A 47-year-old man diagnosed with mucopolysaccharidosis (MPS) type IS was admitted for chest oppression on effort. Transthoracic and transoesophageal echocardiography showed a highly calcified aortic valve (AV) with a mean gradient of 76 mmHg, AV area of 0.60 cm² (Supplementary material online, Video S1), moderate mitral stenosis with a mean gradient of 8 mmHg, mitral valve (MV) area of 1.42 cm² (Supplementary material online, Video S2), and left ventricular ejection fraction of 79% with no left ventricular dilatation (Supplementary material online, Video S3). Coronary angiography revealed no significant coronary artery stenosis. Although enzyme replacement therapy is an effective treatment for MPS-I, it cannot stop the progression of valvular disorders. Thus, AV and MV replacement and tricuspid annuloplasty were performed. Thickened AV leaflets and a calcified annulus were identified. The MV annulus was also remarkably calcified, and the anterior leaflet thickened and shortened. Myocardial tissue was obtained from the atrial septum during surgery for further examination. Foamy cells (arrows) were observed in the myocardium (Panel A) by light microscopy, just like in the MV tissues (Panels B and C, periodic acid-Schiff stain and immunohistochemistry for CD68, respectively). Electron microscopy revealed that foamy cells in the interstitial space (Panel D, arrows) were macrophages with rich nuclear heterochromatin and foot processes (Panel E). Foamy cell vacuoles, i.e. lysosomes, contained with several different electron densities. Moreover, zebra bodies, degenerated lysosomes and a specific feature of MPS, were identified in cardiomyocytes (Panel F, arrows). Even MPS-IS with a slightly better prognosis than MPS-IH has various myocardial alterations.

中文翻译：

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IS型粘多糖贮积病患者的心肌改变

一名47岁的被诊断患有粘多糖贮积症（MPS）IS的男子因胸部受力而入院。经胸和食道超声心动图显示高钙化主动脉瓣（AV），平均梯度为76 mmHg，AV面积为0.60 cm ²（在线补充材料，视频S1），中度二尖瓣狭窄，平均梯度为8 mmHg，二尖瓣（ MV）面积为1.42 cm ²（在线补充材料，视频S2），左心室射血分数为79％，无左心室扩张（在线补充材料，视频S3））。冠状动脉造影未发现明显的冠状动脉狭窄。尽管酶替代疗法是MPS-1的有效疗法，但它不能阻止瓣膜疾病的发展。因此，进行了AV和MV置换以及三尖瓣瓣环成形术。确定了增厚的AV小叶和钙化的环。MV环也明显钙化，前小叶增厚和缩短。手术期间从房间隔获得心肌组织，以进行进一步检查。与MV组织中（B和C组）一样，通过光学显微镜在心肌（A组）中观察到泡沫细胞（箭头）。，分别用于CD68的高碘酸Schiff染色和免疫组化）。电镜观察发现，间隙空间中的泡沫细胞（图D，箭头）是巨噬细胞，具有丰富的核异染色质和足突（图E）。泡沫细胞液泡，即溶酶体，含有几种不同的电子密度。此外，在心肌细胞中鉴定出斑马体，变性的溶酶体和MPS的特定特征（F组，箭头）。即使预后比MPS-IH好一些的MPS-IS也会有各种心肌改变。