DAPT Score

Why use it

Individualizes DAPT duration decisions using validated risk-benefit analysis. Prevents both premature discontinuation (increasing MI/stent thrombosis risk) and unnecessarily prolonged DAPT (increasing bleeding risk). ACC/AHA 2016 guidelines endorse DAPT score for guiding DAPT duration decisions after PCI.

About

The DAPT (Dual Antiplatelet Therapy) score identifies patients who will benefit from or be harmed by prolonged dual antiplatelet therapy (beyond 12 months) after percutaneous coronary intervention (PCI). It was derived from the landmark DAPT Trial (n = 11,648 patients), which randomized patients to continue or discontinue thienopyridine therapy 12 months after coronary stent placement. A DAPT score ≥ 2 indicates net clinical benefit from extended DAPT (reduced ischemic events outweigh increased bleeding risk), while a score < 2 indicates net harm (bleeding risk predominates). The score incorporates both ischemic and bleeding risk variables to provide a net clinical benefit estimate.

When to use

• 12 months after coronary stent placement, when deciding whether to continue or discontinue thienopyridine (clopidogrel, prasugrel, or ticagrelor)
• Risk-benefit discussion with patients about extended DAPT
• Planning DAPT duration at time of PCI for patients expected to complete 12 months of therapy

Formula

Pearls & pitfalls

• DAPT score ≥ 2 corresponds to ~70% relative reduction in MI/stent thrombosis with 38% relative increase in moderate-to-severe bleeding.
• Score < 2: Prolonging DAPT increases bleeding WITHOUT significant ischemic benefit — stop thienopyridine at 12 months.
• Aspirin should always be continued indefinitely (unless contraindicated) regardless of DAPT score.
• The score was derived in patients completing 12 months of DAPT without major events — confirm eligibility before applying.
• Prasugrel use (vs. clopidogrel) is a negative factor (no additional benefit from prolonging prasugrel beyond 12 months in the DAPT trial).
• ACS (vs. stable presentation) is the strongest positive predictor (+2 points).
• Prior PCI (+1) and CHF/low EF (+2) reflect higher ischemic risk and thus benefit from prolonged DAPT.
• Paclitaxel-eluting stents (+1) are associated with higher late stent thrombosis risk vs. newer-generation DES.
• The PRECISE-DAPT score (using HB, WBC, age, creatinine, prior bleeding) is an alternative tool focused on bleeding risk.

Next steps

Score ≥ 2: Continue DAPT for up to 30 months — net clinical benefit (reduced MI, stent thrombosis, stroke > increased bleeding). Score < 2: Discontinue thienopyridine at 12 months — bleeding risk outweighs ischemic benefit. Re-evaluate at each clinical visit. DAPT should NOT be continued beyond 30 months without reassessment.

Evidence

Yeh RW et al. Population-level short- and long-term outcomes of coronary stenting using the DAPT Trial. JAMA. 2016;316(16):1679-1689. The DAPT score was derived from 11,648 patients randomized to 12 vs 30 months of thienopyridine therapy after DES placement. C-statistic for net clinical benefit: 0.70. Endorsed by ACC/AHA focused update on DAPT 2016 (Class IIb, Level B-R).

References

1. Yeh RW et al. Benefits and risks of extended duration dual antiplatelet therapy after PCI in patients with and without acute MI. JAMA. 2015;313(10):1021-1029. — link
2. Mauri L et al. Twelve or 30 months of dual antiplatelet therapy after drug-eluting stents. N Engl J Med. 2014;371(23):2155-2166. — link
3. Levine GN et al. 2016 ACC/AHA Guideline Focused Update on Duration of Dual Antiplatelet Therapy in Patients With Coronary Artery Disease. Circulation. 2016;134(10):e123-e155. — link