en Cardiovascular Cardiovascular Original Research Original Research <span style="font-size:13pt"><span style="text-justify:kashida"><span style="text-kashida:0%"><span style="text-autospace:none"><span new="" roman="" style="font-family:" times=""><span style="font-style:italic"><b>&nbsp;&nbsp;</b><b><span style="font-size:9.0pt"><span style="font-style:normal">&nbsp; Background: </span></span></b><span style="font-size:9.0pt"><span style="font-style:normal">Little is known about the current scenario of acute myocardial infarction (AMI) under primary angioplasty; Transferred by emergency medical services and self-referred patients in Iran.</span></span></span></span></span></span></span></span><br> <span style="font-size:13pt"><span style="text-justify:kashida"><span style="text-kashida:0%"><span style="text-autospace:none"><span new="" roman="" style="font-family:" times=""><span style="font-style:italic"><span style="font-size:9.0pt"><span style="font-style:normal">&nbsp;&nbsp; <b>Methods:</b> The study population consisted of AMI patients with ST-segment elevation myocardial infarction (STEMI) who were consecutively admitted with Emergency Medical Services (EMS) or directly in the first six months of 2021 in 2 PCI-capable selected hospitals in Tehran. We analyzed the pattern of transfer by emergency medical services and compared in-hospital treatments and outcomes between transferred patients and self-referred patients in Tehran. Statistical comparisons were performed using chi‑square, t‑tests, or Mann&ndash;Whitney U tests, and multivariable logistic regression was used to assess factors associated with in‑hospital mortality, with significance set at </span></span><span style="font-size:9.0pt">P</span><span style="font-size:9.0pt"><span style="font-style:normal"><0.05.</span></span></span></span></span></span></span></span><br> <span style="font-size:13pt"><span style="text-justify:kashida"><span style="text-kashida:0%"><span style="text-autospace:none"><span new="" roman="" style="font-family:" times=""><span style="font-style:italic"><span style="font-size:9.0pt"><span style="font-style:normal">&nbsp;&nbsp; <b>Results:</b> In-hospital mortality was higher in the self-referred than in patients transferred by EMS (9.8% versus 5.2%) (</span></span><span style="font-size:9.0pt">P</span><span style="font-size:9.0pt"><span style="font-style:normal">=0.014). The average door-to-balloon (DTB) time in the self-referred patients was significantly higher (60.26&plusmn;59.0 minutes vs 49.30&plusmn;48.82 minutes) (</span></span><span style="font-size:9.0pt">P</span><span style="font-size:9.0pt"><span style="font-style:normal">=0.020). Results show that the average DTB time of patients who died in the hospital was higher than that of patients who were alive in the self-referred patients. The average time from pain onset to Balloon (OTB) in the self-referred patients and those transferred by EMS was 348.74&plusmn;316.07 minutes and 226.26&plusmn;183.15 minutes, respectively (</span></span><span style="font-size:9.0pt">P</span><span style="font-size:9.0pt"><span style="font-style:normal"><0.001). Multivariable logistic regression models the chance of in-hospital mortality in patients who self-referred is 2.17 times that of patients who were transferred by EMS, which is statistically significant (</span></span><span style="font-size:9.0pt">P</span><span style="font-size:9.0pt"><span style="font-style:normal">=0.008).</span></span></span></span></span></span></span></span><br> <span style="font-size:13pt"><span style="text-justify:kashida"><span style="text-kashida:0%"><span style="text-autospace:none"><span new="" roman="" style="font-family:" times=""><span style="font-style:italic"><span style="font-size:9.0pt"><span style="font-style:normal">&nbsp;&nbsp; <b>Conclusion:</b> Our results indicated that there are significant differences in treatment delay and use of early revascularization, such as time of first medical contact (FMC) to the device, time of pain onset to Balloon (OTB), and DTB time between transferred-by-EMS patients and self-referred patients. </span></span></span></span></span></span></span></span><br> &nbsp; Acute myocardial infarction, Emergency services, Direct admission, Health outcomes 689 698 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-3682-3&slc_lang=en&sid=1 Zahra Kolivand z_kolivand@gmail.com 200319475328460099103 200319475328460099103 No School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Samad Azari samadazari1010@gmail.com 200319475328460099104 200319475328460099104 No Health Management and Economics Research Center, Health Management Research Institute, Iran University of Medical Sciences, Tehran, Iran Parisa Hasani Sharamin parisahasaniems@gmail.com 200319475328460099105 200319475328460099105 No National Emergency Medical Service Organization, Tehran, Iran Zahra Shajari zahra.shajari@gmail.com 200319475328460099106 200319475328460099106 No Department of Cardiology, Sina Hospital, Tehran University of Medical Sciences, Tehran, Iran Mostafa Rouzitalab rouzitalab@gmail.com 200319475328460099107 200319475328460099107 No Rajaei Cardiovascular and Medical Research Center, Iran University of Medical Sciences, Tehran, Iran Negar Omidi negar.omidi@gmail.com 200319475328460099108 200319475328460099108 No Tehran Heart Center, Cardiovascular Disease Research Institute, Tehran University of Medical SciencesTehran, Iran Peyman Saberian pymnsbrin82@gmail.com 200319475328460099109 200319475328460099109 Yes Department of Anesthesiology, Imam Khomeini Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran