Tehran University of Medical Sciences The Research in Heart Yield and Translational Medicine (RHYTHM) 3115-7270 8 3 2015 10 11 146 151 EN Hamid Reza Sanati Cardiovascular Intervention Research Center, Shaheed Rajaei Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. Mohammad Parsa Mahjoob Cardiovacsular Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Ali Zahedmehr Cardiovascular Intervention Research Center, Shaheed Rajaei Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. Farshad Shakerian-Ghahferokhi Cardiovascular Intervention Research Center, Shaheed Rajaei Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. Ata Firoozi Cardiovascular Intervention Research Center, Shaheed Rajaei Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. Reza Kiani Cardiovascular Intervention Research Center, Shaheed Rajaei Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. Zohreh Sadeghi Cardiovascular Intervention Research Center, Shaheed Rajaei Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. Abolfath Alizadeh-Diz Cardiac Electrophysiology Research Center, Shaheed Rajaei Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. Hooman Bakhshandeh-Abkenar Cardiovascular Intervention Research Center, Shaheed Rajaei Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran. 2015 10 11 2015 10 11 Background: Although  percutaneous  coronary  intervention  (PCI)  improves  outcomes  compared  to  thrombolysis,  a substantial number of ST-elevation myocardial infarction (STEMI) patients do not achieve optimal myocardial reperfusion. This study was designed to evaluate factors related to suboptimal myocardial reperfusion after primary PCI in patients with STEMI. Methods: Totally, 155 patients (124 men; mean age = 56.6 ± 11.03 years, range = 31- 85 years) with STEMI undergoing primary PCI were retrospectively studied. Additionally, the relationships between the occurrence of reperfusion failure and variables such as age, sex, cardiac risk factors, family history, Body Mass Index, time of symptom onset, ejection fraction, previous PCI, coronary artery bypass graft surgery or previous myocardial infarction, and angiographic data were analyzed. Results: Procedural success was 97.1% and complete ST resolution occurred in 43.2%. Age; cardiac risk factors; family history; body mass index; previous MI, coronary artery bypass graft surgery, or PCI; and use of thrombectomy device and GPIIb/IIIa inhibitor were not the determining factors (p value > 0.05). According to our multivariate analysis, time of symptom onset (OR [95% CI]: 045 [0.2 to 0.98]; p value = 0.044) and ejection fraction (OR [95% CI]:0.37 [0.26 to .091]; p value = 0.050) had reverse and male gender had direct significant associations with failed reperfusion (OR [95%CI]:0.34 [0.11 to 1.08]; p value = 0.068). More degrees of ST resolution occurred when the right coronary artery was the culpritvessel (p value = 0.001). The presence of more than three cardiac risk factors was associated with failed reperfusion (p value= 0.050). Conclusion: Considering the initial risk profile of patients with acute STEMI, including time of symptom onset and ejection fraction, as well as the accumulation of cardiac risk factors in a given patient, we could predict failed myocardial reperfusion to design a more aggressive therapeutic strategy. https://rhythm.tums.ac.ir/index.php/jthc/article/view/299 https://rhythm.tums.ac.ir/index.php/jthc/article/download/299/292