Objective: Our study aimed to analyse the hospital mortality of patients admitted in- and off-regular working hours with ST-elevation myocardial infarction (STEMI) within the special logistical setting of the urban area of the city of Berlin.
Background: There is a debate whether patients with acute myocardial infarction admitted to hospital outside regular working hours experience higher mortality rates than those admitted within regular working hours.
Methods: This study analyses data from the Berlin Myocardial Infarction Registry and comprises 2,131 patients with STEMI and treated with percutaneous coronary intervention (PCI) in 2004-2007. Data of patients admitted during in- and off-regular working hours were compared.
Results: There was significant difference in door-to-balloon time (median in-hours: 79 min; median off-hours: 90 min, p < 0.001) and in hospital mortality (in-hours: 4.3%; off-hours: 6.8%, p = 0.020) between STEMI patients admitted in- and off-hours for treatment with PCI. After adjustment, admission off-hours remained an independent predictor for in-hospital death for patients (OR = 2.50; 95% CI 1.38-4.56). In patients with primary care from physician-escorted Emergency Medical Services (EMS), door-to-balloon time was reduced by 10 min for in-hours as well as off-hours patients. The difference in hospital mortality between off-hour and in-hour admission was reduced to a non-significant OR = 1.61 (95% CI 0.79-3.27).
Conclusions: In conclusion, patients admitted off-hours experienced longer door-to-balloon times and higher hospital mortality than did those admitted in-hours. The differences observed between patients admitted in-hours and off-hours were reduced through physician-escorted EMS reflecting the influence of optimized STEMI care.