en Clinical Medicine Clinical Medicine گزارش موردی Case Report Article <p style="text-align: justify;"><span style="font-size:16px;"><span style="font-family:Times New Roman;"><span style="line-height:200%"><span style="unicode-bidi:embed"><span style="line-height:200%">We herein describe a 34-year-old woman with a persistent left superior vena cava (PLSVC) impinging on the posterior wall of the left atrium, subdivided by a membrane at the distal part of the impingement. In this patient, a much dilated coronary sinus due to the PLSVC resulted in a membrane-like structure in the posterior wall of the left atrium with the appearance of the <i>cor triatriatum</i> in transthoracic echocardiography (ie, a <i>pseudo cor triatriatum</i>). Although the PLSVC is a common malformation of the superior systemic vein, its aforementioned presentation is rare.</span></span></span></span></span></p> Persistent Left Superior Vena Cava, Cor Triatriatum, Coronary Sinus, Left Atrial Function 570 572 http://journal.zums.ac.ir/browse.php?a_code=A-10-5074-1&slc_lang=en&sid=1 Zahra Khajali khajaliz@yahoo.com 5200319475328460073710 5200319475328460073710 No Echocardiography Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran Nasibeh Mohammadi n.nasibeh@gmail.com 5200319475328460073711 5200319475328460073711 Yes Echocardiography Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran Raheleh Kaviani rahelehkaviani@yahoo.com 5200319475328460073712 5200319475328460073712 No Echocardiography Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran Hamidreza Pouraliakbar Hamidpou@yahoo.com 5200319475328460073713 5200319475328460073713 No Cardiovascular Imaging Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran Niloufar Parsa dr.niloufar.parsa@gmail.com 5200319475328460073714 5200319475328460073714 No Echocardiography Research Center, Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran