Reassessing After-Hour Arrival Patterns and Outcomes in ST-Elevation Myocardial Infarction

Differences in after-hours capability or performance of ST-elevation myocardial infarction (STEMI) centers has the potential to impact outcomes of patients presenting outside of regular hours.

Using a prospective observational study, we analyzed all 1,247 non-transfer STEMI patients treated in 15 percutaneous coronary intervention (PCI) facilities in Dallas, Texas, during a 24-month period (2010-2012). Controlling for confounding factors through a variety of statistical techniques, we explored differences in door-to-balloon (D2B) and in-hospital mortality for those presenting on weekends vs. weekdays and business vs. after hours.

Patients who arrived at the hospital on weekends had larger D2B times compared to weekdays (75 vs. 65 minutes; KW=48.9; p<0.001). Patients who arrived after-hours had median D2B times >16 minutes longer than those who arrived during business hours and a higher likelihood of mortality (OR 2.23, CI [1.15-4.32], p<0.05).

Weekends and after-hour PCI coverage is still associated with adverse D2B outcomes and in-hospital mortality, even in major urban settings. Disparities remain in after-hour STEMI treatment.