Assessment of P2Y12 inhibitor usage and switching in acute coronary syndrome patients undergoing percutaneous coronary revascularization

BackgroundDual antiplatelet therapy is recommended for patients with acute coronary syndrome (ACS) that undergo percutaneous coronary intervention (PCI). However, the effect of switching P2Y12 inhibitors between the loading dose and therapy after discharge is not well described.MethodsThis post-hoc analysis of a prospectively collected registry included 3219 consecutive ACS patients who underwent PCI. Patients were categorized into four groups: clopidogrel at load and discharge (C-C), loading dose of clopidogrel and discharged on prasugrel/ticagrelor (C-PT), loading dose of prasugrel/ticagrelor and discharged on clopidogrel (PT-C), and prasugrel/ticagrelor at load and discharge (PT-PT).ResultsWhile 77.6% of patients received the C-C treatment regimen and 13.6% received the PT-PT strategy, the strategy of P2Y12 switching was fairly common with 6.2% in the PT-C group and 2.6% in the C-PT group. While C-C was the most common treatment regimen, PT-C and PT-PT were more commonly used in STEMI patients than in NSTEMI or unstable angina patients. A significantly lower unadjusted incidence of the composite outcome (death, MI, and repeat revascularization) was appreciated in both the PT-C (1.0%) and PT-PT (2.3%) groups than the C-C group (4.0%). Propensity-score matched analysis still showed significantly reduced risk (HR = 0.22, 95% CI 0.05-0.93, p = 0.04) in the PT-C group vs. a matched group of C-C controls.ConclusionsThe strategy of utilizing a newer P2Y12 inhibitor and then switching to clopidogrel in ACS patients following PCI is used with some frequency in routine clinical practice and further studies should evaluate the safety and efficacy of such a strategy.