Factors Related To Prehospital And In-hospital Time Delay Of Emergency Percutaneous Interventional Therapy In Acute ST-segment Elevation Myocardial Infarction

Objectives:To investigate potential factors related to pre-hospital and in-hospital time delay of primary percutaneous coronary interventional therapy in acute ST-segment elevation myocardial infarction(STEMI).Methods:From December2012to November2013, a total of269eligible patients who are treated with primary percutaneous coronary interventional for acute ST-segment elevation myocardial infarction in Tianjin Chest Hospital were enrolled in the present study. Patients were grouped by the pre-hospital(<6hours and>6hours from onset of symptom to balloon) and in-hospital(door to balloon time<90min and>90min) time delay. Clinical characteristics, such as time course of from the symptom to the therapy, basal interventional therapy, expenses and outcomes of the patients’were recorded and analyzed.Results:1. Prehospital time delay: More patients with diabetic mellitus(DM) were found in group of>6hours (18.8%in≤6hours group vs.37.3%in>6hours group, P=0.002). More patients with nocturnal-onset STEMI trend to present later than those presented during daytime(19.3%in≤6hours group vs.52.2%in>6hours group, P<0.001). Target lesions are longer in patients who presented later than6hours(30.7±16.0mm in≤6hours group vs.38.6±20.1mm in>6hours group, P=0.003). Whereas, DM(OR=2.824,95%CI:1.472-5.420, P=0.002) and nocturnal-onset STEMI(OR=4.837,95%CI:2.623-8.920,＜0.001) were independent factors of pre-hospital time delay according to Logistic Regression.2. In-hospital time delay: symptoms onset during night(12.8%in≤90min group vs.30.0%in>90min group, p=<0.026), medical contact to decision time (20.2±25.1min in≤90min group vs.182.1±210.9in>90min group,＜0.001) are different between the two groups. More patients underwent trans-radial interventions (28.2%in<90min group vs.9.1%in>90min group, P=0.001) and more single-vessel coronary disease (51.3%in<90min group vs.23.0%in>90min group, P＜0.001) were found in<90min group. Whereas, multi-vessel coronary disease (OR=3.85695%CI:1.567-9.490, P=0.003), from medical contact to decision time are independent factors for in-hospital delay (OR=1.043,95%CI:1.027-1.058, P＜0.001) were independent factors of in-hospital time delay according to Logistic Regression.Conclusions:Factors of time delay for primary percutaneous coronary intervention therapy might be different between pre-hospital and in-hospital factors. Diabetic Mellitus and nocturnal-onset STEMI might be an important factor of pre-hospital delay for primary percutaneous coronary intervention therapy. Multi-vessel coronary disease and the time from medical contact to decision might be the independent factors of in-hospital delay for primary percutaneous coronary intervention therapy.