開心術時のPTFEシートによる心膜補填後に収縮性心膜炎を来した1剖検例

An Autopsy Case of Constrictive Pericarditis after Pericardial Repair with Polytetrafluoroethylene Sheets in Open Heart Surgery

要旨　患者は65歳，女性．連合弁膜症に対して他院にて1978年に僧帽弁交連切開術および大動脈弁形成術を，1996年には僧帽弁交連切開術，大動脈弁人工弁置換術および三尖弁弁輪縫縮術を施行．2003年より大量の腹水貯留を伴う右心不全増悪にて当科での入退院を繰り返した．2004年6月に右室内圧曲線にて拡張期dip and plateauパターンと胸部CTでの心膜肥厚像を認め，収縮性心膜炎と診断した．心膜剝離術は本人拒否のため施行せず，2006年8月に多臓器不全にて死亡した．剖検では心臓前面にpolytetrafluoroethylene(PTFE)シートによる心膜補填を認め，外側面が厚い線維層に被覆されていた．再手術を念頭においたPTFEシートによる心膜補填が結果的に収縮性心膜炎を招来した本症例を通じ，開心術時の心膜補填の是非を考察する．

　A 65-year-old woman had open heart surgeries consisting of valvuloplasty or replacement of mitral, aortic, and tricuspid valves. Several years after these operations, she was hospitalized repeatedly because of exacerbated right-sided heart failure, especially a bulged abdomen derived from marked ascites. Intracardiac pressure study revealed that ‘dip and plateau' pattern during diastole in the right ventricle together with the findings of thickened pericardium in the chest computed tomography, led to the definitive diagnosis of constrictive pericarditis. The patient refused recommended pericardiectomy and soon died from multi-organ failure. Autopsy showed retrosternal pericardial repair work using polytetrafluoroethylene(PTFE) sheets entirely on the frontal surface of the heart. Although the adhesive circumferential mediastinal tissues or pericardium was scarcely observed around the heart, microscopic investigation demonstrated that PTFE sheets were surrounded by markedly thickened layers consisting of fibrotic tissues. Pericardial repair using PTFE sheets in open heart surgery may cause constrictive pericarditis derived from thickened surroundings due to marked fibrosis despite the avoidance of adhesion within the heart.