Definitions of peri-procedural myocardial infarction and the association with one-year mortality: Insights from CHAMPION trials

Background: Controversies exist over the appropriate definition for peri-procedural myocardial infarction (PPMI) and its association with mortality. This study aims to evaluate one-year survival following percutaneous coronary intervention (PCI) and the association of different definitions of PPMI with survival among patients with stable angina (SA) or acute coronary syndrome (ACS) in the contemporary era. Methods: We used data from the CHAMPION PLATFORM and CHAMPION PCI trials of patients undergoing PCI and conducted univariable and multivariable Cox proportional hazard regression models to evaluate mortality risk during the first year after PCI. A blinded events committee adjudicated suspected PPMI defined by biomarker elevations ≥3× the upper limit of normal (ULN) or new Q-waves. We further analyzed PPMI by the magnitude of CK-MB elevation ([a] 3 to <5× ULN, [b] 5 to <10× ULN, [c] ≥10× ULN) or by the 2^nd universal definition of myocardial infarction (UDMI_CK-MB) excluding patients with evidence of myocardial infarction (MI) prior to PCI. Results: Of 13,968 patients, 11% initially presented with SA, and 89% with ACS. One-year mortality was 3.4% (SA: 1.5%; ACS: 3.6%). PPMI occurred in 6.3% of the patients (3 to <5× ULN: 2.5%; 5 to <10× ULN: 2.1%; ≥10× ULN: 1.6%; UDMI_CK-MB: 2.7%). After multivariable adjustment, a significantly higher risk of one-year mortality was observed for patients with PPMI compared with patients without PPMI (HR 2.35 [1.74–3.18], p < 0.001; 3 to <5× ULN: 1.55 [0.92–2.62], p = 0.10; 5 to <10× ULN: 1.22 [0.67–2.20], p = 0.52; ≥10× ULN: 4.78 [3.06–7.47], p < 0.001; UDMI_CK-MB: 2.19 [1.29–3.73], p = 0.004). Conclusion: PPMI occurred in 6.3% of the patients and was associated with increased risk of death within one year. Survival was not significantly impacted by PPMI if defined by periprocedural CK-MB elevations <10× ULN alone and without additional evaluation of symptoms or evidence of ischemia. These findings highlight the importance of PPMI for long-term outcome in the contemporary era and of its definition in the planning and interpretation of clinical trials.