ISSN 2996-8215
International Journal of Cardiology | Vol. 10, No. 1, January 2019 | pp. 1–8
DOI: 10.46882/2019/IJC/000118
Original Research Article
Adjusted High-Dose Clopidogrel Maintenance Regimen in Patients with High Post-Treatment Platelet Reactivity Undergoing PCI
Ji-Hoon Kim¹, Min-Soo Park¹, Sung-Hoon Choi²
¹Department of Cardiology, Severance Cardiovascular Hospital, Yonsei University College of Medicine, Seoul, South Korea
²Division of Electrophysiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea
Abstract:
High post-treatment platelet reactivity (HPPR) following standard clopidogrel therapy is associated with an increased risk of ischemic events after percutaneous coronary intervention (PCI). Adjusting the antiplatelet regimen based on platelet function testing could mitigate this risk. This randomized open-label trial evaluated whether a high-dose clopidogrel regimen reduces major adverse cardiovascular events (MACE) in patients with documented HPPR undergoing PCI. We screened 650 patients scheduled for elective PCI using the VerifyNow P2Y12 assay. HPPR was defined as a P2Y12 reaction unit (PRU) value greater than 230. A total of 180 patients identified with HPPR were randomized 1:1 to either the high-dose group (clopidogrel 150 mg daily, n = 90) or the standard-dose group (clopidogrel 75 mg daily, n = 90) for 6 months. The primary endpoint was a composite of cardiac death, non-fatal myocardial infarction, or definite stent thrombosis at 6 months. At 6 months, high-dose clopidogrel significantly reduced the mean PRU value from 265 ± 24 to 192 ± 31 (p < 0.001), whereas platelet reactivity remained elevated in the standard-dose group (258 ± 22 PRU). The primary composite endpoint occurred in 4.4% of the high-dose cohort compared to 12.2% of the standard-dose cohort (p = 0.04). No significant difference was observed in the incidence of TIMI major bleeding complications (2.2% vs. 1.1%, p = 0.56). Adjusting to a high-dose clopidogrel maintenance regimen in patients with verified high post-treatment platelet reactivity significantly enhances platelet inhibition and safely reduces short-term ischemic events following PCI.
Keywords: Percutaneous coronary intervention, Clopidogrel, Platelet reactivity, VerifyNow, Stent thrombosis, Antiplatelet therapy
Received: October 10, 2013; Revised: November 24, 2013; Accepted: December 15, 2013; Published: January 18, 2019