左心耳原発の血管平滑筋腫

Angioleiomyoma Originated from Left Atrial Appendage

血管平滑筋腫（angioleiomyoma）は主に中年女性の下肢に発生する軟部組織腫瘍で，心臓原発の血管平滑筋腫の報告はきわめて限られている1）．われわれは心臓左心耳原発と考えられる海綿型血管平滑筋腫を経験したため，報告する．

A 53-year-old woman underwent cardiac tumor resection. She had been experiencing exertional dyspnea for 3 months due to a slowly growing tumor, which had previously been diagnosed as “benign” and had been followed for 10 years. The operation was performed under median sternotomy with a cardiopulmonary bypass （CPB） stand by for radical resection. The tumor, exposed with two left internal mammary artery （LIMA） sutures, was observed to originate from the left atrial appendage （LAA） without invasion to the surrounding structures. Two staplers were applied to the LAA to excise the tumor without CPB. Pathological examination revealed the tumor was positive for alpha-smooth muscle actin and desmin and contained numerous vascular structures with smooth muscle, leading to a histological diagnosis of angioleiomyoma. Postoperative course was uneventful and the patient was discharged home on postoperative day eight. Dyspnea was alleviated immediately postoperatively and no signs of recurrence were seen after one year follow-up.