The impact of transferring patients with ST-segment elevation myocardial infarction to percutaneous coronary intervention-capable hospitals on clinical outcomes.

Background: Primary percutaneous coronary intervention (PCI) is recommended for ST-segment elevation myocardial infarction (STEMI) patients even when the patient must be transported to a PCI-capable hospital. This study aimed to evaluate the long-term clinical outcomes of STEMI patients who were transferred for primary PCI compared to patients who arrived directly to PCI-capable hospitals. Methods: A total of 3,576 STEMI patients with less than 12 h of symptom onset-to-door time from the Korea Acute Myocardial Infarction Registry were divided into transfer (n = 2,176) and direct-arrival (n = 1,400) groups according to their status. The primary outcome was the composite of major adverse cardiac event (MACE), defined as death, non-fatal myocardial infarction, and revascularization at 1 year. Results: In the transfer vs. the direct-arrival group, the median symptom onset-to-firstmedical contact time was significantly shorter (60 vs. 80 min, p < 0.001), but the median symptom onset-to-door time was significantly longer (194 vs. 90 min, p < 0.001). The median door-to-balloon time was significantly shorter in the transfer group vs. the direct-arrival group (75 vs. 91 min, p < 0.001). Total death and the composite of MACE were not significantly different during hospitalization (5.1 vs. 3.9%, p = 0.980; 5.4 vs. 4.8%, p = 0.435, respectively) and at 1-year (8.2 vs. 6.6%, p = 0.075; 13.7 vs. 13.9%, p = 0.922, respectively). Conclusions: Transferring STEMI patients to PCI-capable hospitals with a time delay did not affect clinical outcomes after 1 year. This study suggests that inter-hospital transfer should be encouraged even with delay for STEMI patients who require primary PCI in areas with a similar geographic accessibility.