左心病変の併存が考えられた右室型拡張型心筋症の1例

A case of right ventricular dilated cardiomyopathy, which involved left ventricle

　16歳女性。検診にて不整脈，心拡大を指摘され，疲労感，洞徐脈が加わり入院。胸部X線で心胸郭比は54.9％と拡大。心電図は左脚ブロック型心室性不整脈，極端な右軸変位，低電位，II，III，aV_F，V_1-4誘導でのT波の平低，陰転化を示した。心エコーでは右室径40mm，左室拡張末期径37mm。三尖弁付着異常なし。心カテーテル検査にて短絡なく，心内圧は正常。心室造影での拡張末期容積係数は右室196.7，左室67.4ml／m²，駆出率は右室20％，左室40％。右室のびまん性拡張と収縮低下のほかに，左室前壁，心尖部にも壁運動低下が存在し，心筋シンチにて左室心筋に不規則な灌流欠損を認めた。心筋生検では右室心筋線維の著明な肥大，部分的な萎縮，消失，配列の乱れ，間質の線維化を認めた。右室型拡張型心筋症と考えられるが，左室心筋病変の併存から，拡張型心筋症との移行が考えられ，心筋症の表現型のスペクトラムを考えるうえで興味ある1例と思われる。

A case of right ventricular dilated cardiomyopathy which also involved the left ventricle was reported. On health screening, a 16-year old woman was po-inted out to have multifocal PVC and cardiomegaly. Subsequently, she was admitted to our hospital be-cause of general fatigue. CTR was enlarged to 54.9 % on chest X-ray. ECG showed LBBB-type PVC, right axis deviation, low voltage and T wave chan-ges. On UCG, RVdD was dilated to 40 mm and LVdD was 37 min. There was no finding of abnor-mality of the tricuspid valve. On cardiac catherer-ization, there was no shunt disease. Intracardiac pressure was normal. The end-diastolic volume in-dex (ml/m²) of RV and LV was 196.7 and 67.4, re-spectively. And ejection fraction (%) was 20 and 40. Ventriculography revealed diffuse dilatation of the right ventricle. And lowered contractility existed not only in the right ventricle but also in the ante-rior and apical segment of the left ventricle. T1201 myocardial perfusion imaging showed irregular per-fusion defect of the left ventricle. Endomyocardial biopsy revealed marked hypertrophy, partial atrophy, disarrangement of myocyte and interstitial fibrosis of the right ventricle. This case was considered to be right ventricular dilated cardiomyopathy. It seemed to be an intermediate form of dilated car-diomyopathy since it also involved the left ventricle. It was an interesting case to illustrate the spectrum of expression of cardiomvopathv.