Determinants of Prehospital Delay in Patients with Acute Myocardial Infarction

Determination of pre-hospital delay time of patients with acute myocardial infarction and seeking ways of speeding up the time for reperfusion is an important factor to lower mortality in these patients. This is a cross-sectional study to determine pre-hospital delay time, its components, and related causes and conditions, obtained in 375 patients with prolonged chest pain referred to four hospitals of Tehran University of Medical Sciences. Means of transport to hospital, reasons of ambulance disuse, decision time by the patient and finally the entire time of pre-hospital delay were specified. Suspected factors related to delays of more than 2 and 6 h were scrutinized with chi-square test. Rate of ambulance utility (18.9%) directly correlated with age of patients (P<0.05). Principal motives to disuse ambulance insuccession were unrememberance (33.7%), access to private vehicle (32.8%) and supposition of sufficient speed of personal reference (18.9%). Pre-hospital delay time was 8.1 ± 9.1 h (mean ± SD) in whole patients and 7.6 ± 9.1 h in those with acute myocardial infarction. Delays of more than 2 and 6 h occurred in 67.5% and 33.6% of patients, respectively. Decision time constitute three fourth of whole pre-hospital delay and was correlated with female gender, older age, history of diabetes, lower level of literacy and nocturnal onset of symptoms. In conclusion, a significant number of patients with acute myocardial infarction have pre-hospital delay of more than 2 and even 6 h, when golden time for thrombolytic therapy has already been elapsed. Acta Medica Iranica, 42(1): 50-54; 2004 Key word: Myocardial infarction , myocardial reperfusion, hospital referral, ambulance