Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 42 1 2004 02 15 50 54 M. Alidoosti 2015 09 28 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 https://acta.tums.ac.ir/index.php/acta/article/view/2689 https://acta.tums.ac.ir/index.php/acta/article/download/2689/2671