The impact of periprocedural myocardial infarction on mortality in older adults with non-ST-segment elevation acute coronary syndrome: a pooled analysis of the FRASER and HULK studies

AIMS: The prognostic implication of periprocedural myocardial infarction (MI) in older patients has been less investigated. The aim of this study is to assess the relationship between large periprocedural MI and long-term mortality in older patients with non-ST-segment elevation acute coronary syndrome (NSTEACS) undergoing percutaneous coronary intervention (PCI). METHODS: This is a pooled analysis of older NSTEACS patients who were included in the FRASER and HULK studies. Periprocedural MI was defined in agreement with the Society for Cardiovascular Angiography and Interventions definition. The primary outcome was all-cause mortality. The secondary outcome was cardiovascular mortality. The predictors of periprocedural MI and the relationship with scales of physical performance, namely Short Physical Performance Battery and grip strength, were also investigated. RESULTS: The study included 586 patients. Overall, periprocedural MI occurred in 24 (4.1%) patients. After a median follow-up of 1023 (740-1446) days, the primary endpoint occurred in 94 (16%) patients. After multivariable analysis, periprocedural MI emerged as an independent predictor of all-cause mortality (hazard risk 4.30, 95% confidence interval 2.27-8.12). This finding was consistent for cardiovascular mortality (hazard risk 7.45, 95% confidence interval 3.56-15.67). SYNTAX score, multivessel PCI and total stent length were independent predictors of large periprocedural MI. At hospital discharge, patients suffering from periprocedural MI showed poor values of Short Physical Performance Battery and grip strength as compared with others. CONCLUSION: In a cohort of older NSTEACS patients undergoing PCI, large periprocedural MI occurred in around 4% of patients and was associated with long-term occurrence of all-cause and cardiovascular mortality. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: NCT02324660 and NCT03021044