Tehran University of Medical Sciences The Research in Heart Yield and Translational Medicine (RHYTHM) 3115-7270 16 1 2021 01 14 31 33 Hakimeh Sadeghian Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Afsaneh Sadeghian Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Bahare Eslami Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. Seyed Hesameddin Abbasi 1Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. 2Bernard Lown Scholar in Cardiovascular Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA. Masoumeh Lotfi-Tokaldany Tehran Heart Center, Tehran University of Medical Sciences, Tehran, Iran. 2020 09 07 2021 01 30 Mucopolysaccharidosis (MPS) syndrome is an inherited metabolic disorder. In more than half of the patients with MPS syndrome, heart valve involvement is reported; however, combined aortic and mitral valve stenosis in MPS syndrome type I-S is very rare. We describe a 39-year-old man with severe mitral and aortic valve stenosis due to MPS syndrome type I-S. Transthoracic and transesophageal echocardiography revealed severe thickening and calcification in the aortic and mitral valves with severe left ventricular hypertrophy. The coronary arteries were normal in angiography. https://jthc.tums.ac.ir/index.php/jthc/article/view/1342 https://jthc.tums.ac.ir/index.php/jthc/article/download/1342/960