Trends in treatment delays for patients with acute ST-elevation myocardial infarction treated with primary percutaneous coronary intervention

Background: Treatment delay is an important prognostic factor for patients with acute ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI). We aimed to determine recent trends in these delays and factors associated with longer delays. Methods: We compared two datasets collected in Helsinki University Central Hospital in 2007-2008 (HUS-STEMI I) and 2011-2012 (HUS-STEMI II), a total of 500 patients treated with primary PCI within 12 hours of the onset of symptoms. Results: Delays of the emergency medical system (EMS) were longer in HUS-STEMI I than II (medians 81 vs. 67 min, respectively, p < 0.001). Although door-to-balloon times were longer in the later dataset (33 vs. 48 min, p < 0.001) most of the patients (75.3% vs. 62.8%, respectively, p = 0.010) were treated within the recommendation (< 60 min) of the European Society of Cardiology (ESC). In HUS-STEMI II, patient arrival at the hospital during off-hours was associated with longer door-to-balloon time (40 and 57.5 min, p = 0.001) and system delay (111 and 127 min, p = 0.009). However, in HUS-STEMI I, arrival time did not impact the delays. Longer system delay was associated with higher mortality rates. Conclusions: Though the delays inside the hospital have increased they are still mostly within the ESC guidelines. Still, only about half of the patients are treated within a system delay of recommended two hours. Albeit our results are good in comparison with previous studies, further efforts for decreasing the delays particularly within the EMS should be established.