Stepwise relationship between delay in percutaneous coronary intervention and long-term mortality in patients with non-ST-segment elevation myocardial infarction

BACKGROUND: Current guidelines recommend coronary catheterization in patients with non-ST- -segment elevation myocardial infarction (NSTEMI) within 24 hours of hospital admission. However, whether there is a stepwise relationship between the time to percutaneous coronary intervention (PCI) and long-term mortality in patients with NSTEMI treated invasively within 24 hours of admission has not been established yet. AIMS: The study aimed to evaluate the association between door-to-PCI time and all-cause mortality at 12 and 36 months in NSTEMI patients presenting directly to a PCI-capable center who underwent PCI within the first 24 hours of hospitalization. METHODS: We analyzed data of patients hospitalized for NSTEMI between 2007-2019, included in the nationwide registry of acute coronary syndromes. Patients were stratified into twelve groups based on 2-hour intervals of door-to-PCI time. The mortality rates of patients within those groups were adjusted for 33 confounding variables by the propensity score weighting method using overlap weights. RESULTS: A total of 37 589 patients were included in the study. The median age of included patients was 66.7 (interquartile range [IQR], 59.0-75.8) years; 66.7% were male, and the median GRACE (Global Registry of Acute Coronary Events) score was 115 (98-133). There were increased 12-month and 36-month mortality rates in consecutive groups of patients stratified by 2-hour door-to-PCI time intervals. After adjustment for patient characteristics, there was a significant positive correlation between the time to PCI and the mortality rates (rs = 0.61; P = 0.04 and rs = 0.65; P = 0.02 for 12-month and 36-month mortality, respectively). CONCLUSIONS: The longer the door-to-PCI time, the higher were 12-month and 36-month all-cause mortality rates in NSTEMI patients.