心房細動経過中に発生した冠状動脈塞栓によると考えられる急性心筋梗塞の1例

A case of acute myocardial infarction due to coronary embolism from left atrial thrombus with atrial fibrillation

　症例：55歳，男性。2年前健診にて心房細動を指摘された。昭和61年7月31日入浴後前胸部痛出現し心電図，血液生化学検査，および心臓超音波検査で急性前壁中隔梗塞と診断された。発症2時間後に左前下行枝末梢側の完全閉塞に対してPTCRを施行した。第40病日後の冠状動脈造影は正常冠状動脈所見を呈していたが，左室造影で心尖部にakinesisを認めた。この症例では冠状動脈に動脈硬化性病変を認めず，後日施行した肺動脈造影で左房内血栓が疑われたことから心房細動に伴う左房内壁在血栓に由来する塞栓により急性心筋梗塞が惹起されたものと考えられた。若干の文献的考察を加え報告する。

A 55-year-old man, who has been on follow-up observation with chronic atrial fibrillation, came in with a sudden onset of chest pain on July 31, 1986. He was diagnosed as having acute myocardial infarc-tion indicated by abnormal ECG, elevated serum enzyme and characteristic signs of echocardiography. Emergency coronary angiography was performed 2 hours after the onset of chest pain, and it was reported as showing total obstruction of the distal left anterior descending artery. Pericutaneous tran-sluminal coronary recanalization using 1,200,000 units of urokinase was unsuccessful. The repeated angiograpy performed 40 days later, showed normal coronary arteriogram, but left ventriculogram revea-led akinesis of the apical segment. Furthermore, left atrium opacified in the levophase of pulmonary arteriogram indicated left atrial thrombus.

The cause of the myocardial infarction was consi-dered to be coronary embolism from the left atrial thrombus with atrial fibrillation.

It must be the first report documented by coronary angiography, of coronary thrombo-embolism due to chronic atrial fibrillation without any underlying disease.