関節リウマチにて通院中，多発性脳塞栓を発症した1剖検例

An Autopsied Case of a Woman with Rheumatoid Arthritis Attacked by Multiple Cerebral Emboli

12年来関節リウマチに罹患していた45歳女性が，約2カ月間に計3回の脳塞栓症を発症して死亡した。頻回の脳塞栓症の塞栓源は，生前の精査では特定できなかった。剖検にて，左心室内の大動脈無冠弁基部にリウマチ結節が病理学的に確認され，隆起した結節の表面には容易に剝がれる血栓が付着し，結節には組織学的に少量のフィブリン付着を認めた。また，左内頸動脈末端から中大脳動脈近位部を閉塞していた血栓は，内部に線維化が認められる一方で血管内膜との器質化反応に乏しく，他で形成された血栓が飛来して塞栓したもので，飛来して間もないことが推定された。以上より，本症例では，心臓内のリウマチ結節の部位で形成された血栓が塞栓源となり，脳塞栓症を発症したと考えた。

　心臓内リウマチ結節が心原性脳塞栓症の原因となったという症例報告は極めて稀で，本症例は，その初めての剖検例である。今後，リウマチ患者の脳塞栓症例では，心臓内リウマチ結節も塞栓源の鑑別として考えるべきである。

A 45-year-old woman, who had had rheumatoid arthritis for 12 years, had three attacks of cerebral embolism over two months and died after the final attack. Intensive clinical laboratory investigations did not disclose any specific origins of emboli, but an autopsy revealed a nodule at the base of the aortic valve which was pathologically proved to be a rheumatoid nodule.

　The thrombi were present from the distal part of left internal carotid artery up to the proximal part of the left middle cerebral artery. They were rich in fiber, but poorly organized endothelial cell, raising the possibility that they originated from other parts and have recently reached there. On the top of the rheumatoid nodule, a thrombus was present. It was easily ablated and a small amount of fibrin stuck the nodule. Based on these results, we concluded that cerebral emboli were originally generated at the top of a rheumatoid nodule in the heart.

　In patients with RA, rheumatoid nodules are rarely seen in the heart. If present, they usually cause cardiac failure or atrioventricular block, and seldom result in cerebral infarction. This is the first case in which an autopsy proved rheumatoid nodule in the heart which had caused multiple cerebral emboli. We should consider the possibility of rheumatoid nodules in the heart as an origin of cerebral emboli in patients with rheumatoid arthritis.