Aims: In the CHAMPION PHOENIX trial, the potent, rapidly acting, intravenous platelet adenosine diphosphate receptor antagonist cangrelor reduced the 48-h incidence of major adverse cardiac events (MACE; death, myocardial infarction, stent thrombosis, or ischaemia-driven revascularization) compared with a loading dose of clopidogrel in patients undergoing percutaneous coronary intervention (PCI). We sought to determine whether the efficacy of cangrelor during PCI varies in patients with simple vs. complex target lesion coronary anatomy.
Methods and results: Blinded angiographic core laboratory analysis was completed in 10 854 of 10 942 (99.2%) randomized patients in CHAMPION PHOENIX (13 418 target lesions). Outcomes were analysed according to the number of angiographic PCI target lesion high-risk features (HRF) present (bifurcation, left main, thrombus, angulated, tortuous, eccentric, calcified, long, or multi-lesion treatment). The number of patients with 0, 1, 2, and ≥3 HRFs was 1817 (16.7%), 3442 (31.7%), 2901 (26.7%), and 2694 (24.8%), respectively. The 48-h MACE rate in clopidogrel-treated patients increased progressively with lesion complexity (from 3.3% to 4.4% to 6.9% to 8.7%, respectively, P < 0.0001). Cangrelor reduced the 48-h rate of MACE by 21% {4.7% vs. 5.9%, odds ratio (OR) [95% confidence interval (95% CI)] 0.79 (0.67, 0.93), P = 0.006} compared with clopidogrel, an effect which was consistent regardless of PCI lesion complexity (Pinteraction = 0.66) and presentation with stable ischaemic heart disease (SIHD) or an acute coronary syndrome (ACS). By multivariable analysis, the number of high-risk PCI characteristics [OR (95% CI) 1.68 (1.20, 2.36), 2.78 (2.00, 3.87), and 3.23 (2.33, 4.48) for 1, 2, and 3 HRFs compared with 0 HRFs, all P < 0.0001] and treatment with cangrelor vs. clopidogrel [OR (95% CI) 0.78 (0.66, 0.92), P = 0.004] were independent predictors of the primary 48-h MACE endpoint. Major bleeding rates were unrelated to lesion complexity and were not increased by cangrelor.
Conclusion: Peri-procedural MACE after PCI is strongly dependent on the number of treated high-risk target lesion features. Compared with a loading dose of clopidogrel, cangrelor reduced MACE occurring within 48 h after PCI in patients with SIHD and ACS regardless of baseline lesion complexity. The absolute benefit:risk profile for cangrelor will therefore be greatest during PCI in patients with complex coronary anatomy.
Clinicaltrials.gov identifier: NCT01156571.