Percutaneous coronary intervention (PCI)-related myonecrosis is frequent and can affect the long-term prognosis of patients. To our knowledge, ticagrelor has not been evaluated in elective PCI and could reduce periprocedural ischaemic complications compared with clopidogrel, the currently recommended treatment. The aim of the ALPHEUS study was to examine if ticagrelor was superior to clopidogrel in reducing periprocedural myocardial necrosis in stable coronary patients undergoing high-risk elective PCI.