Angiographic and platelet reactivity outcomes with prasugrel 60 mg pretreatment and clopidogrel 600 mg pretreatment in primary percutaneous coronary intervention

Pretreatment with 60 mg of prasugrel is more effective than 300 mg of clopidogrel in reducing thrombotic complications with primary percutaneous coronary intervention (PCI). We compared angiographic outcomes and platelet reactivity between treatment with 60 mg of prasugrel and 600 mg of clopidogrel administered before primary PCI. In this single centre non-randomized study, 65 consecutive Asian patients with ST-elevation myocardial infarction (STEMI) received 60 mg of prasugrel before primary PCI. The pre- and post-PCI corrected thrombolysis in myocardial infarction frame count (CTFC) and the 8-h post-treatment platelet vasodilator-stimulated phosphoprotein (VASP) index was compared with a matched historical Asian STEMI cohort (n = 65) receiving 600 mg of clopidogrel pretreatment. Comparing the prasugrel and clopidogrel groups, the mean age was 54.1 ± 10.2 versus 55.5 ± 11.8 years, P = 0.238, and the mean body mass index was 24.6 ± 2.0 versus 24.7 ± 2.8 kg m⁻², P = 0.393. The mean pre-PCI CTFC was 82.1 ± 30.2 versus 86.1 ± 27.6, P = 0.045, and the mean post-PCI CTFC was 21.1 ± 13.9 versus 20.1 ± 9.2, P = 0.309. Pre-PCI coronary thrombi were visualised in 6.3 versus 18.1 %, P = 0.038. The median VASP index was 22.2 ± 24.5 versus 70.5 ± 17.5 %, P < 0.001, and high on-treatment platelet reactivity (VASP index > 50 %) was observed in 13.8 versus 84.3 %, P = 0.001. Rescue intracoronary glycoprotein inhibitors were administered to 29.7 versus 51.0 %, P = 0.018, respectively. Treatment with 60 mg of prasugrel before primary PCI was associated with lower platelet reactivity, a modest trend towards better pre-PCI angiographic outcomes, less pre-PCI coronary thrombi and less rescue glycoprotein inhibitor use compared with 600 mg of clopidogrel. The very high frequency of high on-clopidogrel platelet reactivity with 600 mg of clopidogrel in this Asian STEMI cohort deserves further study.