Papillary fibroelastomas are benign tumors that usually originate from cardiac valves but may have other endocardial origins. We report the cases of 2 patients in whom left atrial appendage masses were initially diagnosed as thrombus. They were treated for embolic stroke and their symptoms resolved; however, their left atrial appendage masses did not regress. After surgery, histologic analysis of the resected masses revealed papillary fibroelastoma in both cases. We discuss the diagnostic and therapeutic dilemmas encountered in patients with papillary fibroelastomas and cardiac masses other than thrombus.

中文翻译：

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左心耳肿块鉴别诊断中的乳头状弹性纤维瘤

乳头状弹性纤维瘤是良性肿瘤，通常起源于心脏瓣膜，但也可能有其他心内膜起源。我们报告了 2 例患者的病例，这些患者的左心耳肿块最初被诊断为血栓。他们接受了栓塞性中风的治疗，症状得到了缓解；然而，他们的左心耳肿块并没有消退。手术后，对切除肿块的组织学分析显示，两种病例均存在乳头状弹性纤维瘤。我们讨论了在患有乳头状弹性纤维瘤和血栓以外的心脏肿块的患者中遇到的诊断和治疗难题。