Tehran University of Medical Sciences The Research in Heart Yield and Translational Medicine (RHYTHM) 3115-7270 9 3 2015 10 11 115 119 EN Ahmad Sharafi Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Hamid Reza Pour-Hosseini Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Arash Jalali Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Mojtaba Salarifar Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Ebrahim Nematipour Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Mohsen Shojanasab Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Hassan Aghajani Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Alireza Amirzadegan Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Younes Nozari Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Nozari Alidoosti Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Alimohammad Haji-Zeinali Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Seyed Ebrahim Kassaian Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. 2015 10 11 2015 10 11 Background: Controversy persists over the potential benefits/harms of opium consumption in coronary heart disease. This study investigated the association between 12 months' major adverse cardiac events (MACE) and pre-procedural opium consumption among patients undergoing percutaneous coronary intervention (PCI). Methods: Retrospectively, 1545 consecutive men who underwent PCI between 21st  June 2009 and 20th June 2010 at Tehran Heart Center and were registered in the PCI Databank were entered into this cohort study. The occurrence of MACE, defined as cardiac death, non-fatal myocardial infarction, and need for target vessel revascularization (TVR) or target lesion revascularization (TLR), was compared between two groups of opium consumers and non-consumers in 350 (22.7%) patients. Results: Sixty-four (0.86%) patients expired within 12 months. After adjustment for potential confounders, analysis revealed that opium consumption had no significant relationship with 12 months' MACE [11(3.1%) vs. 53(4.4%); p value= 0.286, among opium users vs. non users, respectively].Furthermore, the different components of MACE, including target vessel revascularization, target lesion revascularization, coronary artery bypass graft, and non-fatal myocardial infarction, were not significantly related to opium use. Conclusion: Pre-procedural opium usage in patients undergoing PCI was not associated with 12 months' MACE. https://rhythm.tums.ac.ir/index.php/jthc/article/view/339 https://rhythm.tums.ac.ir/index.php/jthc/article/download/339/332