A Case of Left Atrial Villous-Type Myxoma Mimicking Papillary Fibroelastoma

Takahiro Ishigaki＊	Yasushige Shingu＊	Nobuyasu Kato＊
Satoru Wakasa＊	Tomonori Ooka＊	Hiroki Katoh＊＊
Yoshiro Matsui＊＊＊

（Department of Thoracic and Cardiovascular Surgery＊, and Emergency and Critical Care Center＊＊, Hokkaido University Hospital, Sapporo, Japan, and Department of Cardiovascular Surgery, Hanaoka Seishu Memorial Cardiovascular Clinic＊＊＊, Sapporo, Japan）

A female in her 60 s with a mobile cardiac tumor in the left atrium was referred to our hospital. The tumor was diagnosed as myxoma by echocardiography, CT scan, and MRI. Under cardiac arrest using cardiopulmonary bypass, we resected the tumor through the superior trans-septal approach. We resected two tumors（tumor 1 and 2）with adequate rims of the interatrial septum to avoid recurrence. Although the tumor had a broad base and extended to near the mitral annulus, mitral valve repair was not necessary. Tumor 1 was gelatinous and seemed to be a myxoma;tumor 2 had a lot of papillary structures attached to the solid mass and presented with the figure of a sea anemone when it was put in saline, which is typical for papillary fibroelastomas. The defect of the interatrial septum was closed with the autologous pericardium. The postoperative course was uneventful. Unexpectedly, both tumor 1 and 2 were diagnosed as myxomas on pathological examination. Tumor 2（papillary lesion）included a few tumor cells with positive staining of calretinin typical for myxoma and was diagnosed as a “villous-type myxoma”. Because it is difficult to distinguish myxoma from papillary fibroelastoma by pre- and intraoperative findings, it would be recommended to resect tumors with an adequate margin to prevent recurrence.

 

Jpn. J. Cardiovasc. Surg. 48:405-410（2019）

Keywords：myxoma;papillary fibroelastoma;cardiac tumor