右心不全症状を契機に診断に至った高齢者の右室二腔症の1例

An Adult Case of Double Chambered Right Ventricle Associated with Right Heart Failure

要旨　患者は60歳，日本在住のフィリピン人女性．主訴は労作時の息切れ．35歳頃より軽度の労作時の息切れを自覚し，心雑音を指摘されるも放置していた．60歳時に下腿の浮腫，軽度の肝機能障害を近医で指摘され当院を紹介受診．超音波検査にて著明な右心負荷所見と右室流出路狭窄を指摘されたため，精査目的に入院となった．入院後心臓カテーテル検査を行ったところ，著明な右室圧の上昇(112mmHg)と右室造影検査で右室内の異常な肉柱発達を認め，右室内が高圧腔と低圧腔に二分される右室二腔症と診断した(肺動脈圧は19mmHgと正常範囲内)．内科的治療は困難と考え，手術により右室内の異常筋束を可及的に切除した．術後経過は良好で，術後に施行した心臓カテーテル検査では右室圧はほぼ正常化していた．

　A 60-year-old woman was admitted to our hospital for dyspnea on effort. She had marked leg edema and liver dysfunction. Cardiac echocardiography showed that she was suffering from of right heart failure. Right heart catheterization revealed an extremely high level of systolic pressure(112mmHg) in the right ventricle. Right ventriculography demonstrated the presence of anomalous muscle bands, which divided her right ventricle into two cavities. Ventricular septal defect(VSD) and other abnormalities were not detected. She was diagnosed as an isolated case of double chambered right ventricle(DCRV). The anomalous muscle bands in the right ventricle were operatively excised in our hospital. After the removal of the anomalous muscle bands, the systolic pressure in the right ventricle became almost normalized to 27mmHg and her clinical symptoms were improved. Many previous reports have shown that most cases of DCRV associated with VSD are diagnosed at a young age. Herein, we present a rare adult case of DCRV without VSD.