Clinical outcomes in patients with acute myocardial infarction treated with primary percutaneous coronary intervention stratified according to duration of pain-to-balloon time and type of myocardial infarction

BACKGROUND: Based on the clinical outcomes of patients with ST-segment elevation myocardial infarction(STEMI) and non-ST-segment elevation myocardial infarction (NSTEMI), treated with primary percutaneouscoronary intervention (pPCI), this study intended to assess mortality and major adverse cardiac andcerebrovascular event (MACCE) rates according to duration of pain-to-balloon (PTB) time and type of MI. METHODS: This is a retrospective cohort study based on the prospectively collected ORPKI registry whichcovers PCIs performed in Poland chosen between January 2014 and December 2017. Under assessmentwere 1,994 STEMI and 923 NSTEMI patients. Study endpoints included mortality and MACCE rates(in-hospital, 30-day, 12- and 36-month). Predictors of all-cause mortality in the overall group, STEMIand NSTEMI were assessed by multivariable analysis. RESULTS: Kaplan-Meier survival curve analysis did not reveal significant differences between theSTEMI and NSTEMI group for all-cause mortality or MACCE at the 36-month follow-up. While inthe long PTB time group, MACCE rate was significantly greater in STEMI patients when compared toNSTEMI (p = 0.004). Among STEMI patients, the short, medium and long PTB time groups differedsignificantly in the rate of all-cause mortality (p = 0.006) and MACCE (p = 0.04) at 1,095 days offollow-up, which were the greatest in the long PTB time group. CONCLUSIONS: Before considering the length of PTB time, there were no statistically significant differencesin mortality or MACCE frequency between the STEMI and NSTEMI group at 36-month follow-up.Longer PTB times are related to significantly greater mortality at the 36-month follow-up in the STEMI,but not in the NSTEMI group.