森 京子, 平野 玄起, 土居 裕幸, 木澤 隼, 岡本 文雄, 大中 玄彦

Kyoko MORI, Norioki HIRANO, Hiroyuki DOI, Syun KIZAWA, Fumio OKAMOTO, Haruhiko ONAKA

高槻赤十字病院循環器内科

Department of Cardiovascular Medicine, Takatsuki Red Cross Hospital

キーワード : accessory mitral valve tissue, ultrasound diagnosis, pressure gradient in the left ventricular outflow tract

症例は83歳男性．副腎不全でステロイドを内服していた．食欲不振，顔面と下腿の浮腫が増悪し，精査目的に入院した．胸骨左縁第2肋間に収縮期駆出性雑音を聴取し，経胸壁心臓超音波検査を施行した．僧帽弁前尖に付着する約20 mm大の膜状構造物を認め，収縮期に左室流出路に突出する振り子様運動を呈した．さらに経食道心臓超音波検査で詳細に観察したところ，膜様構造物はひも状構造物により僧帽弁前尖に付着する僧帽弁副組織と診断した．また，他の心奇形の合併は認めなかったが，左室流出路狭窄を認めた．無症状で経過し老年期になって初めて診断された僧帽弁副組織を経験したので報告する．

The case was an 83-year-old man who was taking steroids due to adrenal insufficiency. Facial edema and leg edema worsened, and he was admitted for detailed examination. Transthoracic cardiac ultrasound examination revealed a membranous structure of about 20 mm attached to the anterior leaflet of the mitral valve, and showed edematous movement protruding into the left ventricular outflow tract during contraction. Further detailed observation with transesophageal cardiac ultrasound revealed that the membranous structure was accessory mitral valve tissue attached to the anterior leaflet of the mitral valve by a string-like structure. Although no other cardiac malformations were observed, a pressure gradient in the left ventricular outflow tract was observed.