A 52-year-old man with acute inferior wall STEMI undergoes successful primary percutaneous coronary intervention (PCI) with stent placement. At the end of the procedure, he is started on dual antiplatelet therapy. Which of the following is the drug of choice for long-term P2Y12 inhibition in this patient?

Explanation

## P2Y12 Inhibitor Choice in Post-PCI STEMI **Key Point:** Ticagrelor 60 mg twice daily is the preferred P2Y12 inhibitor for long-term dual antiplatelet therapy (DAPT) after PCI in acute coronary syndrome (ACS) / STEMI, based on superior outcomes in landmark trials. ### Why Ticagrelor 60 mg BD? 1. **Superior antiplatelet potency** — Ticagrelor is a direct, reversible P2Y12 antagonist with faster onset and offset compared to clopidogrel (thienopyridine). 2. **PLATO trial evidence** — In the PLATO trial (2009), ticagrelor 60 mg BD reduced cardiovascular death, MI, and stent thrombosis compared to clopidogrel 75 mg daily in ACS patients, with similar major bleeding rates. 3. **Reduced stent thrombosis** — Ticagrelor has a lower incidence of definite/probable stent thrombosis (1.3% vs 1.9% with clopidogrel). 4. **Guideline recommendation** — ESC and ACC/AHA guidelines recommend ticagrelor or prasugrel as preferred P2Y12 inhibitors over clopidogrel in ACS/STEMI after PCI. ### Comparative Profile of P2Y12 Inhibitors | Agent | Class | Onset | Offset | Dosing | Stent Thrombosis | Bleeding | Guideline Status | | --- | --- | --- | --- | --- | --- | --- | --- | | **Ticagrelor** | Cyclopentyl-triazolo-pyrimidine | Fast (30 min) | Fast (3–5 days) | 180 mg LD, 60 mg BD | Lowest | Similar | **Preferred** | | Prasugrel | Thienopyridine | Moderate (30–60 min) | Slow (7–10 days) | 60 mg LD, 5 mg daily | Low | Slightly higher | **Preferred** | | Clopidogrel | Thienopyridine | Slow (2–4 hrs) | Slow (5–7 days) | 600 mg LD, 75 mg daily | Higher | Lower | Alternative | | Ticlopidine | Thienopyridine | Slow (3–5 days) | Slow (8–10 days) | 250 mg BD | High | Moderate | **Obsolete** | **High-Yield:** Ticagrelor and prasugrel are now preferred over clopidogrel in ACS/STEMI. Ticagrelor is slightly more commonly used due to broader applicability (prasugrel is contraindicated in prior stroke/TIA and in patients >75 years or <60 kg). ### DAPT Duration **Clinical Pearl:** Standard DAPT duration after STEMI is 12 months (aspirin indefinitely + P2Y12 inhibitor for 12 months). In high-bleeding-risk patients, 6 months may be considered; in very high ischemic-risk patients, extended DAPT beyond 12 months may be considered. **Mnemonic:** **PLATO** = **P**rasugrel/**L**oading/**A**cute/**T**hienopyridine/**O**utcomes — landmark trial showing ticagrelor superiority in ACS. **Warning:** Do not confuse ticagrelor (reversible, direct P2Y12 antagonist) with clopidogrel (irreversible thienopyridine). Ticagrelor has faster onset and offset, making it superior in acute coronary syndromes. [cite:Harrison 21e Ch 297; ESC Guidelines on ACS (2020)]