狭心痛で発症し胸腔鏡にて確定診断した先天性心膜欠損症の男児例

Congenital Pericardial Defect Presenting as Angina and Diagnosed by Thoracoscopy:Case report

　症例は胸痛を主訴に受診した8歳男児で，入院直後の心電図でST-TやT波の極性などが短時間に変化する所見を認めたが，逸脱酵素の上昇はなく，心不全・不整脈も認めなかった．入院時異常を認めなかった胸部X線像は経過中に左第3弓の突出を呈し，左右側臥位像で中心陰影が大きく偏位したことなどから先天性心膜欠損が疑われた．MRIでは心膜周辺の脂肪層が薄く心膜欠損の確認ができなかったため胸腔鏡を施行して左側心膜全欠損と確定診断した．胸痛を繰り返すこと，心電図変化も認められることから，Marlex Meshパッチにより心臓固定術を施行した．本症例における胸痛の原因は，残存心膜の癒着による張力・癒着部を中心とした左心耳のねじれに加え心膜欠損部辺縁による左回旋枝の圧迫が関与したと推測された．また，本症が疑われる場合に胸腔鏡は確定診断に有用でありうると考えられた．

Congenital pericardial defect is an anomaly, rarelyfound incidentally on thoracotomy or at autopsy. Here,we report a case of congenital complete defect of theleft pericardium, for the diagnosis of which video-assist-ed thoracoscopy was valuable.

An eight-year-old boy was admitted to Toho Univer-sity Hospital with precordial chest pain persisting forseveral hours as his chief complaint. Physical examina-tion revealed nothing of note and the routine laboratorytests, including serum CK-MB and myosin light chain I,were negative for myocardial necrosis. His ECGs record-ed once or twice a day during the subsequent daysdemonstrated variable configurations of QRS complexesand polarity of T waves at each recording. A standardchest X-ray demonstrated a bulge in the left hilarregion, suggesting incarceration of his left appendage.His cardiac silhouette in the left lateral decubitus posi-tion was shown to be significantly displaced leftward.Although magnetic resonance imaging was equivocal,complete left pericardial defect was visually diagnosedwith video-assisted thoracoscopy. Pericardioplasty withMarlex Mesh was performed to minimize the possibilityof myocardial ischemia due to compression of the leftcircumflex coronary artery. The patient's post-opera-tive course was uneventful; oral predonisone of 5mgper day was administered for 4 weeks for preventinginflammatory exudate. The patient has remained free ofsymptoms for the last 2 years.