Ticagrelor effectively inhibits platelet aggregation in comatose survivors of cardiac arrest undergoing primary percutaneous coronary intervention treated with mild therapeutic hypothermia

BACKGROUND: Mild therapeutic hypothermia (MTH) is believed to reduce the effectiveness of antiplateletdrugs. Effective dual-antiplatelet therapy after percutaneous coronary intervention (PCI) is mandatoryto avoid acute stent thrombosis. The effectiveness of ticagrelor in MTH-treated out-of-hospital cardiacarrest (OHCA) survivors is still a matter of debate. The aim of the study was to evaluate the impactof MTH on the platelet-inhibitory effect of ticagrelor in comatose survivors of OHCA treated with primaryPCI. METHODS: Eighteen comatose survivors of OHCA with acute coronary syndrome undergoing immediatePCI treated with MTH were compared with 14 patients with uncomplicated primary myocardial infarctionafter PCI, matched for gender and age, in a prospective, single-center, observational study. Plateletaggregation was evaluated using VerifyNow P₂Y₁₂ point-of-care testing at 3 time points: admission (T₀),during MTH (T₁), and 48–72 h after rewarming (T₂). RESULTS: Ticagrelor effectively inhibits platelet aggregation in OHCA patients subjected to MTH andin all patients in the control group. The effectiveness of ticagrelor did not differ between the MTH groupand the control group (p = 0.581). In 2 cases in the MTH population, the platelet response to ticagrelorwas inadequate, and in one of them it remained insufficient during the re-warming phase. There wasno stent thrombosis in these patients. CONCLUSIONS: The present study confirmed the effectiveness of ticagrelor to inhibit platelets in myocardialinfarction patients after OHCA treated with primary PCI undergoing hypothermia. The use ofcooling was not associated with an increased risk of stent thrombosis.