岡田 大司¹, 吉冨 裕之², 伊藤 早希¹, 安達 和子¹, 石橋 豊³, 岡田 行功⁴, 田邊 一明¹

Taiji OKADA¹, Hiroyuki YOSHITOMI², Saki ITO¹, Tomoko ADACHI¹, Yutaka ISHIBASHI³, Yukikatsu OKADA⁴, Kazuaki TANABE¹

¹島根大学医学部附属病院循環器内科, ²島根大学医学部附属病院生理検査部, ³島根大学医学部附属病院地域医療教育研修センター, ⁴神戸市立医療センター中央市民病院心臓血管外科

¹Department of Cardiology, Shimane University Hospital, ²Department of Physiological Laboratory Division, Shimane University Hospital, ³Department of Rural Medicine Education Center, Shimane University Hospital, ⁴Department of Cardiovascular Surgery, Kobe City Medical Center General Hospital

キーワード : cardiac papillary fibroelastoma, mitral valve, transesophageal echocardiography

症例は50歳，男性．高血圧症にて近医通院中であったが，2004年12月に心機能評価目的で施行された経胸壁心エコー検査にて，径4 mmの僧帽弁腫瘍を指摘された．精査加療を勧められたが，本人が希望せず経過観察となっていた．その後，腫瘍サイズの増大が見られ，本人が手術を希望したため2009年8月に当院入院となった．経胸壁心エコー検査では，僧帽弁後尖（P2）左房側弁腹に10×13 mmの可動性に富む球状腫瘍を認めた．辺縁は比較的整であったが，拡大像では毛羽立ち様であった．茎ははっきりしなかった．また，腫瘍による弁狭窄や閉鎖不全は認めなかった．経食道心エコー検査では腫瘍表面は凸凹し，内部には無エコー部分を認めた．また，3次元（3D）経食道心エコー検査で腫瘍が僧帽弁弁腹に存在し弁閉鎖を阻害していないことを確認した．塞栓症の危険性を考え，腫瘍切除術を施行した．病理組織診断は乳頭状線維弾性腫であった．5年間で腫瘍の増大が確認でき，3D経食道心エコー検査が腫瘍の評価に有用であった僧帽弁乳頭状線維弾性腫の1例について報告する．

A 50-year-old man was referred to this institution in August 2009 for further diagnostic evaluation of a mitral valve tumor. Transthoracic echocardiography performed at the previous hospital in December 2004 revealed a 4 mm mass attached to the mitral valve. Tumor size gradually increased, and transthoracic echocardiographic examination at time of admission to our hospital showed a 10 x 13 mm mobile spherical tumor attached to the posterior mitral leaflet, on the left atrial side of the middle scallop (P2). The margins were relatively regular, but were in a fluffing state in the extended image. The stalk of the tumor was not demonstrated, and no mitral valve regurgitation or valve stenosis was noted. Transesophageal echocardiography (TEE) showed an echolucent area in the tumor, and the tumor surface tumor was uneven. Three-dimensional TEE confirmed that the motion of the mitral valve did not affect the tumor. Because of the risk of thromboembolism, however, the tumor was completely removed surgically. The histological examination supported a definite diagnosis of papillary fibroelastoma. We report this as a case in which increase in tumor size was detected by echocardiography during a follow-up period of 5 years.